HomeMy WebLinkAboutWildland Urban Interface 2002
The Ashland Wildland/Urban Interface
The Ashland Wildland/U rban Interface
Wildfire Management Inventory, Analysis, and Opportunities
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The Ashland Wildland/Urban Interface
Small Woodland Services, Inc.
1305 Butte Falls Hwy
Eagle Point, OR 97524
Table of Contents
Title Page
Acknowledgments
I. AbstractlExecutive Summary I
II. The Ashland WildlandlUrban Interface - The Environment and Its Management 2
A. Introduction 2
B. Vegetation Development and Disturbance History 10
c. The Silvicultural Basis for Vegetation Management 21
D. Vegetation and Fuels Management Strategies to Achieve
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Wildfire Management Objectives 33
E. Integrating Other Resource Values while Prioritizing Wildfire
Management Objectives 47
III. The Ashland WildlandlUrban Interface - Inventory and Analysis 56
A. Landscape Unit Inventory and Descriptions 56
B. Landscape Level Analysis of A WUI 98
1. Management Priorities for Pre-Suppression Activities 101
2. Tactical Opportunities for Wildfire Suppression 107
IV.. Conclusion 114
Literature Cited
Appendix: Types of Wildfire Management Activities
Glossary
List of Scientific and Common Names Used in Report
Rare Vascular Plants Likely in the Ashland WildlandlUrban Interface
Exotic, Noxious Plants in A WUI
Rare Animals Likely in the Ashland WildlandlUrban Interface
ODF Wildfires 1992-2001
Wildfire. . . Are You Prepared?
Maps: Landscape Units
Tactical Opportunities
Management Priorities
Soil Types
Vicinity Map
Drainage Basins (Sub-watersheds)
Precipitation
Acknowledgments
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The following people reviewed this report and/or offered key insights:
Dr. James Agee, University of Washington
Dr. Tom Atzet, U. S. Forest Service
Wayne Rolle, U. S. Forest Service (botanical species input)
Bill Rose, U. S. Forest Service (retired)
Carl Skinner, Pacific Southwest Research Station, U. S. Forest Service, Redding, CA
Fred Way, U.S. Forest Service (wildlife input)
Jim Wolf, Oregon Department of Forestry
I. Abstract
The Ashland Wildland/Urban Interface, described by the acronym A WUI in this report, is an area at
considerable risk of destruction from, and contribution to, large scale, high severity, catastrophic
wildfire. The likelihood of significant loss of lives, property, and resource values clearly suggests that
proactive strategies designed to minimize the likelihood, size, intensity, and duration of wildfire are
of critical importance on individual, community, regional, and national scales. This report provides
an inventory of current vegetational conditions/communities within the A WUI, a key determinant of
wildfire behavior. A range of proactive management strategies designed to manipulate vegetation to
more favorable conditions from a wildfire management perspective are described, based on existing
landscape unit categories developed in the inventory. Management effects on other resources are
described. Initial analyses of overall condition of the A WUI is discussed, including descriptions of
individual management priorities to improve potentials for minimizing wildfire effects, as well as
potential tactical opportunities delineated for use in a wildfire event.
II. The Ashland WildlandlUrban Interface
Environment and Its Management
A. Introduction
Forests in the western United States have burned for millennia under a wide range of frequencies,
intensities, durations and scales (Agee, 1993). Fire has been a critical process shaping the density,
structure, and composition of forests throughout the biologically diverse Klamath-Siskiyou region.
The predominant fire regime prior to Euroamerican settling (particularly those at low to mid-
elevations) involved more frequent fires, ofless intensity and duration, and on much smaller scales
than those that occur today (Agee, 1991, 1993; USDA and USDI 1994). The Ashland Wildland
Urban Interface (A WUI) is on the driest and warmest end of the Klamath Siskiyou province, hence
the greater likelihood that frequent, low-intensity fire played a major role in shaping the development
of its forests and wildlands.
However, beginning in the 1850s, fire regimes began to shift as a result of Euroamerican influences
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on the environment. In the last century, and particularly within the last 60 years, exclusion of fire
from forest ecosystems has been attempted, utilizing increasingly advanced techniques of wildfire
suppression. However, the more we have protected the forests from fire, the worse the problem has
become (Agee, 2002). Increasingly, large scale, high intensity fires threaten lives, property, and
resource values in the West every year.
There is no such thing as fire-free forests or wildlands. Perhaps more appropriately, fire can be
expected to occur, and it is only the frequency, intensity, scale, and duration that we can influence
through our actions. Creating a more resilient forest with fire regimes of lower intensities that are
more easily controlled should be an obvious objective. Passive management (i.e., doing nothing) will
not accomplish this objective; active management is necessary (Agee, 2002). This report describes
strategies for implementing planned disturbances (i.e., management activities) that emulate pre-
settlement disturbances and subsequently help return to a more benign fire regime.
Wildfire management priorities are increasingly being focused on wildland-urban interfaces, those
geographic areas in which the urban and/or suburban setting is juxtaposed and transitionally grades
into the wildland environment. By definition, interfaces are gradational and are thus difficult to
delineate precisely. In this report, the Ashland WildlandlUrban Interface (A WUI) is generally the
area that extends from the edge of the urban/suburban residential and/or commercial areas up to the
U.S. Forest Service boundary. The lands addressed in this report do not include U.S. Forest Service
lands, but rather focus strictly on private and municipal (i.e. City of Ashland) lands. For the purposes
of this report, Tolman Creek Road represents the southern boundary ofthe A WUI, while Wrights
Creek comprises the northernmost boundary. This area comprises a total of approximately 2,625
acres. Elevation ranges from 2000 to 3600 feet above sea level.
Although the lower A WUI boundary was in many places difficult to precisely define, three general
categories of interface boundaries exist. Classic interface boundaries occur where high density
subdivisions lie adjacent to unsettled wildlands (e.g. Greenmeadows subdivision, Mountain Park
Estates at the top of Morton Street, etc.). Mixed interface zones exist where less dense settlement
patterns are scattered amidst wildland settings (e.g. upper end of Elkader Street; Timberline Terrace;
homes in Morninglight Estates and along the upper end of Tolman Creek Road, etc.). Occluded
interface zones occur where areas of wildland vegetation have become surrounded by more
urban/suburban development (e.g., the wildlands of Lithia Park, lower Roca Canyon above Southern
Oregon University, riparian vegetation along Hamilton Creek and others, etc.).
The A WUI is an area currently at considerable risk of destruction from the development and/or
encroachment of high-intensity, rapidly spreading, large scale wildfire. This is at least in part the
result of two main factors that have contributed to increased wildfire hazard throughout the West.
First, the aforementioned altered fire regimes and disturbance histories have significantly changed
vegetation structures, conditions and patterns such that a much more wildfire-prone vegetation exists.
In essence, a dramatic increase has occurred in fire hazard, defined as the type, amount, arrangement,
condition, and location of flammable fuels that form a threat of ignition, rate of spread, and resistance
to control. The increased potential for wildfire and associated adverse impacts have become more
likely in wildland-urban interfaces due to the higher inherent values, better access, and subsequent
increases in successful fire suppression.
Perhaps equally important, however, has been a dramatic increase in the second factor that has
occurred throughout the West, and certainly in the A WUI-increased population densities in areas
formerly strictly wildland in nature. In Ashland, numerous homes currently exist in the area that
burned intensely in the 4,000-acre 1959 wildfire (see Picture #1). With each ofthese residences and
the various accesses to reach them, comes an associated increase in fire risk or the chance of ignition
and sustenance of fire that threatens resources, property, and lives. Accidents, carelessness, arson,
and other human-caused ignitions are clearly associated with increasing population density in
wildland environments. Simultaneously, the presence of residences in wildland environments can
significantly reduce the effectiveness of suppression efforts, as efforts to protect homes in a wildfire
event remove suppression resources from actively battling the fire itself.
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The Ashland WildlandlUrban Interface is a particularly critical area from a wildfire management
perspective for several important reasons.
1. A large number of people live within this Ashland wildland/urban interface, and a significant
number oflives could be lost in a major wildfire event, given the potentially explosive nature of fire
in this area. This is a result of a combination of factors, including extreme fire hazard; extreme risk of
ignition within an area of moderate to the steep topography; limited and restricted access that retards
rapid escape in a wildfire event; the highly flammable nature of some of the homes that could
ultimately contribute to wildfire behavior; and the likelihood of at least partial (or worse)
ineffectiveness of suppression efforts in a major wildfire event. These characteristics are similar to
those in the Oakland Hills fire in 1991 when 25 lives were lost.
2. The area is dominated by a significant number of residences, structures, and other values-at-risk.
Many of those values-at-risk would be lost in a significant wildfire event, at considerable loss to
individuals and the community. In fact, many homes have been constructed in areas that lie in the
path of previous wildfire in the A WUI, such as the 750-acre Hillview fire and the 4,000-acre 1959
wildfire in the north end of the A WUI. In the Oakland Hills fire in 1991, over 6000 structures were
partially or totally lost, resulting in slightly less than 2 billion dollars in damage; 790 homes were
consumed in one hour alone.
3. Once wildfire is initiated within the A WUI, its potential for significantly impacting major wildland
resources within the immediate vicinity is also quite likely. Most notable would be impacts on the
adjacent Ashland Creek watershed with its key ecosystem values, including late successional/old
growth forests of regional and national importance; critical habitats for sensitive, threatened, and/or
endangered species; critical area for wildlife habitat connectivity and transfer of genetic resources
between the Cascade and Siskiyou Mountains; and key watershed values associated with a municipal
water supply. Extremely sensitive and erosion-prone soils suggest impacts from a wildfire would be
considerable over the longer term as well. High to extreme wildfire hazard within the Ashland Creek
watershed itself suggests that prevention of wildfire encroachment into its geographical area is of
paramount importance from local, regional, and national perspectives.
There is a growing consensus among resource managers that relying solely on traditional suppression
techniques will not offer long-term solutions to these concerns. Given the immensity of the task of
trying to prepare for the eventuality of a major and potentially catastrophic fire, prioritization of
appropriate pre-suppression activities becomes critically important. Proactive strategies designed to
reduce the likelihood of such an event, as well as limiting its size, intensity, and duration when it
does occur, are important public policy goals.
Numerous wildland fire hazard assessment protocols have been developed in recent years to aid in
determining where to concentrate finite resources in this effort. Most of these analyses focus
inventory efforts on three main factors:
(1) characteristics of structures and development on a site
(2) characteristics of suppression and response in a wildfire event
(3) environmental characteristics of a site.
Characteristics of structures in the A WUI are a critical factor in determining potential losses during a
wildfire event, particularly in wildland-urban interfaces like the A WUI (Cohen, 2000). Structures
always have been, and will continue to be, high priorities for protection, which obviously commits
firefighting resources that might otherwise be used for suppression of the wildfire itself (see Picture
#2). In major wildfire events, structures actually can become fuel and exacerbate wildfire behavior.
Minimizing the effects of wildfire on structures, and/or their ultimate contribution to wildfire
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behavior if consumed, can be accomplished through many commonly described construction
activities and/or modifications, particularly as regards roofs, siding, and/or decks, eaves, overhangs,
etc. Another key factor that minimizes the potential for structural involvement in a wildfire is that of
creation of defensible space around a home, that is reduction and/or redistribution of vegetation
amounts and continuities within a specified distance from a home. Not only does creation of
defensible space reduce wildfire advance towards a structure, but residences are also logical sources
of ignition and vegetation manipulation within their vicinity reduces the rapidity of fire escalation
and subsequently increases the likelihood of successful initial attack. The City of Ashland has
recently been involved in a grant program that has provided financial assistance to landowners for
creation of defensible space around their homes in portions of the A WUI.
Access and resulting response time are also key determinants of the potential to minimize wildfire
initiation and/or scale/intensity. In wildland settings, good access allows rapid initial attack and
ultimate containment before fires explode into larger fires. Response time for aerial attack during
wildland fire suppression activities is also critical; the move of the air tanker base from Medford to
Klamath Falls will reduce the likelihood of successful initial attack and/or wildfire containment in the
A WUI. In more urban or suburban settings on the edge of the A WUI, actual road characteristics
(width, grade, turnarounds, adjacent vegetation, etc.) can extend response time or perhaps even
eliminate access for emergency fire-fighting vehicles. Available fire protection in these settings is
also affected by water source availability-pressurized, non-pressurized, or fixed fire protection (e.g.,
sprinklers incorporated into structure design).
Obviously, the first two aforementioned factors are critical to determining the effectiveness of
wildfire suppression efforts and particularly to minimizing losses of life and/or important property
values-at-risk. It is difficult to argue with expenditures prioritized to improve wildfire management
potentials in these two arenas. This report, however, focuses primarily on inventory and analysis of
environmental characteristics of a site (i.e., fuels/vegetation, slope aspect, topography, etc.) and their
subsequent potential contribution to wildfire behavior. Not only does this third factor affect wildfire
behavior in the more urbanized portions of wildland-urban interfaces, but also increases in
importance further from residential areas and into the more wildland portions of interfaces. The
importance of environmental characteristics of a site, particularly fuels and vegetation, drives almost
all wildland fire hazard assessments and is probably the most important variable affecting potential
wildland fire behavior in the A WUI.
Given the considerable risk of damage to communities and ecosystems from high-intensity, large-
scale wildfire, and the limited and finite resources available for proactive protection and restoration
work from a wildfire management perspective, there is an urgent need regionally for focused,
integrated approaches to vegetation management that can maximize wildfire management benefits
while minimizing unintended adverse effects.
Small Woodland Services, Inc., was asked by the City of Ashland in autumn, 2001, to begin
development of an integrated approach to wildfire management within the Ashland Wildland-Urban
Interface. The process of developing that approach produced four primary outputs in this report:
1) A general description of the A WUI and the underlying theoretical
framework and management-related realities that form the basis for
implementing wildfire management activities while minimizing adverse
impacts.
2. An inventory and mapping of the interface area with subsequent delineation oflandscape units
based on similar site conditions, vegetation types, and wildfire hazards.
3) Description oflandscape units and subsequent general management
prescriptions for each, thereby providing landowners in the A WUI an
introduction to a range of management possibilities for their properties
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4) An assessment and description of landscape level opportunities and
priorities for minimizing the potential for and impacts from high-intensity,
large scale wildfire through a) pre-suppression management activities and,
b) delineation of tactical opportunities in a major wildfire event.
Presentation of this report was challenged by the need to present professionally accurate information
in a way that is accessible to readers and audiences that range from professional resource managers
and environmental advocates, to policy makers within the City of Ashland, to landowners and other
interested parties, many of whom have limited knowledge of forest, resource and wildfire
management issues. While many professionals may question some of the somewhat simplistic
descriptions of many of the issues and recommendations in this report, other lay readers may be
overwhelmed by its highly technical nature.
Too, it must be recognized that this report is being offered with very limited public input and
involvement. Ashland is blessed with a very well educated and active citizemy, including many
residents who are experts within specific disciplines covered in this report. Local residents'
knowledge and expertise about wildfire issues is essential to creating an effective response to the
threat of damage and destruction from wildfire. Residents can help identify the map features that are
relevant in emergency response situations (e.g., location and condition of secondary access roads,
locked gates, water sources, etc.). Interface residents can also assist in identifying and prioritizing
values-at-risk threatened by fire. Ultimately, public acceptance of needed pre-fire management
activities will undoubtedly depend largely on their belief that the process is open, transparent, and to
their benefit, and that the knowledge, expertise, and values that they bring to the table are sincerely
valued. Without effective public involvement and ultimate acceptance of strategies for reducing
negative impacts from wildfire, this report may be practically useless.
As a result, this report is designed to be a work-in-progress rather than a statement of fact. It should
be utilized to facilitate discussion about opportunities and priorities that hopefully will be guided by
additional, more complete information in the future. As this information (social,
biological/ecological, management-related, logistical, etc.) is collected and added to the data base,
analysis outputs will logically change, and have to be updated in order to remain accurate and useful.
The use of Geographic Information Systems (GIS) to spatially categorize and display information
should facilitate easy updating as changes occur. However, 150 years of human impacts on the
landscape cannot be altered overnight. Although significant gaps in our knowledge exist, it is
imperative that we move forward learning from both successes and failures (Brown, 2002). It is with
considerable humility that this report is offered as a step in that process.
B. Vegetation Development and Disturbance History
Management of any vegetation type designed to achieve a particular set of objectives ultimately
depends on an intimate understanding of: (l) how that type typically develops (i.e., the expected
successionary pathway), (2) the reasons for its current set of conditions, and (3) reasonable and
knowledgeable projections for how planned manipulations will produce desired changes in
developing vegetation. This is particularly challenging because: (1) the Klamath Siskiyou province,
in which the A WUI is located, is internationally known for its unusually high level of vegetational
diversity and variability, (2) disturbance histories have been significantly altered since Euroamerican
settling in the mid-1800s, often in highly diverse and complicated ways, and (3) vegetational
communities today are functionally, compositionally, and structurally unique today, making guesses
as to future developmental trajectories difficult and risky. Nonetheless, this is exactly what is asked
of forest and resource land managers, particularly given that in many situations (including this one)
doing nothing is well recognized as a highly undesirable approach, particularly in the A WUI.
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Forest vegetation composition is continually and significantly determined by relatively constant
environmental variables, such as elevation, aspect, annual rainfall, soil characteristics, and numerous
other factors. Variations in these environmental variables alone produce significant differences in site
conditions. In the Klamath Siskiyou region, these environmental variables are generally most critical
in the influences they have upon moisture availability for plants, as moisture is usually the limiting
factor affecting plant survival and growth throughout most of the area, and particularly at lower
elevations in the eastern edge of the region where the A WUI is located. Most of this area is also
within the rain shadow of Mt. Ashland, such that precipitation amounts average only 20-30 inches
annually, compared with close to 60 inches at Mt. Ashland, only 7 miles to the south. In particular,
the lack of precipitation during summer months greatly affects the type, quantity, and diversity of
vegetation that can survive and prosper.
Aspect is an important environmental variable because greater amounts of solar radiation on
southerly aspects during long, dry summer months limits moisture availability much more so than on
northerly aspects (with easterly and westerly slopes intermediate). Obvious changes in vegetation
occur in the A WUI on opposing southerly and northerly aspects. Douglas-fir, Pacific madrone, and
deer brush ceanothus tend to dominate the more northerly aspects, while much more
Precipitation Map
diverse species compositions occupy more southerly aspects, including not only Douglas-fir but also
ponderosa pine, sugar pine, and incense cedar, as well as hardwoods (Pacific madrone, California
black oak, Oregon white oak) and drought-tolerant brush species, most notably whiteleafmanzanita,
and to a lesser extent deerbrush ceanothus.
Variations in soil properties are particularly important determinants of vegetation on any given site.
In the A WUI, soils are derived primarily from granitic parent material of the Tallowbox (on steeper
sites)and Shefflein (on gentler slopes 10-35%) soil series USDA Soil Conservation Service, 1993).
These are relatively deep, and well to excessively well-drained soils of a very coarse nature easily
prone to erosion. Both surface erosion and mass wasting events, most notably debris slides and debris
flows, have frequently occurred in these soil types in the A WUI, even in undisturbed landscapes. The
potential for increasing these erosional events through active management and/or manipulation of
sites and/or vegetation is of major concern. The New Years Day storm of 1997 revealed the potential
for landslide activity and major associated flooding that occurred in the Ashland downtown plaza
area. This concern is, of course, balanced with potential damage associated with severe wildfire,
including increased soil erosion and landslide activity when vegetation is removed by wildfire.
The easterly edge of the A WUI adjacent the Ashland urban/suburban area and along the terraces and
first hillslopes of the Bear Creek Valley grades into soils from more sedimentary/alluvial and
metamorphic parent materials. These less-coarse soil textures, coupled with the gentler topography,
result in far less potential for major erosional events. These soils also encourage a different type of
vegetation, as they tend to be more moisture-limiting due to changes in depth (shallower) and/or
other structural, textural, or chemical properties of soils can additionally reduce moisture availability.
Clays, for instance, have physical and chemical properties that bind water and make it much less
available for most plants, particularly conifers. Other plants, however, have adaptations that allow
them to survive and even thrive in these conditions. Oregon white oak is an example of a tree that can
survive and even thrive in heavy clays and/or very shallow soils. Although it too can thrive in more
productive soils, it cannot compete favorably with other trees that prefer these locations (conifers,
Pacific madrone, etc.).
In essence, each site contains given environmental characteristics (such as just described) that
encourage (or discourage) certain types of vegetation. Existing plant species can potentially
Soil Type Map
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act as indicators for potential site productivity. A collective analysis of all of the species and relative
comparisons in vigor and abundance between species can help determine the potential productivity of
a given site-and whether the condition of existing vegetation is within the range of historic
conditions and/or an ecological range appropriate for the site.
General patterns of vegetation development over time can be fairly predictable for anyone site,
particularly if no disturbance alters the pattern. As vegetation develops, it typically progresses
through a series of successional stages, each of which contains specific and recognizable
characteristics (see Figure #4). Oliver and Larson (1990) describe four general stages of forest
vegetation development that occur following a stand replacing disturbance: stand initiation, stem
exclusion, understory re-initiation, and old growth. The stand initiation stage occurs for several years
while new plant species invade the site. This stage can be extended for a considerable length of time
in the A WUI when various brush species dominate the site, preventing the establishment and growth
of larger emerging conifers and/or hardwoods. In most cases, however, eventually conifers and/or
hardwood seedlings and saplings develop and grow, and the developing vegetation tends to make a
transition towards stands of trees, initiating the stem exclusion stage. In this stage, growing space
becomes fully occupied, site resources fully utilized, and new individuals prevented from becoming
established. The stem exclusion stage continues until the developing trees reach densities where
natural, density-related mortality occurs. This process initiates the understory re-initiation stage
where new individuals begin to grow in the understory as overstory trees die. Eventually, this
developing understory vegetation helps create a more typical old growth stand structure characterized
by multiple age classes, size classes, and complex structures of multi-layered canopies.
This model, although somewhat simplistic, provides a good conceptual framework with which to
understand how forest vegetation tends to develop over time, particularly in the absence of
disturbance. Carried to logical conclusion, it would suggest that prior to settlement of the west by
European peoples, forests were dominated by primarily late-successional forests.
However, extensive research over the last thirty years has suggested a different outcome. Rather, this
march over time through the four stages of stand development is considerably modified by various
natural disturbances, including wind storms; ice storms; droughts and related mortality; insect and
disease outbreaks; landslides; flooding and/or erosion from peak storm events; fire (ignited by either
lightning and/or Native Americans) and perhaps others. Atzet and Wheeler (1982) found that 98
percent of the stands in the Klamath Physiographic Province have been disturbed by one or more
events. These disturbances historically returned developing stands, or portions of them, to earlier
stages of development, and depending on their scale, frequency, magnitude, season, and historical
variability produced a variety of vegetational types and structures across a landscape. Many of these
disturbance events were synergistic-that is, they cumulatively altered vegetation types, producing an
even wider diversity of vegetational conditions on a landscape. In essence, every forest type
developed under the influence of its own particular disturbance history, which of course varied over
time as well.
Prior to European settlement of southern Oregon, the primary disturbance mechanism in the Klamath
Physiographic Province was fire (Atzet and Martin, 1991). These fires, ignited by Native Americans
and/or lightning, ranged in frequency from 5 to 20 years in the interior valley and mixed conifer
zones that dominate the A WUI.
Understanding of these three categories of site condition determinants (environmental site conditions,
vegetation development patterns, natural disturbance history), can help explain the existing condition
of vegetation type on a site if they are analyzed correctly. However, a fourth major determinant may
be the most important of all- that of changes in disturbance history through active management
within the last 150 years.
Typical post-settlement impacts include many that are commonly known-wildfire, mining, logging,
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grazing and livestock utilization, off-road vehicle use, road building, and various other construction
and recreational activities. Perhaps the impact with the greatest influence is the one that until recently
was the least known and understood-that of changes in fire regimes that were initiated with the
settling of the area in the mid-1800s.
Beginning in the 1850's, significant vegetation modification and changes in disturbance history began
to occur as Native American application of fire was eliminated and new forms of disturbance began
to be implemented across the landscape. Forests began to be harvested in earnest to help build the
developing town of Ashland, and the resulting slash from these operations, coupled with the resulting
increase in more flammable early successional vegetation, created a landscape much more likely to
burn at larger scales and higher intensities. In some cases, high-intensity fire was purposely initiated
by ranchers desiring more pastureland or miners hoping to expose more rock strata and make mining
easier-both clear and purposeful objectives.
Two large scale, high-intensity fires burned throughout large portions of the A WUI in 1901 and
1910. These fires further encouraged establishment and growth of vegetation more well-adapted to
this new type of more infrequent but higher intensity disturbance, a pattern that continues today.
The 1901 and 1910 wildfires were part of a regional trend that led to a policy of fire suppression and
subsequent exclusion from forest ecosystems that remained in place for most of the 20th century.
This human-induced change in disturbance history from frequent, low-intensity fire to infrequent,
high-intensity fire altered the ecological functions previously maintained by frequent, low-intensity
fire. These included:
1. Periodically removed dead and downed material as well as ultimately
reducing stand densities primarily through removal of brush, small conifers
and other understory vegetation. Although some smaller seedlings and
saplings always escaped, low-intensity fires that typically burns in a mosaic
fashion and some larger trees were removed, vertical and horizontal
discontinuities in fuel were generally increased by frequent low-to-moderate
intensity fire. The result was a modified vegetation and fuel profile with a
subsequent decreased likelihood, extent, and intensity of wildfire.
2. By maintaining a healthier, less crowded and more vigorous stand AND
by reducing available habitat (downed slash), forests were far less
susceptible to large scale increases in mortality from bark beetles and oth~r
insects that performed important ecological roles at reduced population
levels. Fire, and smoke, also played a critical role as deterrents for
deleterious forest diseases.
3. Frequent light to moderate intensity fire produced considerable variation
in vegetation species, ages, densities, and structures. This maintenance of
high degrees of biodiversity is an important feature of healthy, resilient
forest ecosystems.
4. Frequent, low-intensity fire maintained more open stand conditions that
encouraged development and maintenance oflarger, shade-intolerant
species, most notably Ponderosa pine and the oaks. In the absence of fire,
species composition has significantly changed, with shade tolerant species
favored. In addition, in the absence of frequent fire, stump-sprouting
hardwoods and brush species that typically grow quite slowly when initiated
by seed, have become much more common, further altering species
compositions.
5. Fire played a critical role in nutrient recycling, particularly in drier,
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moisture-
limiting climates where decomposition can be very slow. Frequent, low-intensity fire recycled
nutrients "locked-up" in above ground fuel (both dead and green) and provided a fresh flush of
vigorous growth, including those species critical for wildlife. In the absence of frequent, light fire, a
greater percentage of total site nutrient capital has been shifted above ground, with the potential for
increased nutrient loss given the greater likelihood of stand destruction through infrequent high-
intensity disturbance.
6. Frequent fire is suspected to have maintained a lower level of above-
ground biomass than exists today after a century of fire exclusion. The
increased transpirational demands of this additional vegetation has altered
the amount and seasonality of water available as groundwater or as overland
flow in streams and rivers, with subsequent impacts on the many competing
users of water, including increasingly impacted fisheries and other aquatic
resources.
Unfortunately, it is apparent today that we cannot prevent fire from occurring in the fire-prone forests
of southern Oregon, particularly given ever-increasing fuel levels. It is more appropriate to think
about attempting to manage the size and intensity of fire, rather than the occurrence of fire
Once initiated, however, the pattern of infrequent but intense wildfire (as opposed to frequent fire of
low intensity) is reinforced by the resulting increased amounts of more wildfire prone early
successional vegetation, which often occurs in relatively continuous vegetation and fuel profiles. This
new disturbance regime further encourages those species that contain life history strategies (stump
sprouting, stored seeds in the duff/soil, etc.) allowing them to thrive, and even outcompete other
species, in infrequent, high intensity disturbance regimes-once again encouraging the likelihood of
high intensity, large scale wildfire. Breaking this pattern and restoring more benign fire regimes is
often a primary forest management goal in wildfire-prone environments.
However, these early successional vegetational communities are now common throughout the A WUI.
Very few examples of vegetation types with individual trees greater than 100 years of age (initiated
before the 190 I / 191 0 wildfires) can be found within the A WUI, while mature trees 200 to 400 years
of age are not uncommon in the mid to upper elevations of the adjacent Ashland Creek watershed.
Most of the vegetation in the A WUI is heavily dominated by stands of mixed conifers and hardwoods
initiated within the last 40 to 100 years. More recent disturbance events (such as the wildfires of 1959
and 1973, clearing for homesite development, logging and/or other significant vegetation removals to
achieve forest management goals, etc.) have resulted in vegetation in the earlier stages of succession,
most notably brushfields, grasslands, and the like.
Changes in disturbance history have also resulted in a high proportion of individual trees and stands
under significant stress in the A WUI. These stand conditions provide ideal conditions for rapid
escalation of bark beetle populations, as bark beetles can sense and generally attack trees under
severe cumulative stress. Other factors such as drought, disease, logging damage, soil compaction,
and others add to cumulative stress, making trees that much more susceptible to insects.
Once a bark beetle gains entry to a weakened tree, it can chemically communicate this condition to
others of its species, thereby causing a "mass attack" which kills trees outright. Usually, several
species of beetles work synergistically to overcome individual tree's natural defenses (primarily
excessive pitch production). Flat headed borers (Melanophila drummondi) and Douglas-fir beetles
(Dendroctonus pseudotsuga) have been causing the extensive mortality of Douglas-fir throughout the
A WUI. An entirely different cadre of bark beetles, primarily western pine beetle (Dendroctonus
brevicomis), mountain pine beetle (Dendroctonus ponderosa), and pine engraver beetles (Ips pini)
attack and kill the pines.
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Each beetle has its own particular biology, and knowledge of that biology is critical to the success of
any forest management activity. For example, Douglas-fir beetle tends to concentrate its activities in
Douglas- fir trees 10 to 12 inches diameter and larger. This is particularly unfortunate in the A WUI
because many of the preferred overstory Douglas-fir have been, and are being, killed by bark beetles,
leaving only suppressed, poor quality understory conifers. The opportunity for improving stand
conditions through silvicultural activities is compromised in this situation, as the preferred leave trees
can be killed by bark beetles prior to initiation of stand
density reduction.
Although insect-induced mortality of conifers is an important functional process in healthy forest
ecosystems, its increased occurrence on larger scales has exacerbated the trend towards even more
higher intensity, large scale disturbances, including wildfire. When populations of these cadres of
bark beetles explode, even healthy trees can be overcome and mass mortality can occur. Without a
proactive attempt to reverse this process through silvicultural treatments, this process of tree and
stand mortality will continue, with much greater amounts of mortality possible. Increasing the
amount of dead wood, both standing and on-the-ground, can increase the intensity, rate-of-spread,
duration, and ultimately size of wildfire.
Another major form of disturbance currently in the A WUI is dwarf mistletoe disease, primarily on
Douglas-fir. Dwarfmistletoes are flowering, seed-bearing, perennial plants that attack conifers. They
do not have enough chlorophyll, however, to produce their own food. Thus, they rely totally on host
trees for nutrients and water and continually weaken an infected conifer until it dies or succumbs to a
secondary attack, such as bark beetles. When the host tree dies, the dwarf mistletoe plant dies.
A specific species of dwarfmistletoe is usually confined to a corresponding single species of conifer.
Reproduction is by seed, which is aerially spread from tree to tree. Rate of spread is generally about 1
to 2 feet per year, although the sticky seeds, forcibly shot from the fruits in fall, can fly as much as 30
to 40 feet or more. Since they prefer high levels of sunlight, dwarfmistletoes can spread more rapidly
in open stands than in closed stands. For this reason, partial cutting and/or thinning has been known
to rapidly increase dwarf mistletoe infections if a diligent job of removal is not accomplished (usually
followed by a second entry to remove infected trees missed in the first entry). The most undesirable
element of dwarfmistletoe infection occurs when poor quality, infected overstory trees spread the
disease to young, healthy saplings in the understory, thereby insuring the long-term continuation of
the disease. Dwarfmistletoe disease is a slow, subtle form of disturbance that can significantly change
stand conditions over time.
Root diseases are another slow, subtle form of disturbance that has long-term repercussions for
vegetational development and stand succession. Although they appear to be uncommon in the A WUI
at this time, these subtle, damaging agents are everywhere, are usually much underrated, and are very
difficult to control.
Four major species of root disease are common in southern Oregon- Armillaria, Phellinus
(laminated), Annosus, and Black Stain root disease. Each has its own particular biology and options
for management. Unlike dwarfmistletoe disease, destruction of the above-ground portions of trees
does not necessarily remove root disease from forest ecosystems. Ongoing monitoring and early
protection is critical for preventing excessive destruction from these diseases. Minimizing damage to
residual stems during logging, planting or encouraging resistant species, and particularly maintaining
stands with trees of high vigor are the most important management techniques that can help limit the
spread of most root diseases.
Other forms of disturbance appear to be much less important in terms of influencing vegetation
development in the A WUI currently. Stand level replacements of vegetation via insect, disease, or
fire-related mortality may, however, increase the likelihood of slope stability failures as roots die (see
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Picture #3). Larger slope failures can be significant, though usually somewhat isolated, forms of
disturbance that return sites to the beginning stages of succession.
C. The Silvicultural Basis for Vegetation Management
Humans have been manipulating vegetation to achieve pre-determined objectives (agricultural, forest
resource, cultural, etc.) for thousands of years. In today's complex environment, where social,
economic and ecological values intermix, silviculture is the science and the art of modifying and
manipulating vegetation to achieve both short-term and long-term objectives of forest and resource
landowners.
In sound silviculture, an understanding of how and why vegetation initiates and develops, over time
and place, is necessary if manipulation is going to be successful in achieving desired outcomes. For
the purposes of this report, the primary objective for vegetation management in the A WUI is to
achieve conditions that reduce the likelihood, size, and/or severity of wildfire, while minimizing
negative impacts, or even promoting where possible, other desirable values and resources (e.g., water,
wildlife, aesthetic, etc.). An overview of the effect of various styles of vegetation manipulation on
these other resources is provided elsewhere in this plan. In this section, however, the use of
silvicultural principles for vegetation manipulation to achieve wildfire management objectives is
summarized.
Optimizing wildfire management benefits through active alterations in existing fuels and vegetation
will depend on understanding relationships between two disciplines: silviculture and fire
management (Weatherspoon, 1996). Planned and periodic removals of vegetation can be thought of
as planned disturbance events that imitate natural disturbance events (e.g., fire in the pre-settlement
era) in ways that help achieve desired objectives. In planned disturbance events, the most important
vegetational characteristics to inventory, manipulate, and evaluate over time are structure, density,
and composition. In current untreated conditions, the structures, densities, and compositions of
vegetations in the existing stands in the A WUI are far from optimal in producing the desired
objectives, particularly as regards wildfire management. In fact, stand conditions are currently
conducive to producing outcomes, such as major stand replacements from insect-related
Stand Development and Density
mortality and/or particularly wildfire, that are highly undesirable to the property owners in the
A WUI, as well as to Ashland citizens.
Vegetational structure is the physical arrangement of vegetation in both horizontal and vertical
directions. Obviously, structure can change considerably as stands move through the various stages of
stand development. Understanding these changes, particularly after various types of disturbances, is
essential for portraying outcomes, both beneficial or otherwise, of vegetation management.
Stand structure is particularly important in determining the potential for any stand to initiate and/or
carry a rapidly expanding catastrophic crown fire (Agee, 1996). All silvicultural manipulations of
vegetation (including utilization of prescribed fire) designed to restore more benign fire regimes
focus on altering three critical structure-related values: (1) types, amounts, and arrangements of
surface fuels; (2) type, amounts, and arrangements of crown fuels; and (3) the distance between the
two, or crown base height, as influenced by the development of ladder fuels. Improvements in any of
these three structural values reduces the potential severity of a wildfire and the subsequent impacts
that result, while increasing the likelihood for potential control and ultimately reducing the size of
developing wildfires (Agee, et aI., 2000). From a management perspective, however, reduction in
wildfire behavior is usually most dramatically reduced by first altering surface fuels, secondly
increasing crown base height (i.e., ladder fuel removal) and thirdly altering crown fuels (Van
Wagtendonk, 1996; Agee, 2002).
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Vegetational density is the actual amount of vegetation growing on any given site, often expressed in
terms such as trees per acre. Density follows relatively predictable increases following an initial
disturbance that removes vegetation from a site. As vegetation returns and grows on such a site,
desirable and undesirable outcomes can be predicted for any particular resource management
perspective, such as wildfire management, wildlife habitat, etc.
Almost all of the vegetation in the A WUI currently was initiated following the significant change in
disturbance history that occurred with European settling of the area. In fact, most of the vegetation in
the A WUI appears to have been initiated following moderate to high intensity disturbances, primarily
wildfire, in the 20th century, in which most and in some cases all of the vegetation was removed.
Notable dates for these disturbances include 1901, 1910, 1959, and 1973.
Following major disturbances such as these, the earliest stage of stand development, the stand
initiation stage, occurs. The stand initiation stage is currently comprised of areas in the A WUI such
as grasslands, pastures, abandoned orchards, and sites with minimal amounts of naturally regenerated
conifers, hardwoods, brush, grass, and herbaceous vegetation. In this stage, individual plants,
including trees, are free to grow and fully utilize site resources. In tree dominated stands, overall
gro\V1h is less than optimal during this stage as site resources are not fully utilized by developing
seedlings and saplings. The very low fuel levels and considerable fuel discontinuity, in both
horizontal and vertical directions, make these landscape units (e.g., Landscape Unit A) the most
desirable from a wildfire management perspective. These sites provide important tactical
opportunities for suppression in a wildfire event if they can be maintained in their current
vegetational condition.
Eventually, vegetation continues to grow until competition between individuals begins (see Figure 3;
RD = .25). Individual plant growth begins to decline (even though there is still less than full site
occupancy) and total stand growth remains less than optimal. Within this gradational transition from
stand initiation to stem exclusion stages, when vegetation and fuels become continuous both
horizontally and vertically, are some of the most wildfire prone types in the A WUI-the early
successional brushfields and plantations of Landscape Units C, D, E, and F, as well as portions of
other landscape units.
Eventually, the stem exclusion stage of stand development is entered, where overall stand growth
reaches its highest potential. Relatively closed canopies begin to significantly limit the development
of understory vegetation as a result of shortages in light and moisture. Size differentiation between
trees becomes more obvious as larger, more dominant trees begin to separate in size from smaller,
less vigorous trees (see Picture #21). As stand densities continue to increase in the stem exclusion
stage, a relatively long plateau occurs when stand growth is optimized and full site occupancy exists
(see Figure 3).
If disturbance is forestalled, however, through such practices as fire suppression and exclusion,
increasingly dense, stagnated stands continue to develop, and self-thinning from density-related
mortality begins towards the end of the stem exclusion stage (see Figure 2.C.). Site occupancy can be
more variable, particularly as individual trees or small patches of trees die, often in conjunction with
insect attack exacerbated in these stressed stands. The biology of the cadre of insects that attack
Douglas- fir results in the larger trees in the stands being attacked and killed. This is unfortunate in the
A WUI because this size class is usually preferred from both silvicultural (stand vigor) and wildfire
management perspectives.
In some situations (e.g., Landscape Unit J), however, size differentiation is minimal due to excessive
stand densities, and stand stagnation can result in which individual trees significantly decrease in
growth and vigor, while stand growth remains high. In these stand types, excessive competition
throughout stand development encourages rapid early height growth, elevated crowns of minimal
size, loss of lower limbs due to minimal light during the long period of closed canopies, and
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subsequent minimal development of ladder fuels (see Picture #27; Figure 4.A. - Stem Exclusion)-in
essence, creating favorable fuel discontinuities between surface and crown fuels. Initiating crown
fires in these stand structures is difficult, a favorable occurrence from a wildfire management
perspective. However, in these situations very dense canopies on a stand level can also represent a
continuous, though elevated, horizontal fuel profile that can carry crown fire if it enters and is
sustained in such a stand.
Eventually, with continued stand growth and individual tree decline in these extremely stagnated,
over-dense stands, a relatively predictable boundary is reached that is a theoretical maximum between
tree size and stand density. At this boundary point (see Figure 2), additional stand growth is offset by
a corresponding decrease in numbers of trees as they die. This decrease can occur dramatically,
particularly in stagnated stands where populations of bark beetles can rapidly explode such that even
the healthiest conifers can be attacked and killed. In these situations, patch sizes can become quite
large, such as occurred in the upslope positions in Lithia Park in the early 1990's when virtually all of
the 80:!:: year-old overstory Douglas-fir 10 inches dbh and larger were killed. Insect-related mortality
in patches of expanding sizes ultimately encourages the patch to return to the more fire-prone early
successional vegetational structures, particularly if a stand was dominated by a single species, such as
Douglas-fir. Fuel loading in
Figure #2
these patches can be excessive as the snags fall to the ground, and resulting fire impacts can be severe
in terms of intensity and duration, as well as increasing the likelihood of wildfire spread into the
crowns. This is the process that has occurred in much of Landscape Unit H, and is beginning in many
places in Landscape Unit J (i.e., the beginnings of the understory re-initiation stage of stand
development (see Figure 4A).
It must be noted that openings and/or patchy stand structures are not negatives to be avoided at all
costs, particularly if considering the longer time frames and/or larger frames of reference typical of
watershed level management. Creation of more diverse vegetational structures may be able to be
planned for and initiated once the large bulk of the A WUI forestlands have been upgraded from
silvicultural (improved stand vigor, reduced susceptibility to insects) and wildfire management
(reduced fuel loading on an area-wide basis) perspectives. In fact, prior to the significant alteration of
disturbance regimes initiated beginning with European settling of the area, it is likely that frequent,
low to moderate fire in the A WUI and associated Ashland watershed created constantly changing
patterns of gaps or openings of reduced vegetation and fuels. This pattern, called gap dynamics,
creates a variable mosaic of fuels that can discourage development of stand replacement wildfire.
These more heterogeneous combinations of stand structures and conditions is a desirable future
condition from many perspectives, including wildfire management.
In some stands in the A WUI, most notably in Landscape Unit G on more southerly aspects, initial
tree densities following the major disturbances were low, probably as a result of dense competition
from associated brush species. In many situations, some of the older overstory trees survived the fires
and helped produce a different successional pathway than occurred after stand replacement wildfire
(see Figure 4B). As a result, a more open and variable density of overstory trees occurs in this
landscape unit, particularly as compared to other mid-successional stands such as Landscape Unit J.
Tree recruitment into the understory of more shade tolerant species such as Douglas-fir and incense
cedar corresponds with gradual decline of shade intolerant brush species. Subsequent development of
more ladder fuels and developing multi-layered canopies is undesirable from a wildfire management
perspective, even though overstory canopies are less continuous horizontally than in associated
Landscape Unit J.
Disturbances, either natural (fire, insects and disease, windthrow, landslides, etc.) or planned
(prescribed burning, pre-commercial thinning and release, harvesting, etc.) shift stand densities
backward into lower stand densities (i.e. fewer trees per acre). Successional pathways following
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disturbance in any stand are strongly influenced by the size and intensity of the disturbance (see
Figure 4). Decreasing numbers of trees generally produces associated increases in growth and
diameters of remaining trees, with subsequent increases in tree and stand vigor as well. Creation of
patches or openings by these disturbances (i.e., new stand structures) ultimately can move existing
stands toward the understory re-initiation stage of stand development- that is, ifthey are not first
consumed by higher intensity, large scale disturbance events such as wildfire. These types of stands
have only just begun to develop in the A WUI, while the large percentage remain at extremely high
densities.
Management actions, such as stand density reduction treatments, can be implemented to create stand
structures and densities that can improve individual and/or stand vigor while minimizing the potential
for major density-related mortality in the A WUI, generally a negative from a wildfire management
perspective (see Figure 3). These desired stand densities can be quantitatively measured through the
use of various stand density indices, such as relative density. Relative density compares the density of
trees in any stand relative to the theoretical maximum density for trees of that size. Using relative
density, stands can be managed to create densities that minimize the development of within-stand
insect-related mortality and/or stagnation (relative density is less than 0.65, or 65 percent of the
theoretical maximum). Simultaneously, maintaining appropriate stand densities that fully occupy the
sites (relative density is at least 0.35 or 35 percent of the theoretical maximum) can minimize further
initiation of understory vegetation and ladder fuels and maintain vertical discontinuity of fuels, an
obvious wildfire management benefit (see Figures 1 and 2).
Artificially forestalling disturbance through practices such as excluding fire from forest
Figure #3
ecosystems only increases the likelihood that disturbance will occur, and be of a higher intensity
when it does (i.e., wildfire, major insect-related mortality). Some of the stands in the A WUI are IOn
years of age and have missed 10 or more low intensity disturbance events (fire), thereby being
increasingly set up for a high intensity disturbance, with highly undesirable outcomes.
Implementing planned disturbances (i.e., management activities) can emulate historic disturbance
patterns and help recreate less wildfire prone structures and densities. Implementing stand density
reductions is usually much more effective and less costly, however, if it can be done earlier in the
development of the stand (i.e., before 50 years of age and preferably between ages 15 and 30).
Following initial treatments where more favorable vegetational conditions are created, an ongoing
program of more frequent, multiple conservative interventions throughout the life of a stand can be
more easily accomplished that more closely imitates historical disturbance patterns.
Differences in species composition are not nearly as important as differences in density and structure
in influencing wildfire behavior. Even with significant changes in disturbance history, all of the
major native tree species remain in the A WUI, although alterations in percentage composition by
species have occurred within the last century. The pines, both ponderosa and sugar, are less common
than prior to the Euroamerican settling of southern Oregon, largely due to early preferential harvest of
these species, and the impact of fire suppression and subsequent changes in stand densities, canopy
closures, and other ecological relationships that influence the establishment and growth of pines. If
ponderosa pine natural regeneration is going to be successful, significant stand openings and
reductions in stand densities will have to occur-conditions historically produced by a more frequent,
low-intensity type of disturbance. Changes in disturbance history towards more infrequent, high-
intensity events has likely increased the abundance of those species well adapted to that change,
namely hardwoods and brush species in early successional vegetation and more shade tolerant species
(primarily Douglas-fir and incense cedar) in stand understories. Native grasses and herbaceous
vegetation have likely decreased in abundance in the more dense stands throughout the A WUI, while
exotic, non-native species (e.g., starthistle, hedgehog dogtail, scotch broom, Himalayan blackberry,
and others) have increased, particularly in more open, disturbed sites.
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Specific desirable species compositions should be decided on a site-by-site basis, dependent on
characteristics of the site, the current condition of the stands, and long-term objectives for the site.
Generalized suggestions for desirable species compositions are included in the prescriptions for each
landscape unit.
Figure #4 - Two Basic Successional Patterns
D. Vegetation and Fuels Management Strategies
to Achieve Wildfire Management Objectives
From almost any ecologic, social, or economic viewpoint, a large scale high-intensity wildfire in the
A WUI is undesirable. Reducing the risk of that type of fire in the A WUI is an obvious high priority.
This section describes the various active management strategies that can be implemented to help
achieve this objective.
Fire requires three basic elements to occur--fuel, oxygen, and an ignition source. Obviously,
eliminating oxygen is not a viable alternative and, thus, wildfire management and prevention has
historically focused efforts in two primary arenas-(l) reducing fire risk (i.e., minimizing potential
ignition source), and (2) managing fire hazard (i.e., fuels/vegetation). The A WUI has been classified
as extreme for both fire risk and fire hazard (Ashland Ranger District, 1995), clearly underscoring the
importance of proactive wildfire management in the area.
Fire risk has been defined as the chance of various ignition sources, either lightning or human-caused,
causing a wildland fire that ultimately threatens life, property, or various resource values. Prior to a
fuller understanding of wildfire potentials, much of our efforts were focused on reducing fire risk
(i.e., preventing ignition). Unfortunately, ignition can never be totally prevented. Lightning, arson,
carelessness, and accidents always insure that fire will occur in forested settings. From 1967-1992,53
fires have occurred in the interface area outside of the city limits of Ashland, and 93 percent of these
fires have been started by people (McCormick, 1992). Although reduction of fire risk through
education, regulation, rapid response time, etc., is still important, management and manipulation of
fuels and vegetation (i.e. fire hazard) has increasingly become of more importance and is the primary
focus of this report.
Once initiated, resulting wildfire behavior is determined by three primary elements-topography,
weather, and fuels/vegetation, the "fire behavior triangle." All three legs of the triangle have
significant effects on fire behavior (Agee, 1996).
Obviously, there is little that can be done to alter topography, but knowing that fire likelihood, rate of
spread, and/or intensity increase on more southerly aspects, in uphill directions and in the upper one-
third of slopes, allows wildland fire managers to prioritize wildfire management and fuel reduction
activities. In much of the Klamath-Siskiyou region, topography can playa significant role in the size
and intensity of wildfire due to the steep, highly dissected terrain (Taylor & Skinner, 1998). Utilizing
topographical realities has historically tended to focus most fuel reduction activities on two primary
topographical locations: (1) ridgelines, where wildfire suppression tactics (retardant application,
personnel deployment, backburning, etc.) can offer the greatest benefit, and (2) canyon bottoms,
where temperatures are cooler, humidities higher, and moisture availability greater, creating less
flammable vegetation year-round. Other key topographical features that can affect wildfire behavior
include V -canyons, chimneys, saddles, areas of unusually strong winds, and perhaps others.
Similarly, even though we cannot avoid the wildfire-prone, hotter, drier weather of summer, we can
obviously develop much greater care and concern during fire season. This is particularly important in
the most severe fire weather when fire behavior can overwhelm even very well implemented pre-
suppression wildfire management activities, particularly in steeper topographies. In fact, some
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vegetational communities in the Pacific Northwest that have natural disturbance histories
characterized by infrequent, high-intensity events (high elevation vegetation types, coastal rainforest
types, and portions of the Intermountain West) have fire behavior more strongly controlled by
weather phenomena than by topographical or fuels (vegetation) variables.
However, in low elevation, drier sites such as the A WUI, wildfire behavior is most strongly
influenced by fuels/vegetation. Although knowledge about weather and topography are critical to
successful wildfire management, neither can be proactively altered to improve wildfire management
benefits; the fuels leg of the fire triangle is the only controllable factor ofthe three (Agee, 1996).
Management of fire hazard is the basic premise which guides much of the silvicultural prescriptions
and ultimate vegetation manipulations suggested in this report.
Fire hazard is defined as the kind, volume, condition, arrangement, and location of fuels and
vegetation that creates an increased threat of ignition, rate of spread, and resistance to control of
wildfire. Productive management of fire hazard involves working with three primary conditions of
fuels: types and amounts, arrangement, and continuity.
Greater accumulations of fuels obviously increase both the likelihood and ultimate intensity of
wildfire. Smaller diameter, fine flashy fuels are easy to ignite and encourage rapid rate of spread of
wildfire, while the opposite is true for larger fuels (although larger fuels can greatly contribute to the
ultimate intensity and duration of wildfire).
Arrangement of fuels is important because dense, compacted fuels close to the ground do not pose the
same hazard as do "ladder" fuels that form a constant fuel source from ground into forest canopies.
Snags are also a serious fuel arrangement problem because, once ignited, sparks and fire can be
spread great distances from their tops (i.e., spotting) rapidly increasing fire spread even when the fire
itself may be of low intensity.
Fuel continuity is important because fire spreads rapidly in continuous ground and aerial fuels.
Interrupting the horizontal continuity of fuels (fuelbreaks, roads, grasslands, excessive canopy
spacing, vegetational gaps, etc.) basically removes fuel from the fire in horizontal directions, thereby
preventing or at least slowing its spread. Reducing the vertical continuity of fuels greatly decreases
the likelihood of fire spreading vertically into crowns with its associated increase in spotting, rate of
spread, and fire intensity. Vertical discontinuities in fuels helps maintain fires of lower intensities on-
the-ground, with subsequent reduction in impacts and increased potential for successful suppression.
Removal of ladder fuels, pruning of trees, reduction of surface fuels and minimizing development of
early successional vegetation through appropriate stand management activities are management
methods of maintaining or improving vertical discontinuities in fuels.
Fuel reduction zones are areas where benefits associated with fuel and vegetation modification are
associated with topographical benefits or other key priorities based on location. Various styles of fuel
reduction zones have already been implemented in many places in the A WUI. Fuelbreaks and shaded
fuelbreaks have long been a key element of wildfire management strategies (Green, 1977; Green and
Schimke, 1971; Omi, 1996; Agee et al., 2000). These are areas where vegetation has been reduced
and/or modified such that fires burning into them are more easily controlled. Shaded fuelbreaks retain
a minimum number of healthy overstory trees with flammable understory vegetation largely
removed.
Numerous fuelbreaks/shaded fuelbreaks have been installed in the A WUI around homes, roads, or
other improvements (see Picture #6), as well as in their more strategic locations along ridgetops in
forested wildland settings where they historically have been 150 to 250 feet wide, designed to
effectively suppress encroaching small to medium-sized wildfires. Not only are fuels reduced in these
wildland locations, but fire fighting personnel have easier and safer access and aerial retardant can
effectively reach the ground.
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However, in severe fires, particularly those with excessive spotting, these fuelbreaks have often been
ineffective (Weatherspoon and Skinner, 1996; Van Wagtendonk, 1996). In these situations, larger
zones of modified and reduced fuels have greater effectiveness and use. These "defensible fuel
reduction zones," which often use existing fuelbreaks or shaded fuelbreaks as anchor lines, are much
wider than fuelbreaks, perhaps as much as one-quarter mile wide. These would include treated stands
with reduced amounts, continuities, and/or distributions of fuels that would provide additional zones
of opportunity for controlling wildfire. Ultimately, increasingly large areas of fuel reduction grade
into area-wide or landscape level fuel reduction. This has rarely occurred in the West, although it is a
desirable future condition, particularly for wildfire-prone areas with high inherent values, such as the
A WUI and Ashland Creek Watershed. Ultimate ecological restoration goals can best be achieved
once the area has reached some level of protection from destruction from large-scale, high-intensity
wildfire.
Reducing the likelihood of severe destruction from wildfire depends, then, on an aggressive fuels
reduction and/or modification. Silvicultural thinning and prescribed fire are the most common active
management methods designed to modify fuels and vegetation and subsequently reduce wildfire
danger and restore more benign fire regimes (see Picture #7). Both are legitimate and useful tools
with associated advantages and disadvantages (Brown, 2002), and will likely both have to be utilized
in concert to achieve long-term forest restoration goals (Weatherspoon, 1996). It is likely, however,
that silvicultural thinning, brushing, and other stand density reductions and vegetation modifications
will be much more commonly used than prescribed burning in the A WUI (at least initially) for the
following reasons:
1. Prescribed burning is relatively imprecise and difficult to successfully achieve
ecological and silvicultural objectives, particularly in initial entries when stand
densities and fuel loadings are excessive.
2. The chance for escaped fire in the A WUI carries very serious economic and ecologic
consequences-liabilities that few private owners will be willing to absorb.
3. Very narrow windows of opportunity exist annually when prescribed burning
can be accomplished to meet silvicultural, ecological, and wildfire management
objectives. An extreme level of professionalism, planning, and available skilled
labor is needed in order to conduct a successful burn. Logistical and administrative
realities often thwart implementation of prescribed burning.
4. support as well as the practical application of prescribed fire.
5. Silvicultural thinnings and other appropriate silvicultural practices avoid the previously
described difficulties which are particularly concerning in the A WUI. Silvicultural thinning,
however, can only at best emulate the effects of frequent, low-intensity fire by creating a
structurally less wildfire-prone forest. There are many physical, chemical, biological, and
ecological functions performed by fire that cannot be duplicated by silvicultural thinning
(Agee, 1993; Chang, 1996; Kilgore, 1973). Hopefully, fire hazard can cumulatively be reduced
through silvicultural thinnings and other vegetation manipulations in the A WUI such that
prescribed fire can be more safely re-introduced in the future as an ecological process of fuel
reduction and ecosystem restoration.
6. Silvicultural thinning and other stand density reductions can either increase or decrease fire
intensity and associated severity of impacts (Graham et aI., 1999; Agee, 1996; Weatherspoon,
1996), depending on the type of thinning employed and particularly on quality of slash
treatment. Numerous examples of increased wildfire potential following conventional logging
practices or other stand density reductions have occurred throughout the West, particularly if
resulting slash has been left untreated. However, appropriate silvicultural practices have long
been used to recreate or otherwise alter stands to conditions more favorable from a wildfire
management perspective (Graham, et aI., 1999; Agee, 1996; Weatherspoon, 1996). Stand
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improvement silvicultural thinnings can help achieve wildfire management-related objectives
in the following ways:
I. By thinning and removing a portion of the above-ground fuel, both the
likelihood of crown fire, as well as the intensity and the rate of spread of wildfire
will be significantly reduced, particularly if the resulting slash is also utilized
and/or removed. Thinning can be used to improve fuel discontinuities in both
vertical and/or horizontal directions.
2. By reducing the number of trees competing for a finite amount of nutrients,
light, space, and principally water, a healthier, more vigorous remaining stand will
result, with less likelihood of tree or stand replacement from insects and/or
disease.
3. Growth can be redistributed onto fewer, healthier, more valuable trees, insuring
their long-term survival. Larger trees can be maintained and/or developed much
sooner, with associated elevated canopies, thicker bark, and greater likelihood of
survival of low to moderate intensity fire.
4. Thinning can shift stands to more favorable or desirable species compositions,
in particular encouraging the more shade intolerant species (i.e., the pines) that
have declined in abundance in the last 100 years in the A WUI.
5. Trees infected with dwarfmistletoe or other diseases, or under current attack by bark
beetles, can be removed to lessen the potential for excessive occurrence of these
pathogens. Trees heavily infected with dwarf mistletoe are particularly susceptible to
initiating crown fire, and all snags that ultimately develop are wildfire hazards. Removal
of these trees must be balanced with the important ecological functions they serve in
forest ecosystems.
6. Thinning can make it possible to utilize or market trees that otherwise might be
outcompeted and killed in the natural progression of stand development, an important
consideration for many private landowners. Marketing thinned trees that have
commercial value is certainly appropriate, especially if they are captured as a byproduct
of ecologically sound restoration activities (Brown, 2000; Noss, 2000).
Several different methods of thinning are available, dependent on objectives. The preferential
technique in most situations prioritizing wildfire management in the A WUI is a "low thinning" or
"thinning from below," as it most closely imitates the natural process of stand succession in which
the smaller suppressed trees were outcompeted by larger, healthier trees and/or killed by low-
intensity fire. Thinning from below also selectively removes ladder fuels, creating vertical fuel
discontinuities and stand structures favorable from a wildfire management perspective. This
generalized approach must be tailored to fit individualized stands, however. For example, it may not
be appropriate in stands where the overstory conifers have died or are in rapid decline (and cannot
benefit from the stand density reduction); are heavily diseased (e.g., dwarf mistletoe ); are of
unfavorable species mixes; are adjacent important values-at-risk that require different vegetation
management strategies; and perhaps others.
Leave trees following silvicultural thinnings should be healthy, vigorous, and of good form; free from
damage, disease, or insects; and free to grow after thinning. In addition, leave trees should usually
have at least one-third oftheir total height occupied by a healthy crown (foliage). In the highly
altered stands in the A WUI, leave trees should also usually be the largest trees of any particular age
class, and stand density reduction can be utilized to encourage development of older, larger trees
(Main and Amaranthus, 1996). Having been dominant for the largest time, these larger trees will
release more quickly than other less dominant trees, becoming larger in a shorter time. Larger
conifers are particularly preferred over smaller conifers and hardwoods from a wildfire management
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perspective, largely because their crowns (the flammable portion of the tree) are farther removed
from ground level and surface fires (Agee, 1997). This characteristic allows for greater fuel
discontinuities in vertical directions. Thicker bark and other characteristics also allow these larger
conifers to survive surface fire as well. In fact, frequent low-intensity disturbance (pre-settlement fire
regimes) tends to direct successional processes towards stands dominated by large, mature conifers
(Moir and Dieterick, 1988; Covington and Moore, 1994; Agee, 1993; Morrison and Swanson, 1990).
In stand improvement thinnings in the younger age classes (100 years or less) in the A WUI, larger
trees should only be considered for removal if they are obviously dying, heavily diseased, or insect--
infested, or amidst an overstocking of other more vigorous, larger trees.
The pines, Ponderosa and (rarely) sugar, should generally be the preferred "leave" trees throughout
the management area, particularly on more droughty southerly aspects. Prior to Euro-American
settling of the area and the advent of logging and fire exclusion, native stands contained a greater
percentage of pines, and current species compositions may often be outside the range of historic
conditions. Both pines (particularly ponderosa pine) are shade intolerant, however, and require
reduced stand densities in order to remain vigorous, particularly as understory trees. In many
situations, however, Douglas-fir and incense cedar are preferred over the pines for understory leave
trees, as ponderosa pine in shade is usually tall, spindly, and with poorly developed crowns. Due to
their current scarcity as overstory trees, sugar pine and incense cedar should be elevated in
importance for retention in most silvicultural thinnings. When thinning in the mixed coniferous
forests in the A WUI, however, any of the existing native conifers can be appropriate leave trees, and
overall tree vigor and condition is usually more important than individual tree species.
In most stand improvement silvicultural thinnings in the A WUI, hardwoods should be selected for
removal if they are significantly competing with preferred overstory conifers and/or are slowly dying
as they become overtopped by developing conifers. The increasing number of hardwoods,
particularly Pacific madrone, in the A WUI is largely a stand development response to the change in
disturbance history towards more infrequent, higher intensity disturbances. In this disturbance
regime, stump sprouters have significant advantages over trees that initiate from seed (i.e., conifers).
Pacific madrone initiates quite slowly from seed and, given its thin bark, likely rarely gained
establishment in more frequent fire regimes.
However, intentional retention of hardwoods in silvicultural thinnings throughout the A WUI is
advised, as they perform numerous important ecological functions. The following reasons justify
some retention of hardwoods:
(1) Hardwoods can contribute to improved soil physical, chemical, and biological
properties, and form important mycorrhizal associations with conifers
(Amaranthus et aI., 1990; Amaranthus and Perry, 1989; Fried et aI., 1990).
(2) Hardwoods are important for maintaining diverse wildlife populations and add
to overall vegetational and structural diversity of a stand. Larger hardwoods,
particularly California black oak, are especially valuable for foraging, nesting, and
utilization by numerous wildlife species.
(3) Hardwoods may perform the role of a "nurse crop," ameliorating site
conditions so that natural regeneration of more shade tolerant conifers can occur.
(4) Hardwoods may contribute to reduced wildfire intensity, particularly when
compared to uniform stands of conifers (Perry, 1988; Perry, 1995).
(5) Hardwoods respond to density control measures just as conifers do, and
perhaps with an even greater and more immediate response (Main and Hibbs,
unpublished data).
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(6) In mixed stands, hardwoods may contribute to greater overall gross volume
production than in single species stands, particularly in stands where species
niches are dramatically different and/or symbiosis between species occurs (Oliver
and Larson, 1990). Not only do Douglas-fir and Pacific madrone have different
levels of tolerance to shade (Douglas-fir are more tolerant than Pacific madrone
and often grow under a madrone canopy), but also have important mycorrhizal and
nitrogen fixation symbioses (Amaranthus et aI., 1990; Amaranthus and Perry,
1989).
(7) Future markets may improve for hardwoods. Current prices as high as $1,000
per thousand board feet exist for very high quality hardwoods. Large hardwood
burls have been sold for as high as $10,000 for an individual specimen. Stand
management practices may focus on management of individual high value
hardwoods to maximize economic value.
(8) Stump sprouting hardwoods may have slope stability and hydrologic value in
high intensity disturbance regimes in that they are quickly re-established on site,
minimizing potential losses from soil erosion or slope failures.
Post-treatment stand density is an important goal to identify prior to treatment. In areas of relatively
uniform ages, sizes, and species (e.g., plantations), spacing guidelines can be used to determine
desired stand densities. For example, in these settings a historical guideline known as the D+ rule has
been used in which the average diameter of trees in an area to be thinned is added to in a figure of 4
to 5 to determine the footage spacing between trees.
Perhaps a better way to determine optimal densities, however, is to use basal area as a target rather
than spacing. Spacing guidelines are more appropriate in plantations where species and diameters are
much more uniform. Basal area targets allow one to easily make adjustments in the field when stands
are comprised of multiple diameter sizes, with respective differences in competition. Basal area also
allows one to leave trees in clusters (more typical in naturally developed stands) rather than forcing a
given spacing upon the stand. Ultimately, these stand density guidelines can be used as checks on
what is more commonly an intuitive process of leaving the most vigorous trees in patterns that allow
crowns and root systems to expand and more fully utilize site resources (water, nutrients, light,
space).
Preferred stand density after thinning also depends on the goals and desires of the landowner. If more
rapid development of larger trees and/or more open forests with greater horizontal discontinuity are
desired, heavier thinnings are suggested Lighter thinnings may be preferred to ease a stand out of
severe stagnation, to maintain continuous canopies and retard understory development of ladder
fuels, to reduce windthrow potentials, to grow tighter rings and maintain higher log quality, and/or to
maintain other wildlife or aesthetic values.
Many stands within the A WUI may actually require several entries to reach preferred stand densities
in order to avoid shock, scale, windthrow, or tipping over that occurs with stand density reduction
accomplished too rapidly in stagnated stands. A strategy of multiple, conservative interventions also
allows for ongoing project assessment prior to initiation of significant vegetational changes,
particularly on a landscape level. Spreading out vegetational changes over time and space also tends
to minimize potential negative impacts, particularly in a cumulative or landscape-level perspective.
From a wildfire management perspective, stands with significant infestations of Douglas-fir
dwarfmistletoe are also undesirable. Fuel loadings in these stands are typically higher, and the
arrangement and distribution of fuels in dwarf mistletoe brooms can pose significant problems in a
wildfire event, as they can rapidly convert ground fire to crown fire, as well as acting as torches,
spotting fire far ahead, and rapidly increasing rate of spread of wildfire. Heavily infected trees are
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likely to die within the next five to ten years, further contributing to large snag development, an
obvious disadvantage from a wildfire management perspective.
Management options rely on a careful delineation of dwarf mistletoe infection by location and stage
of infection (dwarf mistletoe rating system), with perhaps a flexible management protocol depending
on the age and vigor of the infected tree, degree of infection, and opportunities to reduce wildfire
potential by removal and/or promote other important values through retention. Several features of
dwarfmistletoes make them ideal candidates for silvicultural management strategies (Johnson and
Hawksworth, 1985): (l) they obligate parasites that require a living host to survive, (2)
dwarfmistletoes are generally confined to a single host species, (3) dwarf mistletoes have long life
cycles and generally slow rates of spread, (4) dispersal of dwarf mistletoe seeds is generally of short
distances, seldom more than 50 feet, (5) dwarfmistletoe infected trees are usually easy to detect.
Untreated dwarfmistletoe in overstory conifers can infect understory trees of the same species,
thereby perpetuating compositions as the infected species is selected out ofthe stand. Isolation
technology in which trees of another species surround the dwarfmistletoe-infected conifers, thereby
preventing its spread, can be used to retain infected trees for their structural diversity and wildlife
habitat values (a number of animals, including northern spotted owls, nest in dwarfmistletoe brooms).
Pruning, an often suggested strategy for controlling dwarf mistletoe infection, is usually not
recommended on a stand-level basis due to the cost of climbing-pruning and because repeated
treatments are usually necessary to remove latent infections (Hawksworth and Wiens, 1996). The
most often utilized strategy for decreasing dwarfmistletoe abundance in a stand is removal of infected
trees. Diligence is required, however, because partial removals in stands can in crease light to
dwarfmistletoe and actually increase its abundance.
As is hopefully obvious from the above discussion, decision-making regarding "leave" versus "take"
trees is a complex one and varies with individual species, combinations of species, densities, sites,
aspects, tree vigor, and a host of other considerations- not the least of which is the objectives of the
owner. Given that these decisions will ultimately determine stand conditions many years into the
future, the professionalism of the people actually implementing thinning decisions becomes very
important in a long-term program of stand improvement.
Slash treatment following (and sometimes included in) implementation of appropriate silvicultural
practices is critical to the successful simultaneous accomplishment of wildfire management
objectives. Many different methods of slash treatment are available. The preferred method from an
ecological perspective whenever possible is prescribed underburning. Reintroduction of fire into fire-
dependent ecosystems like that of the A WUI is likely the single most important management activity
to restore ecosystem integrity, as the dynamic balance between vegetational structure and ecological
functions/processes cannot be accomplished by any other single method. However, it is likely that it
will rarely be used in the A WUI for the reasons previously stated. Implementation of other types of
slash treatment will be necessary.
Removal and utilization of any marketable material (such as logs, post and poles, firewood, etc.) c,m
be effective in achieving fuels reduction while garnering some income to offset expenses.
Unfortunately, the costs of commodity extraction may supersede the potential income in many cases,
particularly when access is poor or non-existent (except by helicopter, a very expensive form of
utilization), as is the case throughout large portions ofthe A WUI. In these cases, fuel reduction and
slash treatment will most likely have to be done on-site by other manual or mechanical treatments.
Piling and burning is the most common form of fuel reduction using fire. Slash is piled, manually or
with equipment such as dozers, and often covered with plastic to facilitate burning in winter when
little risk of fire escape exists. Swamper burning is a form of pile burning where the bulk of the slash
is thrown into actively burning piles. Neither of these techniques truly emulates the low-intensity
surface fires of the pre-settler era, but rather are small spots of intense fire. Although mechanical
piling using dozers is often cheaper than hand piling, it has other associated disadvantages including
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inability to operate on steeper (greater than 30 to 35 percent) slopes, negative impacts on soil
resources, and scarification and germination of stored seeds in the soil that then rapidly return the
next generation of wildfire prone vegetation to the site.
Chipping of slash created by thinning, brushing, or other fuels reduction activities is also possible in
accessible areas where chippers can be easily utilized. Chippers do not typically remove fuels in these
situations (unless they are blown into trucks), but rather redistribute fuels into a dense layer spread
over the forest floor. Chippers are particularly appropriate in areas close to homes and other
improvements where the use of fire is less desirable.
Another form of vegetation modification that incorporates slash treatment is the use of a
"slashbuster"-a large excavator with a cutting head that grinds undesirable vegetation into small
sizes and spreads it out over the forest floor, much as a chipper would do. Set up on tracks, this
machine has much better access than most chippers and can work on gentle to moderate slopes (up to
35 percent). Due to high move-in costs, however, they generally require greater acreage sizes in order
to be practical. Soil disturbance and/or compaction may be an issue on sensitive soils, however, such
as those that occur throughout most of the A WUI.
In low priority fuel management areas, lopping and scattering slash so that it lays closer to ground
level will speed up decomposition and more quickly reduce the drastic fire danger. It must be noted
that lop and scattering following silvicultural thinning, although not as desirable as other treatment
tcchniqucs that remove it from the site, is certainly preferred in most stands to not thinning at all,
even from a wildfire prevention perspective. Wildfire danger is extreme in dense, overstocked,
untreated stands, and even though downed slash from thinning and release activities will represent an
additional hazard for several years, the stand improvement that results over time will encourage a
rapid decrease in the vertical continuity of fuels as trees grow and canopies become further removed
from ground level. Slash should lose its fine fuel component (twigs and needles) within several years
and in slowly compressing to ground level, wildfire potential in the fuelbed will be decreased. Too,
improved vigor of leave trees will avoid wildfire hazards associated with density-related mortality,
snag creation, and associated development of more wildfire-prone early successional vegetation.
Obviously, decisions regarding which method of fuel modification and/or slash treatment to use can
be complicated and depend on a host of factors, including landowner objectives, site conditions,
vegetation type and development trajectories, severity of wildfire hazard, contractor availability, and
others. Ultimately, decisions should be made on a case-by-case basis.
Any plans for considering the use of fire in forest or resource management on private woodlands
must be coordinated with the Oregon Department of Forestry. Not only does this coordination help
prevent potential wildfire ignition, but also limits smoke production and direction to days when it
will least impact populated areas.
E. Integrating Other Resource Values While
Prioritizing Wildfire Management Objectives
Management of landscapes and vegetation to maintain or promote the many other resource values is
often different than that which focuses primarily on wildfire management objectives. Understanding
these differences and then delineating the relative importance of each should be a priority for any
forest landowner or manager. Management practices can then be implemented that consider multiple
objectives, while balancing priorities between these objectives.
In this report, however, it is generally assumed that wildfire management objectives will receive the
highest priority, even to the minimization of other resource values on occasion. This is particularly
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appropriate for the A WUI because high-intensity, large scale wildfire, a distinct possibility in the
A WUI, could very well significantly negatively impact all other important values inherent in forest
and resource lands. Nonetheless, this section describing the other key resource values is certainly not
meant to be exhaustive in nature, but rather to introduce landowners and other interested parties to
key concepts. Additional study, information gathering, and professional assistance is advised for
those who want to promote and/or protect multiple values within the context of implementation of
wildfire management activities.
Wildlife management has historically been geared towards improving conditions for specific, highly
desired animals, such as deer, elk, and other game animals, and more recently threatened or
endangered species such as spotted owls in the Pacific Northwest. In this approach, management of
the needs of a particular individual animal basically focuses on managing the four basic features to
insure the continued existence of healthy populations: food, water, cover, and other habitat items
needed for reproduction success. The specific combination of each ofthese four items for anyone
animal must be available from its particular habitat. Increasing the carrying capacity of any individual
animal's habitat usually begins with increasing the habitat value that is "limiting"-or in other words,
the one in the most critical short supply. Just as with trees, minimizing stress and maximizing energy
reserves in animals is the key to maintaining healthy individuals and populations.
Just as in most forest management techniques designed to improve certain values (timber, water,
wildfire management, etc.), management to maximize wildlife habitat values basically revolves
mmmd maintenance and/or manipulation ofve~etation to achieve specific values. Every species of
wildlife has a specific type of vegetation in which it thrives, as well as other types that it at least
utilizes to some degree. Encouraging vegetation types (i.e. densities, structures, and species
compositions) to fit the needs of desired wildlife species has historically been the primary objective
of wildlife management.
Wildlife management has evolved in recent years, however, to include a much broader scale of
reference than promotion of a single species of wildlife. Not only is it clear that managing for single
species is not only very difficult to accomplish (particularly given that research information on
habitat needs of most animals is lacking), but in so doing habitat needs for other animals may be
ignored, altered, or, worse, depleted. Wildlife management has become increasingly focused on
managing habitat values for the widest possible number of species over larger geographical areas and
longer time frames. The complexity of this task is profound and has been made even more
complicated by the fact that animals (and their interactions with their respective habitats) are difficult
to monitor, largely because (unlike vegetation) most move continuously and often over large
distances. Although the habitat needs of certain individual animals, such as big game ungulates, have
become fairly well understood, the failure to maintain and/or provide for unique types of vegetation
on a landscape level (such as old growth forests) has resulted in a rapid decline of other specific
wildlife species that require or prefer this habitat type (such as spotted owls or other species
dependent on mature forest habitat values).
Wildlife management, then, has developed into managing for habitat values on much larger
landscapes, typically at watershed level scales or greater. It has become clear that the habitat needs
for all animals cannot be met on single parcels, unless they are very large. However, individual
parcels may contain specific and perhaps even rare habitat values that may be crucial for certain
individual species (an isolated pond for western pond turtle habitat; a cave for bats; mature forests
that provide uncommon late-successional wildlife habitat values; etc). In essence, management
actions that may benefit some animals may simultaneously be disadvantages for others, while
initiating developmental processes that may encourage yet another cadre of wildlife species in the
future.
Even given this complexity, there are many generalized wildlife management practices that can be
undertaken on individual parcels. The simplest and most important procedure to encourage wildlife
species and numbers in general is to encourage whenever possible the greatest possible diversity of
vegetation, in terms of age, structure, and species. Wildlife species are generally so dependent upon
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vegetation that increasing diversity of vegetation fosters greater numbers and diversities of wildlife
species. It is for this reason that riparian habitats are so important for wildlife numbers and species
diversity. Not only is water and usually cover available at these locations, but vegetational
productivity and species diversity is often greatest in riparian habitats. Plants grow in these locations
that do not grow elsewhere in the landscape. Often, riparian habitat occurs in narrow ribbons along
seasonal creeks or perennial streams (such as in Landscape Unit K), creating a large amount of "edge
effect" where animals are typically concentrated, utilizing closely located but contrasting vegetation
types. This contrast or edge effect also occurs on edges of clearings, grasslands, or other significant
changes in vegetation.
Oak woodlands, such as found in Landscape Units Band C, are an example of a unique habitat type
of importance for many species of wildlife. They offer roosting, nesting, perching, and foraging
habitat for a number of species. Acorns are a particularly valuable food source for a number of
species including deer, squirrels, and other small mammals, some birds (most notably woodpeckers),
and others. Over 175 wildlife species have been identified that use oak woodland habitat types.
Furthermore, oak woodland habitat types are one of the most rapidly diminishing habitat types in the
Western U.S.-hence its additional importance for retention. Stand improvement thinning can
improve oak woodland habitat values just as with conifers, and thinning and fuel reduction
techniques can improve the likelihood that these unique habitat types will survive intact a wildfire
event.
Dul' to major disturbance events throughout virtually the entire A \VUT within the last 100 years, nc,
late successional forest habitat currently exists. Wildlife species dependent on late successional forest
habitat, many of which are the most threatened on a regional perspective (e.g., northern spotted owl,
red tree vole, etc.), likely do not currently reside in the A WUI, although some sporadic utilization of
portions of it may occur (particularly the upper elevations adjacent U.S. Forest Service lands). Some
of the older, 100+ year old forests in Landscape Units G, H, and J are beginning to develop
characteristics that may soon become more utilizable by old-growth dependent species, if they can be
retained and not consumed in a major wildfire event. Management practices, such as stand density
reduction to maintain, and even improve growth of larger diameter conifers, may encourage and
perhaps even accelerate this developmental process. Implementing management strategies to
encourage vertical structure and multilayered canopies could certainly improve the long-term
potentials for mature forest habitat values within the A WUI. However, creating these structures at
this time would conflict with wildfire management strategies, as multilayered canopies contain
excessive ladder fuels capable of initiating and/or aggravating wildfire behavior. Even in optimal late
successional habitat such as portions of the Ashland watershed, managing suboptimal spotted owl
habitat in strategic locations to maximize opportunities for wildfire management may be appropriate
rather than risking catastrophic losses of late successional habitat to wildfire (Ashland Ranger
District, 1995). Given the topographical location of the A WUI and the fact that it is located in an area
with the greatest combination of fire hazard and fire risk of anywhere in the Ashland watershed
(Ashland Ranger District, 1995), it seems clear that treatments designed to produce less flammable
stand structures in the A WUI is imperative for protection of critical wildlife and late successional
forest values in the adjacent 14,000 acre Ashland watershed. This is particularly important given its
location within the 51 ,OOO-acre Mt. Ashland Late Successional Reserve--one of a series of late
successional reserves (LSR) in a network across the Pacific Northwest. The Mt. Ashland LSR is
particularly important because it is a critical part of a connecting link between the Cascade and
Siskiyou Mountain provinces. The relatively large amount (close to 80 percent) of mid- to late
successional vegetational stages within the Bear Watershed Analysis Area (Ashland Ranger District,
1995) make protection and maintenance of these stand structures and habitat values of critical
importance on a regional scale.
Other wildlife management practices can improve both numbers and diversities of wildlife species.
One of the most critical is the maintenance of snags-dead trees that are still standing. Over forty
different species of birds and six species of mammals in southern Oregon alone rely on snags, at least
partially, to complete their lifecycles. Any larger snags (20 inch DBH and larger) are particularly
important as they offer increasingly rare nesting locations for some of the mammals and larger birds
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that depend on them-and are a critical habitat feature that has rapidly declined during the years of
harvesting old growth. Ideally, ten acres of forestland should have at least two (and preferably mon:~)
larger snags greater than 20 inches DBH and 10 to 20 smaller snags for snag-dependent wildlife
species. Clustering of snags, such as occurred where conifers were killed en masse by bark beetles, is
particularly advantageous as wildlife habitat (particularly as compared with more scattered, isolated,
individual snags).
Maintenance of conifers (particularly Douglas-fir) with dwarf mistletoe brooms is also an important
wildlife habitat objective, as a number of birds and mammals utilize this dense cover for roosting,
nesting, and foraging. Northern spotted owls in particular utilize brooms for nesting. Dwarfmistletoe
brooms offer a unique type of cover and structural diversity in the canopies of forests.
Small piles of retained slash also provide excellent cover and nesting sites for a number of birds and
small mammals, although this also has to be balanced with a corresponding increase in wildfire
danger. Special houses specifically constructed for less common animals (bats, western bluebirds,
woodducks, etc.) can improve nesting or roosting success and subsequently encourage the population
viability of these animals.
If wildlife values are prioritized, trees normally removed in stand improvement activities, such as
dying, diseased, defective, deformed, damaged, or heavily suppressed trees, can be retained for their
inherent wildlife values. In addition, species diversity within stands can be encouraged by leaving a
varidy of species, regardless of economic value, during 1nr'/est or ot]ler stand mzmagemcnt activities.
A variety of stand conditions can be encouraged, including uneven-aged, multi-species individual
stands, as well as a multiplicity of stand types within an area or landscape.
Typically, most owners attempt to incorporate management to promote wildlife habitat values
whenever possible with management to achieve other values, such as wildfire management. Forest
landowners or managers should prioritize finding methods and activities (perhaps with professional
help) that balance these values in a way that meets their personal set of values. It must be noted,
however, that the mere presence of large numbers of people, their associated improvements, and even
their pets has already compromised many important wildlife habitat values in the A WUI.
Another common objective or value prioritized by many landowners is maintenance of biodiversity-
that is, the variety of types of living organisms that reside in any given area. Two measures of
diversity are species diversity (the different species living in an area) and ecosystem diversity (the
different types of habitat that support various living organisms). Maintaining species diversity has
been a primary driver of contentious resource management issues in the recent years. Identification of
known locations of sensitive, rare and/or endangered organisms is the most important first step in this
process. Although no known threatened or endangered species currently are resident in the A WUI, it
is certainly possible that casual utilization ofthe area may occur. Numerous organisms of a sensitive
status may exist, however, and identification and monitoring of these species and locations should be
prioritized. If locations are known, management activities can often be adjusted to protect these
organisms without sacrificing larger objectives.
Generally, however, effective management for total biodiversity most commonly attempts to
maximize ecosystem diversity, as maintenance of a wide variety of habitat and vegetation types
insures the greatest possibility for maintenance of the largest number of viable populations of species.
Maximizing ecosystem diversity, however, requires long-range planning over larger, watershed-level
areas such that specific habitat types can be planned for over time and space. This type of coordinated
planning has rarely been done for a variety of reasons. However, our failure to do so has resulted in
significant gaps in habitat types, such as late successional forests. The decline in numbers of animals
(such as northern spotted owls) are an outgrowth of such failures.
Conversely, the younger vegetation and stand structures that currently dominate the A WUI are less
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common higher in the Ashland watershed, where mid and late successional forests dominate. These
younger successional stages in the A WUI support wildlife species that prefer these habitat conditions.
Within any individual management area, however, improving biodiversity and wildlife habitat values
can be achieved by increasing structural diversity of forestlands through such practices as uneven-
aged management; retaining snags and logs, particularly of larger sizes; or leaving patches of
unthinned or untreated areas during harvest or thinning operations. These practices must be carefully
coordinated with appropriate fuel and wildfire management objectives, however. Large scale, high-
intensity disturbances such as large wildfires tend to homogenize landscapes, rather than promote
biodiversity objectives.
Specific activities can also be undertaken to maintain long-term site productivity. The loss and/or
displacement of nutrients within a forest ecosystem has become of increasing concern. Higher-
intensity wildfires of today are consuming a much greater percentage of total site nutrient capital than
the more frequent but less-intense fires of the pre-settler era-a potentially significant impact on
long-term site productivity. The same result can occur by removing large percentages of above-
ground biomass through whole-tree yarding, chipping and/or removal; and/or intense burning of all
slash after major harvests. Much of the nutrient capital in the above-ground portion of the tree is in
the needles, fine twigs, and small branches, and if these alone are left on site then impacts to long-
term site productivity can be minimized. Of course, retention of these fine fuels for productivity
reasons must be balanced with critical fuel management objectives. Variable retention styles of stand
m:1n:lgement can often he utilized to halance wildfire man1semcnt and nutrient managcl1wnt
objectives (Franklin et al., 1997).
It is also important to leave several large logs per acre on-site after harvest as downed woody debris
to decay in place. Recent research has shown these to be important reservoirs of moisture, nutrients,
microbial activity, and small animal activity~all performing critical roles in maintaining long-term
site productivity. Large logs that have limited market value ("culls") are good logs to be retained on
site during a harvest operation, either as snags or as downed woody debris. Determining appropriate
levels of these features in the eastern Siskiyou Mountains is an important current research need.
Perhaps most important for maintenance oflong-term site productivity is protection of healthy forest
soils. Keeping healthy soils requires efforts to minimize soil compaction, erosion, and disturbance.
These most often occur when ground-based equipment is utilized on-site and standards should be
implemented and enforced to protect soils when equipment is being used. Prescribed burning can also
increase erosion when protective duff layers are removed, exposing decomposed granitic soils in the
A WUI. Fires of higher intensities, such as occur in wildfires, can destroy organic matter that binds
soil particles, thereby once again increasing erosion potential. In fact, most of the serious long-term
impacts to forest soils from fire occur when higher intensity fire produces lethal temperatures for soil
organisms and nutrients and removes dufflayers exposing large areas of surface erosion..
Manipulating vegetation to achieve wildfire management objectives is a basic tenet underlying this
report. However, associated with removal of vegetation is a potential increase
in surface flows and potential decrease in slope stability as roots decompose and root strength
decreases. This ultimately can increase the potential for landslide activation and subsequent potential
for increased downslope and downstream impacts upon values-at-risk. Carefully delineated mapping
of landslide activity and zones of hazard by a qualified professional should be enveloped into the
decision-making process regarding forest and resource management of any failure-prone site within
the A WUI.
From a soils, geological, or slope stability perspective, prevention of and/or minimization of
catastrophic wildfire or other high-intensity disturbance events (i.e., large scale insect-related
mortality) that remove all or almost all vegetation from a site is of the highest priority. This, then,
infers the necessity of vegetation manipulation and/or modification such as previously described.
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Doing no vegetation and fuels work will not only increase the likelihood of catastrophic wildfire, but
in many places in the A WUI will also encourage insect-related patch mortality of trees and
subsequent undesirable impacts on slope stability anyway.
Water resources are another critical value to be considered and integrated in any land management
endeavor in the A WUI. A special section in this report (Landscape Unit K) addresses the importance
of hydrologic values in critical aquatic and riparian habitats. Although it is not within the scope of
this report to discuss water and hydrologic values in depth, it is important to address the potential
impacts roads have on forest ecosystems.
No other human impact (with the possible exception oflarge scale stand replacement wildfire) can
have as significant an influence on hillslope processes, aquatic ecosystems, and ultimately watershed
integrity, as does excessive road construction and/or lack of maintenance of existing roads. Roads
dramatically increase drainage efficiency of watersheds, changing flow regimes such that peak flows
are larger, more frequent, and occur much more rapidly. This happens through two basic processes:
(1) road surfaces, compacted and devoid of vegetation and/or duff and litter, intercept precipitation
and allow little infiltration or evapotranspiration; and (2) roads intercept, redirect, and concentrate
subsurface flow. In effect, roads act as surface flow paths for water, becoming an integrated
component of the stream network. Greatly accelerated sediment delivery to stream systems results,
even without considering the impacts associated with the debris slides and debris torrents that occur
during major storm events.
Upgrading, closing and/or restoring, and/or ongoing maintenance of existing roads should be a high
priority for any owner in the A WUI. Various techniques can be designed and implemented on roads
to disperse water to subsurface pathways and reduce sediment input into the stream network. These
include increasing the density of water bars. drainages, and culverts; relocating these drainage devices
where appropriate; outsloping road surfaces; stabilizing cutbanks with riprap retaining walls and/or
filter fabric; restoring vegetation in fresh fills and/or failures; and numerous other techniques. Roads
are also vectors for spread of exotic plants that often have detrimental impacts in forest ecosystems.
Monitoring for and removal of these plants when they occur in road prisms is an important
management responsibility for landowners.
III. The Ashland \Vildland/Urban Interface - Inventory and Analysis
A. Landscape Unit Inventory and Descriptions
Fuels and vegetation are the primary drivers of wildland fire behavior in the A WUI, and the singular
feature that can be manipulated to achieve wildfire management objectives. Through careful aerial
photo interpretation, coupled with intensive field inventory and analysis, the entire A WUI was
mapped for existing vegetation type; 252 units were individually delineated and mapped within the
A WUI. These were subsequently lumped into 10 principal landscape units based on (1) similarities in
site conditions (aspect, slope gradient, soil type, topographical location, etc.) (2) current composition,
density, structure and successional stage of the vegetation, and (3) potential wildfire hazard. This
very intense vegetation mapping is at a much finer scale than most vegetation classification schemes,
such as Atzets and McCrimmons (1996) guide to forested plant associations in southwestern Oregon.
The ten landscape units delineated in this report would be represented in three or perhaps four of the
above plant associations and would not have provided a level of detail sufficient to meet the
objectives of this report.
Correlating the fine-scale mapping with potential wildfire hazard was another primary objective of
this report. A number of wildland fire hazard rating systems have been developed throughout the
West (Wildland Fire Hazard Assessment, 2000). Most, however, have been developed for use on
much larger scales than for the area designated for this report. In addition, most of these hazard rating
systems would have classified virtually all of the A WUI uniformly under the most extreme category,
much as occurred in the Bear Watershed Analysis (Ashland Ranger District, 1995), where both fire
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hazard and risk were uniformly classified extreme throughout the A WUI. However, simply
categorizing the entire A WUI as extreme would allow little opportunity to set priorities for
management and/or evaluate opportunities. For this reason, each of the 10 landscape units were
further categorized into 4 classes of wildfire hazard and
Table - Landscape Unit Summary Information
potential behavior, described as follows.
1. Extreme (Red) - These landscape units are characterized by a likelihood of very explosive wildfire
behavior, largely due to dense, early successional vegetational profiles on moderate to steeper
topography. Control by direct suppression is unlikely in most locations. Opportunities for improving
wildfire management possibilities are difficult and expensive to achieve. The most extreme wildfire
behavior within this extreme class would likely occur in Landscape Unit D, followed by Landscape
Unit F, Landscape Unit C, and finally Landscape Unit E. Landscape Unit E is borderline between the
extreme and high categories, as this vegetational community on cooler, moister northerly aspects
with shortened fire seasons, and a proportionally high amount of deerbrush ceanothus that generally
burns less intensely in wildfires than other early successional vegetation (Skinner, personal
communication).
2. High (Orange) - These landscape units, mid-successional in nature, are slightly less likely than
thl~s~ landscape units in the extreme class to initiate and/or sustain crowning fires, mostly due to
more inherent structural discontinuities in fuels, particularly vertically as ladder fuels drop out in
typical stand development. However, greater overall fuel loading and relatively continuous canopy
fuels in most situations can result in even more uncontrollable wildfire behavior in these landscape
unit; in the most extreme events. Although generally not as explosive as those in the extreme
calC::c.ary inlllost situations, this category aLa suggests a high likelihood or vcry Jifficult wilJfire
behavior to control by Jirect suppression tactics, particularly when individual units are located on
steeper topography. Fire is more likely to burn at a range of intensities in this category. Landscape
unit ratings for wildfire behavior within this class are (most extreme) Landscape Unit G, followed by
Landscape Unit H and then Landscape Unit 1. Landscape Unit J is significantly lower due to greatly
reduced surface fuels and ladder fuels. Landscape Unit H is similar to Landscape Unit J, except for
m~lj( 'I" mortality of Douglas-fir ovcrstory and subsequent increased potential wildfire behavior.
3. Yellow - Landscape units in this category are less likely to burn with to severe wildfire behavior.,
either due to greater live moisture percent in vegetation through the summer season (Landscape Unit
K, riparian habitats) or generally reduced site productivities and subsequent fuel loadings (Landscape
Unit B, oak woodlands). Both landscape units are also generally located on gentler slopes, a
favorable wildfire management factor. Individual units, although also likely to burn in a wildfire
event (although possibly less severely), contain opportunities for improving wildfire management
possibilities at moderate cost. Considerable variation in vegetation and fuels exists within both
landscape units, with portions of each containing conditions that could encourage extreme wildfire
behavior, albeit in a smaller proportion of the total area.
4. Green - Units in this category have inherent site conditions that offer wildfire management
opportunities at low or minimal cost, largely due to very low or even non-existent fuels, and
generally gentle topographical locations. Examples include pastureland or other grasslands, orchards,
quarries, or other areas where vegetation is significantly reduced.
Throughout the A WUI, individual units were also delineated in which wildfire management
opportunities had been significantly improved through implementation of specific management
activities that reduced fuel hazard and wildfire potential. Approximately one-third ofthe total acres in
the A WUI were classified as implemented fuel reduction zones. In these units, the initial wildfire
hazard rating may have been extreme, high or moderate, but through active fuel reduction or other
vegetation/wildfire management activities, was effectively reduced to a lower category, usually by
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one to two classes (i.e. from extreme to high or moderate). These areas can serve as examples of
treatment styles designed to achieve wildfire management objectives. They also helped form the basis
for the prescriptions delineated in this report.
The accuracy of the spatially explicit mapping of the A WUI was challenged by inherent difficulties
in the process. These included:
1. The complex heterogenous nature of vegetation in the A WUI, which is characteristic of the
Klamath-Siskiyou province, one of the most biologically diverse temperate regions in the world.
2. A complicated history of disturbance, particularly close to the urban setting of Ashland, that
creates a confusing mixture of species compositions, stand structures, and age classes of vegetation.
3. The gradational nature of change between vegetation types, rather than the sharp and distinct unit
boundary lines delineated on the map.
4. Units that did not fit cleanly into the 10 landscape unit categories, containing either a combination
of landscape unit types or perhaps a unique vegetation type that had to be "squeezed" into the most
appropriate landscape unit category.
5. Mapping errors that occurred simply because many ('Teas were not available for ground-trutlling
ii'Olll pubiicly clvailabk access.
6. Mapping errors that obviously occurred in the transport of field inventory data into the usable form
displayed on maps in this report. Obtaining exact unit boundaries through technologies such as GPS
\Wj"(' not only practically impossible (without prior :ll'pr(w~d "feverv priv:ltc l::lI1d()wncr--~m unlikely
pOSSibility), but would have been exceedingly expensive.
Developing generic prescriptions and management treatments (e.g., thin everything less than 6 inches
dbh) tends to homogenize vegetational conditions and does not necessarily consider the inherent
variability in function, pattern, density, composition, and structure of a stand or forest. Thus, it is
impnrt,mt to recognize that the descriptions/prescriptions provided in the following landscape unit
inventory are, by intent, very general in nature and will obviously not apply directly to every
individual unit. These were designed to give individual landowners in the A WUI an introduction to
existing conditions on their properties and potential management possibilities to improve wildfire
management objectives, while minimizing negative effects on other resource values. It is -strongly
suggested, however, that individual landowners not rely solely on this information but rather become
much better informed through additional education and/or use of resource professionals to "fine tune"
appropriate vegetation and wildfire management activities. Numerous examples exist throughout the
A WUI where landowners have completed fuel reduction or other wildfire management activities to
meet their own particular set of objectives. These are excellent locations to visually experience and
learn about the various appropriate management activities-and, in some cases, the longer term
effects.
The scope of this report did not allow a wildfire hazard ranking system to be developed for individual
units delineated in the mapping process. However, it would be possible to more fine tune the wildfire
hazard ranking system such that individual units could be ranked. A number of different wildfire
hazard rating schemes have been developed to meet specific goals, utilizing site specific features for
each site such as fuel model, slope, aspect, vegetation type, presence or absence of ladder fuels,
canopy cover, crown base height, surface fuels assessments, and others. These ratings could then be
combined with developmental features of a site (e.g., structural features of dwellings, dwelling
density, emergency access, defensible space, etc.) To determine a rating for an individual site.
It is important to note that some wildfire management activities completed in the spring of 2002 has
not been entered and delineated on the maps for the project. One of the strengths of the GIS-based
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mapping, however, will be the ease with which changes from a wildfire management perspectives
(i.e., recent fuels reduction completed; fuels and vegetation ingrowth into old projects) can be
spatially incorporated onto the map.
The scope of this report also did not allow utilization of stand level or landscape level fire behavior
models, such as BEHAVE (Burgan and Rothermel, 1984) or F ARSITE (Finney, 1998), although
some of the data collected could be useful if outputs from these models is desired in the future. A
careful analysis of the applicability and usefulness of these models for the A WUI would be
imperative prior to their utilization.
Landscape Unit A, Grasslands or Non-Vegetated - 28 units, 234 acres
Topographical Location- Located on various 0 to 30 percent aspects primarily clustered at low
slope positions close to the urban area of Ashland
Vegetation Description - Landscape Unit A comprises various sites in the Ashland Interface area
that have very limited existing vegetation, largely due to vegetation removal activities in the past.
These areas have been cleared for various reasons, including pasture development, orchard
establishment, wildfire protection, quarry establishment and/or expansion, and perhaps other reasons.
These sites currently remain dominated by various grasses and herbaceous vegetation, usually
growing close to the ground. Both native and non-native species are present. Many areas have
c;cat:..:red ll'ees ,,,:slablished allhe time oC c;..:aring (such as u;l,:kuds) 01' dre slowly being re-~ll\::dL'.!')
native brush (most often whiteleaf manzanita and deerbrush ceanothus) and tree (typically Pacific
Madrone, California black oak, Oregon white oak, ponderosa pine) species. On some sites, if this
reimasion process continues the unit will no longer be typical of this landscape unit but rather move
intn one urthe other landscape units dominated by early successional vegetation.
Current 'Wildfire Conditions - The sites in this landscape unit currently are the most favorable of all
the landscape units in the Ashland interface area from a wildfire management perspective. This is true
for two primary reasons: (I) they are generally located on lower gradient slopes (desired for
agricultural uses such as pastures and orchards) that tend to burn less aggressively than steeper
slopes; and (2) fuel amounts are generally very low and confined to surface layers. Planted trees (e.g.
old 'lrchards) ami invading trees and shrubs arc generally uf a very discuntinuous distribution and
will not contribute significantly to increased wildfire behavior in a wildfire event. Irrigated sites in
Landscape U ni t A (rare) represent the best
possible fuel profile in the A WUI. Even non-irrigated sites in Landscape Unit A offer strategic
locations where crown fires will drop to the ground, offering opportunities for direct attack and
possible prevention of wildfire spread. However non-irrigated sites dominated by dry groundcovers
in summer also offer sites where fire initiation can easily occur and rapidly spread, although the
intensity and duration of the fire is reduced. Wildfire suppression must catch these fires by rapid
initial attack prior to their expansion into more wildfire prone adjacent fuel types. Fortunately, given
their management history, most of these sites have good access, allowing rapid initial attack.
Management Opportunities - The various units in Landscape Unit A offer strategic opportunities
for suppression in a wildfire event. Maintenance of reduced vegetational profiles and/or a favorable
distribution of fuels is a highly desirable objective from a wildfire management perspective.
Accomplishing this task requires, in the least, an annual mowing of grasses to reduce fire flame
length and rate-of-spread and ongoing removal of invading trees and/or brush species as needed. If
owners desire to return these areas to more typical native forest types, conifers and/or hardwoods can
be planted and/or encouraged, preferably at wide spacings to maintain fuel discontinuity for as long
as possible. Maintaining summer season irrigation on these sites, where possible, could be a valuable
community objective.
Management Issues - Minimal. Relatively easy landscape unit to manage- basic maintenance can be
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accomplished with equipment or unskilled laborers. Values limited primarily to non-forest users-
pasture, hay, fruit, aesthetics, open space.
Other Resource Issues - Minimal. Erosion and sediment production from quarries. Grassland habitat
for wildlife is uncommon in the A WUI and may be utilized for forage values by a number of wildlife
speCIes.
Landscape Unit B - 31 units, 141 acres
Topographical Location- Low slope positions on valley edges, typically 15 to 45 percent of various
aspects.
Vegetation Description - Landscape Unit B is of uncommon occurrence in the Ashland interface
area, but is separately delineated because it represents a unique vegetation and management type.
Vegetation on the unit is dominated by relatively uniform stands of scrub 3 to 10-inch dbh Oregon
white oak to 30 feet tall. An average of 300 to 750 white oak stems per acre typically occur and often
represent virtually the only tree species. Occasionally, near transitions with more productive sites,
ponderosa pine and/or California black oak may occur scattered in this landscape unit. Understory
vegetation is often dominated by various grasses (native and/or non-native) and herbaceous
vegetation (see Picture #13). A second understory type also occurs in which brush species occur
intcrmixed with the oaks. primarily whiteleaf manzanita. wcdgeleaf ceanothus, and most notably
, , " . '" f'.. . I' " " ,.. ' . '''' (.,. P:." ',' 1') Tl '." 11,." ;, -', "t1"" '. ".' " ;. :, 1; ," , r ; '" .' "I . ,. 1,
,_-I. ,-, ;1....>.-(. ilHj".L.......IL IJ.'Lll.\.'.::-ll..l) \,)l.:..... .1 ,l..u.l! '- 1-T. .h... .....''-..,..Ll....-li....Jli -.)1 Il'-.~,L SlJ......LIL..) ~...J U1\....II....-...il. \...... l): 1...1..
droughty sites where moisture availability is limited due to either (1) the very shallow nature of the
soils, or (2) the high percentage of clay soil particles that make water difficult to extract for many
plants, especially conifers.
CUITcnt \Vildtil'c Conditions - Landscap-.: Unit B is a generally favorabk vegetation type from a
wildfire management perspective. Total fuel levels are low, as these sites of low productivity simply
cannot support a large amount of biomass. However, the presence or absence of brush species and
other ladder fuels as described above alters the wildfire potential of any site in Landscape Unit B.
Sites lacking laddcr fucls are particularly favorable from a wildfire management perspectivc,
although the distance between surface fuels and crown fuels is not large
in these small oaks. The overstory canopy, however, can be fairly dense and continuous, and certainly
capable of sustaining crown fire in a major wildfire, although probably not of the intensity or rate-of-
spread of vegetation types that support greater amounts of uniformly distributed fuels. Individual
units within Landscape Unit B that support a much more continuous understory component of brush
species (i.e. ladder fuels) have high to extreme wildfire hazards, more typical of other early
successional landscape units.
Management Opportunities - Units in Landscape Unit B likely supported the open oak savannah
vegetation type in the pre-settlement era. This type was characterized by later Oregon white oak and
occasional other species (ponderosa pine, California black oak) scattered at wide spacings over a
native grass understory maintained by repeated prescribed burning by Native American peoples.
Return to that vegetation type through active manipulation and understory clearing activities would
be highly desirable from a wildfire management perspective. This can be done by machine and
manual methods throughout most of this landscape unit due to gentle topography. Removal of
excessive understory brush species should be the highest priority where they occur. A follow-up
seeding with native grasses may inhibit re-establishment of more flammable brush species. Livestock
grazing may also help retard development of understory fuels. Sites without excessive understory
development of ladder fuels may only need to be maintained over time, although thinning to reduce
canopy densities in these oak woodlands may also decrease the potential for sustaining crown fires.
Creating and maintaining horizontal discontinuities in fuels and vegetation is usually much more
effective in this landscape unit than attempting to create vertical discontinuity because low site
productivity generally precludes: (1) rapid vertical growth of tree and elevation of canopies, and (2)
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development of continuous canopies that shade out understory species, particularly if the tree species
is shade intolerant, such as Oregon white oak. Any thinning or brushing slash created in these
activities can be utilized if possible; otherwise, it should be eliminated through piling and burning,
chipping, etc.
Management Issues- Landscape Unit B is one of the easiest types in which to conduct management
activities. Reduced slope gradients make access and equipment limitations minimal. Products of
management have limited marketability, primarily firewood.
Other Resource Issues - Landscape Unit B represents an important wildlife habitat type that is
rapidly declining in abundance in the western United States and should be managed to maintain those
values wherever possible. Its close proximity to urban and suburban areas in the A WUI and generally
gentle to moderate topography will make it highly susceptible to development in years to come. Due
to the generally gentle slopes low in the topography of the A WUI, slope stability concerns are
probably minimal in Landscape Unit B.
Landscape Unit C - Ponderosa Pine/Oak - 21 units, 114 acres
Topographical Location- On various aspects, usually in the lower third of concave slopes on
moderate slopes (primarily 25 to 40 percent) immediately above the lowest slope positions
ch:1r:\ctcr;7cd by L:mdscJ.pe Units i\ J.nd B
Vegetation Description - Units in Landscape Unit C are located low in the topography of the A WUI,
often adjacent to the more urbanized settings of the City of Ashland. Shallower and perhaps more
clayey soils reduce productivity for conifer establishment and gro\v1h (particularly as compared to
more productive Landscape Units G, H, and J upslope), although Landscape Unit C is slightly more
productive than Landscape Unit 13, which is typically dominated by extremely drought tolerant
species such as Oregon white oak, wedgeleaf ceanothus, and birchleaf mountain mahogany.
Landscape Unit C includes these species as minor parts of its vegetational mix, but is generally
dominatcd by two other species indicative of slightly more productive sites-California black oak
arid ponderosa pine. Thc pincs arc prcsent often as scattered ovcrstory trccs up to 20+ inches DBIT, :1S
well as younger, smaller trees primarily in openings. California black oak also forms a considcrable
part of thc overstory and mid-story canopics, as well as being a prevalent understory spccies. Othcr
vegetation includes whiteleaf manzanita and occasionally other conifers (often of poor vigor) such as
Douglas-fir and incense cedar. Healthy Pacific madrone and Douglas-fir, site indicators of more
productive soils such as found in Landscape Units G, H, and J, are much less common in Landscape
Unit C. Structurally, the stands in Landscape Unit C are usually multi-storied, with minimal
discontinuity vertically. The overstory pines are often not significantly above the oaks and other mid-
story species. Overstory conifers can be under significant stress in this landscape unit from the
abundance of hardwoods and brush in the understory, and bark beetle related mortality of pines is to
be expected in years to come if no stand density reduction occurs.
Current Wildfire Conditions - Total fuel amounts in Landscape Unit C are intermediate between
more productive sites (such as Landscape Units G, H and J) and the less productive sites (Landscape
Unit B). However, in most places, Landscape Unit C supports a relatively continuous vegetation
profile in both horizontal and vertical directions. Ladder fuels in the form of whiteleaf manzanita and
various sizes of oaks form continuous vertical fuel profiles up into the scattered ponderosa pine
overstory. In many places, older decadent and dying hardwood and brush species can create a volatile
fuel profile. This is particularly important because this landscape unit is usually located on
topographically low slope positions close to dwellings and more urban settings. It is particularly
prevalent in the Ashland Creek canyon and in the Wrights Creek area to the north. Generally gentle,
slopes of this landscape unit can reduce potential wildfire behavior and enhance opportunities for
suppression in a wildfire event.
Management Opportunities - Management opportunities in Landscape Unit C are similar to thoSt:
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in Landscape Unit B. Landscape Unit C likely supported the typical valley pine/oak vegetation type
in the pre-settlement era. This type was characterized by large ponderosa pine (more than in
Landscape Unit B) and oaks (both Oregon white and California black) scattered at wide spacings.
Understory vegetation was probably dominated largely by native grasses. This pre-settlement
vegetation type, highly desirable from a wildfire management perspective today, was likely
maintained by repeated low-intensity fire ignited by Native American peoples. In the absence of this
disturbance mechanism, these landscape units have been encroached upon by numerous oak and
brush seedlings, effectively removing the more open grasslands common to earlier eras. Return to
that vegetation type through active manipulation and understory clearing activities would be highly
desirable to improve wildfire management possibilities. This can be done by machine and/or manual
methods throughout most of this landscape unit due to generally gentle to moderate topography.
Good examples of this type of treatment and non-treatment currently exist in the upper end of the
Wrights Creek watershed. The 1959 wildfire, started near Jackson Hot Springs, burned intensely
through this vegetation type, in areas that now support a large number of homes constructed since
that fire. Growth of vegetation since that event has once again created a fuel profile that could bum
intensely and rapidly in a wildfire event. Creating and maintaining horizontal discontinuities in fuels
and vegetation is much more effective in this landscape unit than attempting to create vertical
discontinuity, just as in Landscape Unit B. Following clearing of brush and other ladder fuels,
ponderosa pine seedlings can be planted to increase their abundance on these sites, although they
should be planted at wide spacings of 15 to 20 feet.
j'vl:1!lagement Issues - Understory fuel reducti(1J1 in this Inndscape unit may be able to be
accompJislled relatively easily inmost places due to the genLle topography and smaller size classes ul
vegetation to be removed. Products from this work would be minimal, primarily firewood and other
small diameter products. Gentle topography, stable slopes, and generally good access close to town
suggest that equipment (crawlers, chippers, slashbuster, etc.) may be able to be used in this landscape
un i t.
Other Resource Issues - Gentle to moderate topography in Landscape Unit C make slope stability
issues less problematic except where slope gradients rise above 50-55 percent. Soil resource values
should be protected by limiting equipment utilization to slopes less than 25-30 percent. Wildlife
habitat and biodiversity values can be very important in this landscape unit, primarily due to the
scarcity of this vegetation type on a regional basis. These areas are remnants of the once more
pre\alent valley pine habitat type, likely maintained and promoted be frequent burning native
peoples. Maintaining and promoting this vegetation type today would suggest extensive
thinning/brushing/burning to create much more open stands dominated by large scattered ponderosa
pine and oaks with an associated native grass understory. The oaks, and particularly California black
oak in this case, are particularly valuable trees from a wildlife habitat perspective.
Landscape Unit D - WhiteleafManzanita Dominated Brushfields - 33 units, 374 acres
Topographical Location- Landscape Unit D is located throughout A WUI on drier, more southerly
15 to 45 percent (occasionally steeper) aspects and other moisture-limiting sites, most notably
ridge line locations
Vegetation Description - Landscape Unit D is a very common type located throughout the A WUI
area. It is located primarily on drier southerly aspects and is characterized by vegetation indicative of
a major, high-intensity site disturbance generally within the last 10-50 years, such as the 1959
wildfire in the northern part of the A WUI, and the 1973 Hillview fire. Vegetation in Landscape Unit
D is dominated by dense brushfields of whiteleaf manzanita, with interspersed clumps of stump
sprouting Pacific madrone. Both species are well adapted to recover, if not thrive, following intense
disturbance-whiteleaf manzanita through rapid germination of scarified (by the disturbance) seed
stored in the duff, and Pacific madrone through rapid stump sprouting. These two species tend to
totally dominate most sites in Landscape Unit D, although scattered ponderosa pine, California black
oak, and deerbrush ceanothus may also occur, particularly around the transitional edges. Brushfields
are usually dense and continuous, fully occupying the site and generally preventing establishment
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and/or growth of other vegetation even for as long as 50 years or more. Many of these sites are
capable of, and historically probably did support, mixed stands of conifers (particularly ponderosa
pine) and hardwoods, more similar to that currently found in Landscape Unit G.
Current Wildfire Conditions - Landscape Unit D is perhaps the most flammable and wildfire prone
of the vegetation types in the A WUI. The vegetation is dense, uniform, and highly flammable,
particularly during dry summer months, although this vegetation type can also bum during dry mid-
winter times. The location of Landscape Unit D primarily on hot, dry, southerly aspects insures that it
will support the longest burnable fire season. Units on steeper slopes of 40-50 percent or greater, are
particularly prone to extreme wildfire behavior due to excessive convective fuels preheating. This
allows for little chance for direct attack or immediate control in a wildfire, except perhaps on
ridgelines.
Management Opportunities - Changing the vegetational profile to a less wildfire prone condition
should be a priority throughout Landscape Unit D. Basically, this will involve removal of the
vegetation through manual or mechanical means. Manual hand removal of vegetation has the
advantages of not scarifying stored seed (i.e., whiteleaf manzanita) and subsequently minimizing re-
establishment of this wildfire prone species. Hand removal, followed by piling and burning, can also
be done on steeper slopes where mechanical removal is not desired, particularly on decomposed
granitic soils. Mechanical removal, such as utilizing crawlers, slashbusters, or other
chipping/grinding machinery can be done on gentler slopes more cheaply if enough acres are
~1\ :l'lhl' !\) \\'~1!T~1!1t 1~1(~\'c-in c()st.~ (\~-"ll !~.; l,-':~l'i,-":l~;i\'!_' ;--"':i_'l':!l;"'Y. \n ili~ln:,' situ:ltl(,ns~ C\'i"ll r"\:1:'11~-11
reilllvai in strips or patches can produce wildfire managemel1l benefits while avoiding the massive
removals that can conflict with other values. Vegetation removal is particularly effective in specific
topographic locations, favorable from a wildfire management perspective, most notably ridgelines
and perhaps along roads where access for firefighting equipment and personnel is available.
Regardless, the wildfire management benefits will be short-lived (10 years or less), as vegetation
becomes re-established on site. Reforestation can often follow initial clearing (site preparation, in
reforestation vernacular), as a short window of opportunity exists where planted conifer seedlings can
compete favorably with other invading vegetation. Control of invading vegetation in a 3 to 4-foot
radius around each seedling may be necessary in order to insure survival and/or improve growth
during the first several years following planting. Ideally, conifer establishment followed by active
management during the next phase of stand development (~;ee Landscape Unit F) can, in the long
term, produce a less wildfire prone vegetation type that can remain on site and perhaps retard
development of the more wildfire prone, early seral brush and hardwood species that would otherwise
develop and dominate. Ongoing maintenance to restrict wildfire-prone vegetation development
(brushing, thinning, etc.) is necessary in order for units to remain as functional fuel reduction zones..
Management Issues - Completing fuels management in this vegetation type is generally a fairly
simple process, although the work itself can be very taxing physically and/or very expensive if
undertaken by manual methods. Using equipment on gentler slopes can reduce up-front costs,
sometimes significantly, although soil disturbance and erosion impacts can increase dramatically on
moderate to steep slopes in these decomposed granitic soils. Re-invading vegetation can also be
difficult and expensive to control, especially when germination is encouraged by equipment
utilization. Marketable products are minimal from vegetation removal from these sites.
Other Resource Issues - Extensive removals of vegetative cover to achieve other objectives
(particularly wildfire management objectives) can potentially aggravate slope instability, particularly
on slopes greater than 50 percent. Vegetation removal in patches or contour strips can help minimize
this potential. Vegetation removal in this landscape unit can also improve wildlife access, as well as
increase potential plant species diversity- two important factors in wildlife management. These types
of removals also can encourage invasion and spread of exotics, however- an unfortunate outcome of
complete vegetation removal on any site in the A WUI. Careful monitoring and removal of invading
exotics should be an important priority in fuels reduction projects in Landscape Unit D. Establishing
native grasses immediately after brush removal may be a way to discourage re-establishment of brush
and invading exotics (see Picture #18).
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Landscape Unit E - Douglas-fir/Pacific Madrone/Deerbrush Ceanothus
25 to 50 Years - 20 units, 324 acres
Topographical Location- Landscape Unit E is located on mostly steep (primarily 40 to 65 percent,
although ranging as high as 80+ percent) primarily northwesterly to northeasterly aspects in the upper
half of concave slopes in the A WUI.
Vegetation Description - Landscape Unit E comprises sites primarily in the upper elevations of the
interface area located on moderate to very steep northerly aspects. This landscape unit is
characterized by early seral native vegetation initiated after major high-intensity wildfire events -
most notably the 1959 wildfire in the northern portion ofthe A WUI (see Picture #19), and the 1973
Hillview fire in the southern portion of the A WUI. In these wildfire events, most, if not all of the
above-ground vegetation in Landscape Unit E was removed by wildfire. Existing vegetation ( 40+
years of age and younger) is dominated by those species most well-adapted to thrive after this type
of disturbance. Pacific madrone and deerbrush ceanothus. Both species are stump sprouters that
quickly become re-established after wildfire, gaining rapid domination of the site and discouraging
subsequent development of other invading species. In some situations, naturally regenerated Douglas-
fir were able to gain establishment at the same time (usually because a nearby overstory seed source
escaped the wildfire) and have been able to gain a place in the overstory, now as 2 to 12 inch DBH
"!j'1 'It::' llllc;rgil1g above their brushfield competitors. Understory conifers amidst this dense
hardwood/brush vegetation have a difficult time thriving and are usually sparse and/or suppressed
with little opportunity for long-term survival and growth. Other species that can occur include
snowberry, dwarf Oregon grape. and others. Current vegetational structures are usually dense and
sollcL with brushfield canopies and root zones fully occupied. Often, old Douglas-fir snags killed
durillg the \vildiire event arc scattered throughout a unit, with an even largc;r number ofjackstr,med
dO\vned Douglas-fir logs in various states of decay.
CUlTent \Vildfire Conditions - The dense early seral vegetation of Landscape Unit E is a
vegetational profile well-predisposed to another wildfire, especially when located on very steep
slopes of 50 percent and greater. This should not be surprising since this pattern ofinfrcqucnt, intense
wildfire appears to have been a common disturbance type in this landscape unit, at least since
settlement of the area in the mid-1850's. This disturbance history on these sites results in even aged
vegetational structures, usually continuous in both horizontal and vertical directions. These
continuous fuels on steep topography make the likelihood for intense wildfire extreme. As a result,
opportunities for direct suppression during wildfire events are minimal in this landscape unit.
However, units in this landscape unit are probably less likely to burn than similar vegetational
profiles on more southerly aspects ( e.g. Landscape Unit D ), due to higher humidities, shorter
daylengths, and subsequently decreased length of fire season (due to shadier aspects). There is also
some research information that suggests that deerbrush ceanothus is less flammable than many otht:r
brush species and may reduce wildfire behavior in some situations. However, these slight distinctions
are overwhelmed during most of fire season, when fire conditions allow for intense fire throughout
the duration of the season.
Management Opportunities- Vegetation in this landscape unit is perhaps the most difficult within
the A WUI to manipulate in order to encourage short-term and long-term wildfire management
benefits. In many places, that difficulty probably outweighs any wildfire management benefits that
might accrue, particularly given the steep topography and the difficulty in creating adequate fuel
discontinuities to be effective in a wildfire. Creating horizontal discontinuities in fuels is difficult
because the two primary species that dominate these units- Pacific madrone and deerbrush ceanothus-
are vigorous stump sprouters that rapidly re-colonize a site after manual or mechanical removal
(Note- mechanical removal is rarely employed in this landscape unit due to the steep, inaccessible
topography). Encouraging vertical discontinuity in the vegetational structure is at best a long term
process given the early-seral nature of the existing vegetation, a process that can likely be thwarted
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by a subsequent return fire. Encouraging long-term vertical discontinuity through conifer re-
establishment by planting can be difficult as these native stump-sprouters are aggressive, well-
adapted to the sites, and can thoroughly out-compete planted seedlings, unless they can be controllt:d
within the immediate vicinity of each planted seedling through grubbing (deerbrush ceanothus only),
repeated annual cutting, or through the use of herbicides (see Picture #20). Where possible, releasing
established trees, conifer or hardwood, through brushing, thinning, or other release treatments within
their vicinity, is perhaps preferable to planting of conifers. Overall fuel amounts will be decreased,
individual trees may be less apt to burn in a wildfire event, and vertical discontinuities will result
sooner through these actions. Slash can be piled and burned to further reduce wildfire potential.
Management Issues- Fuels reduction in Landscape Unit E is a fairly straightforward process of
brushing/thinning, piling and burning, although this work can mostly only be done by manual
methods, as most sites are too steep for mechanical methods. However, the steep to very steep nature
of the topography and difficult working conditions make the work physically very demanding,
expensive, and dangerous. Few landowners undertake this type of work on their own. Marketable
products are minimal, if not nonexistent, in this landscape unit, especially given the steep,
inaccessible topography. The minimal benefits from a wildfire management perspective, coupled
with the difficulty and/or high cost, make wildfire management activities in this landscape unit a low
priority for most owners.
Other Resource Issues- The steep topography in Landscape Unit E make slope stability/failure an
important issue to consider whenever vegetation removal is considered on slopes over 50% and/or
when other signs of potential slope failure exist. Obtaining advice/assistance from a professional
engineering geologist is recommended prior to initiating projects in this landscape unit. Fuel
reduction, if desired, is best accomplished in narrow contour strips to minimize the likelihood of
slupL' failure. Vegetation removal in small openings can help improvc species and structural
divc:"';ity- important wildlif'c hahitat valllcs- ~lS \\L'II as increasing access for ~lI1il11als, Small opcnil1t'c'
can also be created around existing overstory hardwoods/conifers, increasing their long-term survival
and growth.
Landscape Unit F- Conifer Plantations - 5 units, 29 acres
Topographical Location- Landscape Unit F occurs at various locations on gentler (15 to 30 percent)
slopes of various aspects in the A WUI.
V cgctation Description - Landscape Unit F is characterized by an uncommon vegetation type in the
Ashland interface area-plantations of conifers. These plantations, mostly dominated by ponderosa
pine, were planted 10 to 25 years ago and are conspicuous blocks on the landscape. If planting
survival percentage was good, ponderosa pine currently dominates 80 to 100 percent of the stand
species composition. These plantations are located in various locations-ridgelines, more southerly
aspects, or in transitional areas close to city limits in which soils gradually change from those
dominated by decomposed granitics to those which contain a much higher percentage of clay. Some
of these pine plantations can actually be off-site-that is, planted in situations and on soils that
typically would not have supported anything more than scattered overstory ponderosa pine, amidst a
more typical oak woodland/savanna vegetation type. Younger plantations, usually initiated after
clearing of existing vegetation, have often been reinvaded by other sprouting or germinating brush
and hardwood species. These developing brush and hardwood species can offer significant
competition for moisture with the developing seedlings, as well as quickly growing into a more
continuous fuel profile- an obvious negative from a wildfire management perspective. Older
plantations with good survival, if left untreated and/or unthinned, can form dense vegetational
profiles highly susceptible to rapid and intense wildfire spread (see Picture #21).
Current Wildfire Conditions - Landscape Unit F provides examples of an intentional and direct
shift in vegetation types initiated by human intervention. This management shift can create both
positive and negative effects from a wildfire management perspective. In most of these plantations,
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initial site preparation (i.e., vegetation removal) to create planting spots significantly reduces fuel
levels and site flammability, especially if the original site is dominated by early seral brushfields,
such as found in Landscape Units C, D, and E. For the short term, these plantations can offer
significant benefits from a wildfire management perspective. With the resulting very minimal fuel
loads, these sites can act like those in Landscape Unit A, offering excellent locations to concentrate
wildfire suppression activities in a wildfire event. As plantations mature, however, they begin to form
characteristics typical of early seral vegetation- dense, uniform vegetational profiles that can burn
rapidly and intensely in a wildfire. Successful ponderosa pine plantations can be particularly
flammable when canopies become interlocking, as pines have needles with high surface-to-volume
ratios and canopies that allow rapid convective air flow. Unmanaged dense pine plantations 10 to 25+
years of age found in this landscape unit can be some of the most wildfire prone of the vegetation
types in the A WUI. Understory vegetation in these developing plantations can be dominated by brush
species, most notably whiteleafmanzanita, which can further exacerbate wildfire susceptibility. Even
understories dominated by grass species can encourage rapid fire rate of spread when the grass cures
in late summer. Although grass fires are usually of low intensity and short duration, the low crown
base heights in unpruned plantations usually makes them more susceptible to crown fire
development.
Management Opportunities - Minimizing fuel continuity in developing plantations is a high
priority from a wildfire management perspective. This can be accomplished by pre-commercial
thinning practices traditionally employed to maintain growth and vigor of preferred leave trees,
followed by an aggressive pruning of limbs to increase crown base height (to 8 to 16 feet if possible)
and create opportunities for future improved log quality (see Picture #22). Vertical discontinuity of
fuels can be created in this fashion if thinning and pruning slash can be chipped, piled and burned, or
perhaps utilized (portable sawmills can be used to cut boards if thinned pines are large enough). The
prl'-.)l1lmcrcial thinning itself should be aggressive enough to create some horizontal discontinuity
he!\' ('en Clllony fl'cls. with 100 to 100 retilinf'c! 11"'es per ;lcrr-' (15 to)O foot sPilcing) tilrgets to shoot
!ClI". Wider spacings will create greater disco:ltinuities in canopy fuels. but lLay open up stands
enough to encourage understory development of ladder fuels in openings. Leaving untreated slash
certainly increases wildfire susceptibility in pine plantations, as crown fire initiation is much more
likely. Untreated pine slash can also serve as ideal bark beetle habitat, increasing insect population~;
that can then initiate a successful attack on retained preferred leave trees. Effective slash treatment is
particularly important in pine plantations.
Management Issues - Pre-commercial thinning in pine plantations requires basic knowledge of
thinning decision making (i.e. preferred leave trees, etc) and practical safety issues. If thinnings are of
a merchantable size, more technical and professional expertise may be needed to harvest, market
and/or utilize (lumber) logs. Utilizing fire to eliminate slash also requires a high degree of
professionalism on sites close to homes and other improvements.
Other Resource Issues - Most of the plantations in the Ashland interface area are located on gentle
slopes close to city limits and thus are not candidates for slope stability concerns. However, there are
occasional plantations on steeper slopes of decomposed granitic soil types, and thinning prescriptions
may be altered to retain more trees if slope stability is a concern. Single species, uniform age
plantations are the least attractive vegetation types for wildlife in general, although dense cover in
unmanaged plantations is used for hiding by some larger animals, such as deer and bear. Leave tree
selection during thinning activities can improve species diversity by leaving more hardwoods and/or
other conifer species, which will subsequently improve wildlife habitat values.
Landscape Unit G - Mixed Conifer & Hardwood, 75-125 Years - 30 units, 312 acres
Topographical Location - Landscape Unit G is typically located on 25 to 45 percent, mostly
southerly/southeasterly aspects, usually on moderately sloped low to mid slope locations at low to
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mid elevations in the A WUI.
Vegetative Description - Landscape Unit G is a vegetationally complex unit with a wide array of
vegetational ages, species compositions, structures and densities. Typically, the sites are dominated
by a mixed overstory of relatively equal amounts ofponderosa pine and Douglas-fir in the 60 to 100
(occasionally older) year age class. These two conifers generally comprise around three-quarters of
the total stand basal area throughout Landscape Unit G. The high percentage of these larger overstory
conifers is indicative of the deeper soils and higher site productivities than landscape units in lower
slope positions (i.e. Landscape Units B and C). California black oak and especially Pacific madrone
are also common parts of the overstory, although the larger conifers (typically up to 24+ inches DBH)
usually are emergent above the hardwood component. Other overstory species include occasional
sugar pine, incense cedar, and on the drier portions of this landscape unit, Oregon white oak.
Typically, overstory trees range from 10 to 18 inches DBH, although structurally the stands in
Landscape Unit G are complex and variable, and usually arranged within multiple cohorts, with trees
of various sizes and ages intermixed throughout. Often these stands can be moderately to severely
overstocked, particularly given the amount of competition for site resources from understory
saplings, small trees, and brush. Understory species are typically dominated by two principal brush
species - deerbrush ceanothus and whiteleaf manzanita, with a variety of other species and
groundcovers. Portions of stands in this landscape unit can be dominated by brush species. In fact, in
many locations, Landscape Units D and G have very similar site capabilities, and the dominance of
whiteleaf manzanita in Landscape Unit D is mostly related to a difference in disturbance history-
namely, more recent higher intensity fire (such as the 1973 wildfire in the Hamilton Creek
watershed), as compared to lower intensity fire in Landscape Unit G. Basal areas average 125 to 175
square feet per acre, although the range can be considerable from site-to-site. Overstory conifers also
range considerably in vigor depending largely on stand density. Douglas-fir appear to be most
affected bv excessive stand densities, and Douglas-fir snags are not uncommon throughout
r ',,' l';C;!l"~ i Illit (I, ~ ~ ~
, I
CUlTcnt Wildfire Conditions - Wildfire potential in the untreated portions of Landscape Unit G are
usually very high for several reasons: 1) the unit is located on primarily southerly aspects that not
only lengthens fire season, but also reduces fuel moisture and increases potential flammability and
subsequent wildfire behavior, and 2) stand structures include high amounts ofladder fuels and
rdati vel) uniform and contiguous fuel profiles in both horizontal and vertical directions. Excessive
snag development in portions of Landscape Unit G exacerbates wildfire behavior and potential
spotting. Gentle to moderate topography in Landscape Unit G is favorable from a wildfire
management perspective and access for wildfire suppression activities is often good.
Management Opportunities - The opportunity to create less wildfire prone vegetation types in
Landscape Unit G is usually good (see Picture #24). Overstory conifers and even hardwoods often
tower above understory vegetation and are vigorous enough to respond to stand density reductions in
their vicinity. Often, non-commercial thinning and brushing alone can reduce stand densities to more
favorable levels form a stand health perspective. (Bark beetle related mortality of overstory conifers
following the 2001 drought year is becoming evident throughout the A WUI, however.) Utilization,
piling and burning and perhaps in some cases prescribed underburning can reduce fuel loads to much
more acceptable levels. The more definite dominance of the larger overstory conifers in Landscape
Unit G offers opportunities for maintaining reduced post-treatment understory development.
However, stands in Landscape Unit G can also often be relatively open in nature, encouraging
understory development and ultimately stand structures with less vertical discontinuity. However,
this same discontinuous canopy profile in horizontal directions can provide wildfire management
benefits if understory development can be controlled. Some of the largest and oldest conifers in the
Ashland interface area (100 to 150 years) can be found in Landscape Unit G. Maintaining these larger
trees through aggressive thinning within their vicinity should be a priority.
Management Issues - Understory thinning, brushing and fuel reduction activities can be
accomplished at the same level of difficulty as other areas dominated by early successional
vegetation. However, moving into the larger, more merchantable size classes will require a greater
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degree of skill and professionalism. Logs and/or lumber from home sawmilling may be able to be
generated from fuels management activities in this landscape unit. Moderate slope gradients and
easier access in many locations tend to increase management options and reduce costs.
Other Resource Issues- Slope stability concerns are generally minimal on these gentle to moderatt::
slopes. Isolated spots that exceed 50-55 percent gradient may be of a slope stability concern and
perhaps require professional assistance from a consulting engineering geologist. Good wildlife
habitat and biodiversity values can be maintained in this landscape unit, particularly given the
inherent species and structural diversity and older age classes of trees. The larger pines and
hardwoods are particularly important to retain (and promote if possible) for these reasons. Re-
creation of a vegetation type more typical of the pre-settlement era is probably more easily
accomplished in this landscape unit than in perhaps any other in the A WUI. Open stand conditions in
established mid-successional forests in the A WUI are rare- hence, their importance on the landscape
level.
Landscape Unit H - Douglas-fir (Dead & Dying)/Pacific Madrone,
75-100 years - 27 units, 207 acres
Topographical Location- Landscape Unit H is located on moderate (25 to 55 percent) primarily
northwesterly to northeasterly aspects, usually in mid slope locations, often in association with steeper
slopes of Landscape Unit J above.
Vegetation Dcsc,"iption - ftlnclscape Unit IT is G trZlllSitionil] type on more northerly Zlspects in the
1\ \\vl il bct'vveen the lower elevation valley cdge types, such ~\s Landscape l'nits D and C, and the
more productive, upper elevation sites of Lanclscape Units E and.r. Vegetational conditions in this
landscape unit and in adjacent Landscape Unit J were very similar twenty years ago, although these
10\\:1' elevation sites contained a higher percentage of hardwoods, and conifers were slightly smaller,
perhaps occurring at greater densities, and thus under greater moisture stress. In effect, much of this
landscape unit could have been considcrcd a lowcr extcnsion of Landscape Unit J at that timc.
However, greater overall site and stand moisture stress in this landscape unit made the conifers
(primarily Douglas-fir) highly susceptible to attack from bark beetles, particularly given the excessive
demities. Extensive mortality has, in fact, been occurring in this landscape unit since the drought
years of the late 1980's and early 1990's (see Picture #25). The area around the upper end of Lithia
Park (Units H5 through Hll) is the classic example of this situation, with 50 to 100 percent mortality
of overstory 8 to 16 inch dbh Douglas-fir already having occurred within individual stands. On the
other end of this transitional spectrum are sites that are currently experiencing initial but ongoing
mortality of their overstory Douglas-fir component, such as Units Hl5 and Hl6 at the upper end of
Morton Street. This disturbance event (i.e., bark beetle related mortality of dominant overstory
Douglas-fir), in response to the lack of disturbance associated with fire exclusion policies and
subsequent excessive stand densities, has resulted in uniquely different vegetational types on the
landscape, hence the separate delineation of Landscape Units Hand 1.. With the demise of the
overstory Douglas-fir, total stand basal areas have dropped significantly, currently averaging 100 to
150 square feet per acre, as compared with pre-mortality totals of 175 to 225 square feet per acre.
Unfortunately, the bark beetles that attack Douglas-fir tend to focus on the larger diameter classes, so
the remaining Douglas-fir tend to be the smaller, suppressed individuals formerly in the understory.
Scattered larger Douglas-fir 12 to 16 inches dbh also exist, although many remain of marginal vigor
and may succumb to bark beetles in the future. The 2001 drought year exacerbated tree decline, and
additional mortality in 2002 is likely. As a result, native hardwoods currently form a much greater
percentage of the existing overstory, typically averaging two-thirds of the total stand basal area, with
Pacific madrone about twice as abundant as California black oak. Douglas-fir snag abundance is
variable in this landscape unit, depending largely on the timing of bark beetle attack and subsequent
mortality. Some units are currently dominated by snags (e.g. Units H3, H4, H16), while others that
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were attacked ten or more years ago have fewer standing snags, but much greater amounts of large
woody debris on the ground (e.g. Units H5 and H6 at the upper end of Lithia Park). The sudden
availability of site resources, most notably water, following stand-level mortality of Douglas- fir, has
resulted in rapid development of understory vegetation, most notably deerbrush ceanothus, poison
oak, snow berry , hairy honeysuckle, and various grasses and broadleaved herbaceous plants. Also
included in this landscape unit are several units that appear to have been dominated throughout their
lives by hardwoods, in particular Pacific madrone in the 5 to 16 inch DBH class, with very little
simultaneous development of conifers. These isolated stands (e.g. Units H20 and H21) have much
higher basal areas, currently supporting 150 to 200 square feet per acre of primarily Pacific madrone,
with only scattered emergent Douglas-fir.
Current Wildfire Conditions - Landscape Unit H has variable wildfire management characteristics,
largely dependent on the amount of bark beetle related mortality of overstory Douglas-fir. In stands
currently dominated by larger hardwoods and a minimal amount of bark beetle related mortality of
Douglas-fir (e.g., Units H20 and H21), wildfire management potentials can be good, given decreased
surface fuels. Existing dense stands will also continue to thwart development of ladder fuels. In a low
to moderate intensity fire event, initiation and/or sustenance of rapidly expanding crown fire is
unlikely. However, a dense canopy of primarily hardwoods could certainly sustain a rapidly
spreading crown fire if one were to enter (rather than be initiated) in these types of stands. As
increasing numbers of snags develop in stands in Landscape Unit H, however, wildfire potentials are
dramatically increased for several reasons: I) snags increase spotting of wildfire, provide a vector for
transporting fire from surface to crown fuels, and can ultimately increase surface fuel loads as snags
die and fall to the ground as large woody debris, 2) developing openings from mortality of overstory
Douglas- fir initiate development of more wildfire prone early-successional vegetation. There is some
evidence that hardwoods may be less susceptible in wildfire events due to physical and/or chemical
characteristics that may retard fire behavior slightly, at least compared to conifers. However,
harchvood~ em ~llso he susceptihle to d:1m~lZC ~\nd!or nwrtality fol1owing ~1 m~\jnr fire tkm ar'~ tlv~
ll1i,~":r-h~ll<cd c()l1ifcr~, Rapid slump sproilil1g fnllowillg 1 Ill; it) ofkllJ\Voods \\illlikcly illSlllC
C()!~t; l1ued chminLlnce nf thi :;pccics on thcx sites, perhaps 1u the continued decline of Douglas-fir in
the species composition.
Management OPPol'tunitics - In stands that still contain Douglas-fir as a considerable portion of
their overstory component, stand density reduction to improve their vigor is desirable, provided they
are still capable of responding. This would be a similar treatment to that described for Landscape
Unit J. On the other end of the spectrum in Landscape Unit H, there are few examples in the Eastern
Siskiyous of older stands dominated by hardwoods (particularly Pacific madrone) that have grown to
an advanced stage of development, making it more difficult to project possible management
directions for these types of stands. Rather, this stand type exists largely because of a change in
disturbance history from frequent, low-intensity disturbance in the pre-settlement era to infrequent,
moderate to high-intensity disturbance today. It is unknown how long Pacific madrone can maintain
individual tree vigor amidst escalating stand densities, but one can assume that those stands currently
at high densities of hardwoods (i.e. basal areas of 150-175+ square feet per acre or more) will
continue to experience mortality over time, with the associated negatives from a wildfire
management perspective. In between these two extremes in Landscape Unit H are the mixed stands
with light to heavy Douglas-fir snag components- in effect, various levels of ongoing stand density
reduction initiated by bark beetles. Additional stand density reduction may be needed in some stands
to meet stand vigor and wildfire management objectives, while others in this landscape unit may
already be at sufficiently reduced stand densities. In those areas throughout Landscape Unit H where
wildfire management objectives are prioritized, snags should be felled and their tops and limbs piled
and burned. If large enough and still merchantable (Douglas-fir can rapidly decay and check, and
become unmerchantable), logs can be sold to mills if harvest and removal can be accomplished in an
ecologically and economically sound fashion. Snags and large woody debris may also be left on-site
for other values (see below), particularly in low priority areas from a wildfire management
perspective (e.g. midslope positions, steeper sites, etc.). Hardwood thinning may be appropriate in
stands that are currently overstocked with hardwoods. Maintaining a sufficient overstory (even of
hardwoods) to retard development of understory ladder fuels is a desirable objective, at least in the
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short term. Utilization (Pacific madrone is the most desired species for firewood in southern Oregon)
and/or piling and burning of thinning slash is highly desirable in order to maintain reduced surface
fuels. Coupled with good crown base heights and increased canopy spacing, this treatment could
improve an already reasonable vegetational profile from a wildfire management perspective. Small
clearings within these stands can also be planted with conifers to try to return conifers to these sites,
although this practice will ultimately result in increased ladder fuels (which may already be occurring
as a result of natural regeneration following overstory mortality.
Management Issues - Landscape Unit H is perhaps the most difficult landscape unit to actively
implement management activities in the A WUI due to a combination of moderate to steep slopes,
poor access, larger trees, and a high number of dangerous snags. Accomplishing management
objectives in this landscape unit will require a high degree of professionalism. Logs, as well as
smaller by-products, may be retrievable from this landscape unit if access is available. Ground-based
equipment should only be utilized on the gentler slopes (up to 25-30 percent) in this landscape unit to
avoid excessive soil disturbance and displacement. On steeper slopes, product utilization will
probably be limited to merchantable logs, and then only if sufficient volumes of timber can warrant
utilization of a helicopter. Selecting leave trees and/or thinning strategies in these highly stressed,
stagnated stands also requires a high degree of professionalism-thinning too few or too many of these
types of stands can produce negative results.
Other Resource Issues - Snags are critical wildlife habitat features that not only serve important
roles standing but also when they fall, becoming large woody debris and serving a variety of
important ecological functions in that capacity. Currently, there are more conifer snags in Landscape
Unit H than in any other location in the A WUI, although it is rare that they are larger than 18 inches
DBH. Although this size class of snags are not as valuable as larger size classes, retention of snags in
this landscape unit is still a priority from a wildlife habitat perspective. Selecting appropriate
locations Cor snag retention that don't conflict with wildfire management objectives is one strategy for
accL)l1lpli~hing both objcctin:s on a landscape basis. To the degree possible, thinning to retain and
promote the larger Douglas-fir in Landscape Unit H is desirable and should encourage more rapid
development of the more valuable larger conifers in the long term. In the interim, it is suspected that
ongoing snag development will continue to occur over time in this landscape unit, as well as
elsewhere in the A WUI. The expanding patch mortality of Douglas-fir has also created a more
structurally diverse vegetatiunal community, as well as increasing plant species diversity within the
stands as early successional vegetation re-establishes in previously more homogenous vegetational
profile. These are important plusses from wildlife habitat and biodiversity perspectives, but certainly
a concern from a wildfire management viewpoint. It is also a concern from a slope stability
perspective, as vegetation removal and subsequent loss of root strength can aggravate slope failure on
failure-prone sites. It is advised that an engineering geologist be consulted prior to initiating
management activities on these steeper or failure prone sites, particularly those that have recently
(within the last ten years) sustained a high amount of tree mortality.
Landscape Unit J - Douglas-fir/Pacific Madrone
75-100 Years - 42 units, 734 acres
Topographical Location - Landscape Unit J is located on 40 to 65 percent (and occasionally
steeper) mostly northerly aspects, primarily in upper slope positions, including headwalls
Vegetation Description - Landscape Unit J is a relatively common type located on moderately steep
to very steep northeasterly to northwesterly aspects in the A WUI. This type, usually initiated after
intense wildfire in 1901 or 1910, is currently dominated by extremely dense Douglas-fir poles 4 to 16
inches DBH, and occasionally larger (particularly at the upper elevations). These stands, grown at
excessive densities throughout their life, are currently at very high densities for these sites, averaging
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175 to 225 square feet per acre basal area. Douglas-fir generally comprise 75 to 90 percent of this
total stand basal area, with the remainder usually comprised of similar sized Pacific madrone that are
rapidly becoming overtopped and shaded out. The Douglas-fir, are moderately to severely suppressed
and of generally very poor vigor, as evidenced by growth rates of 15 to 50 rings per inch and very
small crowns of 20 percent crown ratio or less. In this condition, many of these trees and stands are
ripe for a serious outbreak of bark beetle related mortality, such as has occurred in the slightly less
productive sites in Landscape Unit H below. In fact, mortality of Douglas-fir is occurring in this
landscape unit, particularly at lower elevations or in transitional areas (unit edges) with Landscape
Unit H or other less productive landscape units. Understory vegetation is usually sparse, except in
snag -related openings where invading early seral vegetation develops. Site productivities are the best
on these northerly aspects of any of the landscape units in the interface, particularly those at the
higher elevations.
Current Wildfire Conditions - Landscape Unit J is comprised of stands of conifers that have good
wildfire management characteristics, if they can be retained. Surface fuels are low and height to
crown base is very high, typically 35 to 60 feet. However, the excessive stand densities throughout
most of the unit insure that snag development and subsequent openings will continue to occur, both
characteristics that can rapidly escalate wildfire behavior. Once crown fire is initiated in these stands
on steeper slopes, it can often easily spread as crown fuels are both excessive and continuous. The
potential for considerable bark beetle related mortality in these overstocked stands can create
excessive snags and ultimately produce perhaps our most wildfire prone landscape unit (e.g.,
Landscape Unit H)-steep slopes covered with standing snags and jackstrawed downed snags
intermixed amongst highly flammable early seral vegetation that establishes following mortality of
the overstory component. If at all possible, avoiding this scenario through stand density reduction and
maintaining existing favorable wildfire management conditions is highly desirable.
Managcmcnt Opportunity - Stand density reduction in the overstocked stands of Landscape Unit J
is th~ obvious managemcnt priority. Somctimcs, this can bc accomplished solely through non..
coml1lercial thinning of suppressed coni krs and understory hardwoods. Howevcr, on morc
productivc sites, particularly those at highcr elcvation, achieving appropriate stand densities will
require removal of conifers of merchantable size classes. Topographic reality, erosive soils, and
limitcd :JCcess in most situations suggest that helicopters would be used in commercial harvest
aCii \ j tics. Stands should bc thinncd to densities that will release prefcrred leave trees and allow them
to improve in growth and vigor, while simultaneously remaining dense enough to discourage
development of understory ladder fuels. Once this is accomplished, the stands in Landscape Unit J
will retain excellent structural characteristics from a wildfire management perspective, with high
distances to crown base and excellent vertical discontinuity of fuels (see Picture #28). Even crown
fuels can be reduced, although great care should be taken not to open these stands too excessively as
they can easily shock and/or tip over due to their high height-to-crown ratios. Removal and/or
burning (pile burning or perhaps prescribed underburning) of thinning slash is imperative to maintain
an effective fuel reduction zone. In areas where dense snags have already occurred, snag removal has
to be coupled with management activities such as described in Landscape Unit H. Some snags can be
retained for wildlife habitat values in locations where wildfire management is not a critical priority,
although most snags in Landscape Unit J are small (14 inches DBH or less).
Management Issues- Landscape Unit J (along with Landscape Unit H) is probably the most difficult
landscape unit in the A WUI in which to accomplish vegetation and wildfire management objectives.
Steep topography and associated access and safety issues, larger vegetation size classes, sensitivity of
the existing sites and stands to manipulation, and the potential commercial value of some of the
conifers to be removed all suggest that great care and a high degree of professionalism be utilized
when implementing management actions in Landscape Unit J.
Other Resource Issues - Steeper slopes in Landscape Unit J are prone to slope failures and
subsequent development of debris slides, potentially impacting structures and other property and
resource values below. Openings in stands, either intentional or via insect/disease attacks, can
exacerbate this possibility. Professional assistance via an engineering geologist is recommended prior
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to initiating work throughout most of this landscape unit, particularly on those sites above 50 to 55
percent gradient. Stand density reduction in Landscape Unit J should open some growing space,
improve light availability, and increase plant species diversity- important wildlife habitat and
biodiversity objectives. If these stands can be retained, if not promoted, through stand density
reduction, they offer the best likelihood in the A WUI of providing mid to late successional values in
the future. Harvest of any merchantable timber in this landscape unit should be done in ways (e.g.
helicopter) that minimize soil disturbance on these steeper slopes.
Landscape Unit K - 15 units, 155 acres
Topographical Location- Along creeks and draws throughout the A WUI, most of which flow in a
northerly to easterly direction.
Vegetation Description - Landscape Unit K comprises the various aquatic and riparian ecosystems
within the A WUI. Riparian and aquatic ecosystems primarily include creeks and streams (aquatic
ecosystems) as well as transitional areas (riparian ecosystems) between aquatic ecosystems and
adjacent upland or terrestrial ecosystems. In the A WUI, most waterways are seasonal in nature,
primarily running surface water only during the winter months. The one major exception is Ashland
Creek, which runs water year-round and has the most well-developed aquatic and riparian ecosystem
values in the A WUI. Tolman Creek, Hamilton Creek, and Roca Creek are three other largely seasonal
creeks south of Ashland Creek that drain the slopes above town. Although these three often do not
run surface water in the late summer season, they do support high levels of groundwater throughout
the year. The vegetation that thrive in these situations is unique and contains species that are not
found elsewhere in the area. These include tree species such as Oregon ash, black cottonwood, red
alder. bigkaf maple, and willow species, as well as other plant species including mock orange,
ninehark. horsetails. sedges, rushes, and ()thers. Also included in riparian ecosystems arc most of the
other species native to adjacent uplands, particularly growing in the upper portions of the riparian
ecosystem. Exotics such as Himalayan blackberry and English ivy have also become well established
in many riparian habitats, often to the exclusion of other native species. This complex of vegetation
offers the greatest species and structural diversity in the A WUl.
Current Wildfire Conditions - Wildfire potentials in riparian habitats are generally reduced from
adjacent upland areas on a landscape basis. The reason is obvious-higher humidities, cooler
temperatures, and the high amount of perennially available water allows for vegetation with higher
moisture levels than elsewhere on the landscape, and for far longer periods of time, thereby
shortening the fire season. Nonetheless, wildfire is certainly a potentiality in these areas, increasingly
so as the size of the aquatic ecosystem decreases. Minor draws higher in landscapes can often burn
just as intensely as adjacent uplands. In the A WUI, as in many areas, the importance of retention of
vegetation in riparian ecosystems for hydrological, ecological, aesthetic, and other reasons is perhaps
greater than elsewhere in the landscape. Unfortunately, retention of this high amount of vegetation,
often occurring in a structurally diverse fashion with multiple canopies and significant vegetational
continuity, can also result in increased wildfire behavior, intensity, and rate of spread. In the A WUl,
dense, highly flammable wildland vegetation extends the farthest into the urban areas of Ashland
within the riparian habitats along the major creeks and streams. In these locations, balancing wildfire
management goals with other significant and important values in riparian/aquatic ecosystems will be
a real challenge.
Management Opportunities/Management Issues/Other Resource Issues - The aquatic and
riparian portions of almost all landscapes in the western United States have come under dramatically
increased attention and pressure within the last 10 to 20 years because:
(1) Availability of large quantities and quality of water is becoming an
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increasingly valuable, albeit rarer, commodity, being highly desired by municipal,
industrial, agricultural, commercial, and residential users.
(2) These areas inherently contain high recreational and developmental potentiaL
(3) Riparian ecosystems contain habitat values that are not only unique on the
landscape but are also the habitat type that has often been most abused, and
subsequently diminished, both in terms of quantity and quality.
(4) An increasing number of species have decreased dramatically in abundance
(most notably salmonids) such that regulatory mechanisms have been instituted
and are continually being upgraded to protect riparian and aquatic ecosystems and
the threatened or endangered organisms that depend on them.
(5) These areas can act as buffers during floodstage flows, helping absorb the
destructive energy of excessive water.
This report is not designed to present detailed descriptions or management recommendations for
these critically important and inherently complex ecosystems. However, it is important to fully
understand the important inherent values that exist in functioning aquatic and riparian habitats. In
many cases, in this landscape unit, the management choice to do nothing will still retain many
critically important values.
The presence and functioning of great numbers and diversities of vegetation, many of which are only
found in these aquatic/riparian ecosystems, provides for a unique vegetational community. Its
associated diversity, seldom found elsewhere in the landscape, simultaneously provides for
disp:()portionately large numbers and diversities ofviildlife species-much greater than for any oth'.:r
habil:lt type. Good riparian habitat usually supplies all orthc basic components of good wildlife
habitat: food. cover, and most importantly water. Cover is often well developed along riparian areas.
This is fortunate because all animals are highly dependent upon year-round water sources
(particularly in droughty southern Oregon), and this cover provides the necessary protection around
these highly used areas, as well as providing access corridors for migration and dispersal. Too, the
location of long, thin riparian habitats along stream courses allows for a high percentage of ecotonal
boundaries (edge effect) where wildlife species have access to multiple adjacent habitat types.
Several wildlife species are only found in year-round sources of water. Amphibians are particularly
dependent on sources of water and, along with some reptiles (such as western pond turtles, a rapidly
declining species) spend most of their lives in water, particularly relying on it during reproduction.
Bird densities are over twice as high in riparian habitat as in adjacent upland habitat, a particularly
important figure influencing rapidly declining populations of neotropical songbirds. Perhaps most
important are the influences that healthy aquatic and riparian ecosystems have on native fish
populations, particularly salmonids, although this effect is mostly downstream from the creek
systems in the A WUI.
Healthy riparian systems also perform important functions relating to water quantity and quality, as
well as mitigation of erosional effects. Streamside vegetational buffers improve overall water quality
by acting as natural filters to trap water-borne sediments, excess nutrients, and pollutants pulsing
through the system via streamflow, groundwater flow, or being carried overland. This function helps
minimize the downstream development of algal blooms, low oxygen levels, and other water quality
deficiencies that can negatively affect all types of aquatic life, including native fish populations.
Riparian vegetation also acts like a natural sponge to reduce floodstage flows, a critical benefit for the
Ashland community. Riparian vegetation also creates a beneficial microclimate which prolongs the
average flow for longer periods of time, even into summer when low flows are the greatest threat to
aquatic organisms. The greater proliferation of roads, skidroads, driveways, and other bare soil
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surfaces within a watershed encourage much more rapid movement of water through the hydrologic
system, thereby encouraging more rapid accumulation of high peak flows in major storm events. A
potential for greatly accelerated erosion in creek and stream channels results, with dramatically
increased amounts of sediment and debris scouring drainages, significantly increasing flood effects
and sediment entry into major streams, with significant deleterious effects on fish populations by
clouding the water, suffocating fish eggs placed in gravel spawning beds, damaging delicate gills of
fish, and degrading habitat for the aquatic macro invertebrates (larval forms of aquatic insects) upon
which fish populations depend for a food source. Downcutting can also lead to lowering of
groundwater tables and subsequent reduction in adjacent meadow, pasture, or forestland productivity.
Establishment and maintenance of riparian buffers subsequently becomes that much more important,
as its "buffering" effect helps to reduce creek flow intensity, velocity, and associated erosion and is of
critical importance during major storm events. Conversely, destruction of riparian vegetation along
stream courses reduces this buffering effect, accelerating downcutting of the stream channel.
Vegetation in riparian buffers also provides stream shading which lowers water temperatures,
especially in lower reaches where higher water temperatures stress native fish and encourage
deleterious algal blooms. Overhanging vegetation also drops leaves, twigs, and insects into the water,
providing food sources for aquatic insects and ultimately all other organisms higher up the food
chain.
To protect and/or improve the aquatic resources, numerous practices have been employed within
stream and riparian ecosystems. Key practices include the following:
I. Leaving large trees to provide shade, stabilize streambanks, and provide future
large woody debris. Large wood provides many structural and biological benefits
in complex stream habitats, including fostering of pool development, dissipation
of hydraulic power of streams, helping to store sediments and gravel for spawning,
providing hiding cover and encouraging development of off-channel l1abitat (low
\e!oc;ty refuges) during high tlo\\S, slcmjng transpo:t uf sediment and bedload,
trapping ~lI1d retaining organic debris. providing a food source itself Cor aquatic
macroinvertebrates, and others. In some situations, large woody debris or rocks
can be added to stream channels to create complex in-stream structure, thereby
providing future hiding, resting, feeding, and rearing habitat in those fish-bearing
creeks (only Ashland Creek in the A WUI).
2. Adding future shade and large tree development by planting conifers in denuded
portions of streams. Many riparian buffers have had conifers systematically
removed and are currently dominated by hardwoods, shrubs, and other non-
coniferous species. These not only provide much smaller forms of debris, but arc
generally much less resistant to decay, thereby reducing their effectiveness at
improving structural complexity in streams. It is important to note that conifers do
not necessarily regenerate and succeed hardwoods without additional disturbance
(i.e., cutting) to create gaps where they can get a start.
3. Planting other streamside vegetation (e.g., willows or other riparian vegetation)
to stabilize eroding banks or downcutting channels and reduce inputs of sediments.
4. Shift vegetation away from dominance by aggressive, non-native species such
as blackberry, ivy, and others.
5. Preventing unnecessary additions of excess sediment through such upland
management practices as: careful and professional planning and construction of
new roads; creation and/or maintenance of adequate road drainage facilities so that
water and sediment are diverted rather than flowing directly dowmoad;
minimizing road or skid road use during periods of high rain or snowmelt; and
constant monitoring of road drainage facilities, particularly during major storm
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events when the greatest amount of erosion, sedimentation, and watershed
deterioration occur.
6. Returning streams to their original channels where past management endeavors
have intentionally or unintentionally altered their course.
These more traditional management practices employed to improve riparian and aquatic habitat
values may have to be modified in portions of the A WUI if wildfire management objectives are
prioritized. Left untreated to minimize wildfire potential, it is possible that these locations could burn
more intensely than elsewhere on the landscape-an unfortunate outcome from multiple perspectives.
The principles of stand density and stand structure, and their relationship with wildfire behavior,
apply in riparian habitats as directly as elsewhere in the A WUI. Retention of highly wildfire prone
vegetational conditions within riparian/aquatic ecosystems is particularly undesirable within the
urban setting, where rapid wildfire escalation could have dire consequences.
Creating vegetational and fuel discontinuities could be utilized in this landscape unit as elsewhere in
the A WUI, hopefully while retaining other important values. A secondary option would be to
implement heavier vegetation and fuel reductions adjacent heavily vegetated riparian habitats.
Removal of Himalayan blackberry alone in many riparian habitats could improve wildfire
management potentials by reducing these ladder fuels.
Use of other more moisture sensitive species, such as mosses, lichens, and bryophytes, as indicators
to determine gradations of riparian influence is an important emerging management strategy that can
guide the size of the area where riparian management guidelines should apply.
B. Landscape Level Analysis of A WUI
The pre\'ious section described methods by which quantitative hazard assessments can be made ll)r
anyone location \vithin the A WUL 'fhis scale of analysis is important to decipher each location's
relative potential for initiation and/or contribution to wildfire bchavior.
Wildfires today, however, are typically mLlch larger than the fine scale unit delineations used in this
report. Wildfires in the 1,000 to 10,000 acre scale have become commonplace in southern Oregon in
the last 50 years. This is the type of wildfire event that is the highest priority to try to avoid in the
A WUI for the variety of reasons previously described. In these types of wildfire events, cumulative
effects of wildfire behavior can create a much different type of fire than those only involving single,
smaller locations. Similarly, the cumulative analysis of vegetative types and wildfire susceptibilities,
coupled with resulting reductions from active management activities, can create a different set of
issues and opportunities than when simply analyzing individual locations. A landscape level
approach to wildfire management, both in terms of preventative measures and during an actual event,
is necessary to minimize negative impacts and effects associated with large scale, high-intensity,
vegetation replacement wildfire.
On a landscape level within the A WUI, there are key areas where existing site conditions
(vegetational profiles, topography, access limitations, etc.) allow for the greatest opportunity for
suppressing escalating wildfire behavior. Implementation of pre-suppression management activities
within these individual units could be particularly effective in minimizing the size and/or intensity of
a wildfire, its subsequent effects on important values. In addition, there are other areas of critical
concern where vegetation manipulation to achieve wildfire management objectives could
significantly increase the potential protection of important homes, improvements, or resource values.
Wildfire management and fuel reduction within these areas are management priorities; that is, these
are areas where the greatest benefit per given unit of cost can be obtained.
Within the A WUI, there are also key areas that offer specific tactical opportunities for effective
suppression during a wildfire. These are generally areas that currently have favorable fuel and
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vegetation profiles from a wildfire management perspective, as well as reasonable access for
utilization of them during wildfires. Effective utilization of these tactical opportunities in a wildfire
could be critical in minimizing losses oflife, property, and/or resource values.
The delineation of management priorities and tactical opportunities in this report is not exhaustive,
and it is fully acknowledged that other important locations for the above may exist as well. It is also
recognized that management priorities and tactical opportunities will change with time as vegetation
grows and/or is altered, and/or other wildfire management practices are implemented
It is also important to note that this landscape level analysis focused strictly on existing site,
fuels/vegetation, access and other wildfire management conditions regardless of existing property
boundaries. The management priorities and tactical opportunities that follow do not take into account
opportunities and/or difficulties that result when objectives and desires of individual owners are
considered. It is critical to understand that the effectiveness of any landscape level wildfire plan, or of
the specific management priorities or practical opportunities suggested, will ultimately depend on
community level acceptance and involvement, particularly by the A WUI residents affected.
The following suggestions for management priorities and tactical opportunities are also strongly
affected by the quality and extent of wildfire management practices implemented in areas adjacent to
the A WUI. Within the city limits of Ashland, numerous activities can decrease both the likelihood,
extent, and severity of fire when it occurs. Creation of defensible space around homes on the
urban/suburban fringe close to the A WUI is particularly important. Other important factors include
access and associated response time, wildfire suppression capabilities, dwelling density, firesafe
construction practices, and others
In the other direction, the effectiveness of wildfire management practices on a landscape level will be
stnmgly int1uenced by coordination with the U.S. Forest Serviee on lands above the 1\ \vUI. 1\ key
use 'll.this report lies in its potential to interJ~lce with U.s. Forest Service 11re management plannil;::,
and on-the-ground activities on lands adjacent to the A \vUl. To be effective, fire management
pbn:ling must work across jurisdictional boundaries to allow for landscape scale prioritization and
implementation ofpre-tlre treatments, as well as suppression activities in a wildfire.
1. Management Priorities for Pre-Suppression Activities
Management Priority #1
This area comprises a major topographical ridgeline separating the Wrights Creek drainage from the
Ashland Creek drainage. The 4,000-acre 1959 wildfire, driven by up-valley winds in the Bear Creek
Valley, crossed at this location into the Ashland Creek watershed, turning southeast and racing
unimpeded upcanyon into the Ashland watershed. Intensive fuel reduction in this location would
allow the first suppression opportunity to try to prevent a recurrence of this event and subsequent
threatening of homes and lives in the Ashland Creek canyon, as well as critical resource values in the
Ashland watershed. Development of this fuel reduction zone would concentrate on breaking up
horizontal fuel and vegetation continuity currently in early successional stages. This fuel reduction
zone could utilize favorable wildfire management zones at the upper end of Wrights Creek (Tactical
Opportunity #1) and work the ridgeline adjacent Hitt Road well up into the U.S. Forest Service
ownership. This fuel reduction zone would provide a distinct opportunity for compartmentalizing a
developing wildfire into a discreetly smaller event.
Management Priority #2
A major area of untreated wildland vegetation extends northerly along a small knob/ridgeline
separating the Wrights Creek drainage from the main Bear Creek Valley. Recent development in the
Wrights Creek drainage is beginning to encircle this knob, making the presence of the highly
wildfire-prone vegetation that much more ominous in a wildfire event. Area-wide fuel reduction in
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this location can hopefully prevent wildfire from spreading from the Wrights Creek drainage into the
more urban settings to the east, or vice-versa. Recent fuel reduction work in this area (Units
C2,C4,C5,H1) has begun a fuel reduction zone that could be a significant suppression opportunity in
a wildfire event, as well as protecting homes in the vicinity. Although more vegetation and fuels
reduction could be done in these treated areas in the future, they serve as a sample of a good first step
in a proactive wildfire management strategy for the area.
Management Priority #3
The largest area of fuels of extreme hazard in the A WUI exists on the moderately steep to very steep
easterly aspects west of Ashland Creek. This area was mostly burned at high intensities in the 1959
wildfire. Existing early seral vegetation that has since returned to the area is once again an extreme
hazard, with subsequent likelihood for a return of high-intensity wildfire. A wildfire in this area could
threaten not only homes west of Granite Street, but also important resource values upcanyon in the
Ashland watershed. In 1959, wildfire intensity was low in the areas immediately above the homes
along Granite Street (perhaps these areas were intentionally backburned to prevent wildfire spread
into the urban area). Existing vegetation in Units 11,G 1, and J2 currently comprises primarily older
conifers and hardwoods that offer good possibilities for creation of vertical fuel discontinuities and
favorable stand structures from a wildfire management perspective. Stand density reduction through
understory thinning in this location, followed by excellent slash treatment, could accomplish this goal
whilc improving the health and vigor of the remaining overstory trees. Completion of this work
would create a fuel reduction zone running from existing grasslands in Unit A6 south to a fuel
reduction zone described in Management Opportunity #4.
Management Opportunity #4
.\ics or fuel reduction zones and tactical opportunities have been created by the U.S. Forest
.~ . .:,:ti:cl the City of Ashland upslope, perpendicular to, and on the west side of Ashland Creek
(Lji:; :) l;2/D11/E4: G8/E6; U.S. Forest Service fuclbreak in southwest quarter of Section 16). Each or
thes,.' provide an opportunity to utilize suppression tactics to check wildfire advancing upcanyon
towmds the valuable Ashland watershed. Fuel rcduction in tvfanagement Opportunity #4 would
provide yet one more opportunity to check this advance. Multiple opportunities are highly desirable
because it is never known what time of day (with resulting fire intensity) the advancing wildfire wi] I
reach a fuel reduction zone. This management opportunity could be particularly effective because it is
a relatively broad area on more moderate slopes with generally reduced site productivities and
vegetation abundance-all features that lend themselves to fuel reduction zone effectiveness,
particularly in this area where utilization of fuel reduction zones in a wildfire event is problematic
given the dense early successional vegetation and extreme fire hazard on very steep slopes. This fuel
reduction zone could also tie into Management Opportunity #1 at the top, allowing potentially more
effective compartmentalization of wildfire. Fuel reduction in the lower (easternmost) portion of this
management opportunity is particularly important in providing protection for the Ashland Creek
Drive subdivision (see Picture #31). Work would primarily entail manual brushing, and piling and
burning to create horizontal fuel discontinuities. Once completed, this management opportunity
would tie into Management Opportunity #3 at its bottom (easternmost) portion, providing yet another
opportunity for compartmentalization of a developing wildfire. Slope stability issues in this area
above Ashland Creek subdivision will have to be addressed, however.
Management Priority #5
Management Priority #5 comprises the single most significant extension of wildland vegetation into
the urban area of Ashland-that being the upper slopes of Lithia Park immediately above and east of
Ashland Creek. This is a major area of dense, fire prone vegetation of high to extreme hazard
adjacent an area of considerable human use with its associated extreme risk of ignition. Wildfire
behavior could escalate dramatically in this area, particularly if strong upslope or upcanyon winds
were occurring-not an unlikely scenario in a wildfire event. Rapid escalation of wildfire behavior
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upcanyon could threaten homes south of this unit and perhaps challenge the effectiveness of fuel
reduction efforts undertaken south of this unit (primarily on City of Ashland lands) in the throat of
the Ashland watershed. Also potentially threatened could be homes along the ridgetop east of this
unit, along Ridge and Terrace Streets. Fortunately, good fuel reduction work recently completed
along Glenview Street has reduced this possibility and provided an accessible opportunity for
suppression response (see Tactical Opportunity #5). Continuing this type of vegetation manipulation
and fuel reduction throughout this Management Priority could significantly minimize wildfire
potential. It must be noted that in the absence of other stand density reduction activities, significant
insect-related mortality of almost all overstory Douglas-fir in this area occurred during the drought
years of the early 1990s. These dead trees were felled to minimize their contribution to wildfire
spread, although they currently contribute significant fuel loading on the ground, particularly in the
south half of the area.
Management Priority #6
Mountain Park Estates is a planned unit subdivision at the top of Morton Street that extends well up
into wildland vegetation types in relatively steep topography. Although some management to reduce
wildfire hazard has been accomplished in the vicinity, this area is surrounded on portions of all sides
by highly flammable, wildfire-prone vegetation types. Several stands (Units H16, HI7) of severely
overstocked Douglas-fir/Pacific madrone are located in close proximity, each with a significant
number of recent snags, a process which will undoubtedly continue. Wildfire-prone dense early seral
vegetation (Units CI4, CI5, DI6) is also located in close proximity. Both of these vegetation
conditions can produce extreme wildfire behavior, particularly in steeper topography such as occurs
here. Of additional concern is an extended wildland vegetation type downhill from the subdivision
(Units C 14/]26). Wildfire in this occluded interface would not only threatens homes within and
immediately adjacent it, but also can contribute to rapidly escalating wildfire behavior in uphill
directions (towards Mountain Park Estates). Manipulating vegetation to achieve wildfire management
objectives are described in this report for Landscape Units 2.3.6.7. and 10. which all occur in close
prl)\:mit:, to this location.
Management Priority #7
Similar to Management Opportunity #6, this location is another instance where dense, wildfire-prone,
wildland vegetation extends into a more urban/suburban setting at the upper end of Beech Street.
Residences on all sides and within this vegetation are susceptible to rapidly developing and/or
encroaching wildfire. Vegetation manipulation to create more wildfire resistant vegetational types
would be appropriate in this area. Vegetation manipulation on a broad, gentle ridgeline between two
seasonal creeks west of Beech Street (Units C 16, D 17) could create the type of fuel reduction zone
that could be extremely valuable in a wildfire event. The more easterly of these two draws (Unit Kl 0)
contains dense riparian vegetation very close to homes along Beech Street. Accomplishing wildfire
management objectives through vegetation manipulation while maintaining maximum riparian
habitat values can be difficult to accomplish (see section on Landscape Unit K), but may be
particularly important in this location.
Management Priority #8
Two relatively large areas of early seral vegetational communities dominated by whiteleafmanzanita
and Pacific madrone are located adjacent Ashland city limits on either side of Elkader Street. These
extreme fire hazard types were initiated following the 1973 Hillview fire, which ultimately consumed
about 750 acres, was initiated by arson at the very bottom of Unit ElO and spread rapidly up and into
the Hamilton Creek watershed in a very hot, high intensity wildfire. Brushfields in both units could
easily create a similar wildfire scenario, threatening not only homes in the immediate vicinity but also
residents at the upper end of Elkader Street and Timberline Terrace above these wildfire-prone early
seral vegetation types. This is particularly unnerving given that these two streets offer the only
vehicle access for these residences; hence, the possible disastrous scenario of having to drive through
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an advancing wildfire in order to escape. Wildfire management opportunities to reduce wildfire
danger in these brushfields is described for Landscape Units D and E elsewhere in this report. Two
units of Landscape Unit H (Units H20, H21) are also located adjacent and intermixed with houses in
this area. These units, dominated by older overstory hardwoods, have reasonably favorable stand
characteristics from a wildfire management perspective (low surface fuels, minimal ladder fuels), but
generally have very dense canopies that could carry fire in a wildfire event. Light to moderate stand
density reduction could decrease this continuous fuel profile while minimizing ladder fuel
development (see section on Management Opportunities for Landscape Unit H). Excellent slash
treatment in all these areas would be imperative.
Management Priority #9
Flammable vegetation types also extend well into the urban/suburban portions of Ashland along Roca
Creek. Fortunately, a considerable portion of this area has been maintained as pastureland (Unit
AI5), a highly favorable vegetation type from a wildfire management perspective, particularly if
irrigated during summer. The narrow riparian buffer with limited vegetational development at the
bottom of Unit A 15 probably also contributes to a less wildfire-prone condition. Although fire
intensity and/or duration is not high in this vegetation type and can usually be easily suppressed if
firefighting equipment can reach the site, fire rate of spread can be very fast in dryland pastures or
grasslands. Running quickly uphill or upcanyon, it could possibly spread into fuel types above Unit
A 15 (the older overstory trees in Unit H19) that could rapidly escalate wildfire behavior into the
crowns and ultimately into the subdivision to the east (which also supports a fairly dense canopy of
ovcrstory trees), as well as parcels and structures to the south as described in Management
Opportunity #8 Maintaining irrigated pasture in Unit A 15 for as long as possible in the summer
season would be an excellent wildfire prevention strategy. Stand management activities such as
described for Landscape Units Band H could decrease the potential for crown fires in Units B 16 and
1 I 1 C)
i\b;; ag~ 111 en t Priority #10
! la:~1ilton Cr,-'ck is the second largest riparian habitat (after ^shland Creek) with associated wildland
vegetation to extend down into the urban/suburban area of Ashland. This vegetation type extends all
the way to Siskiyou Boulevard and provides many important values in the urban/suburban context
(wildlife habitat, vegetation buffering and flood stage control, aesthetics, open space, recreation, etc.).
In dry summer conditions, however, these riparian corridors can rapidly escalate wildfire behavior
and even become a corridor for wildfire themselves. A similar situation was described for
Management Opportunity #4 (upper Lithia Park). Actual management to minimize wildfire potential
and impacts mayor may not be desirable when the multiplicity of other values are considered.
Nonetheless, it is important that this area (Unit K14) be identified and analyzed when considering
potential wildfire concerns. Areas adjacent the upper portions of Unit K14 also contain an important
management opportunity. Fuel reduction in the uplands immediately adjacent and west ofthe riparian
habitat of Hamilton Creek could help prevent spread of wildfire across the canyon such as occurred in
the 1973 Hillview Fire. Slope gradients are gentler on the west side of the creek, making fuel
reduction benefits more compelling than on the steeper eastern side of the creek. Good access is also
available paralleling the creek for almost its entire length. An effective fuel reduction zone in this
location could help compartmentalize a developing wildfire and subsequently reduce the likelihood
of wildfire spread into the Ashland watershed or other forested areas upslope.
Management Priority #11 - Throughout the Interface
Two management priorities exist throughout the A WUI and are combined under this category. These
are:
I. Roadside clearing of excessive flammable vegetation along all major roadways in the A WUI
should be a management priority. These locations are high probability locations for fire
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ignition from accidents, arsonists, cigarettes, etc. Reducing the flammability of roadside
vegetation will increase the likelihood that timely response may be able to suppress the
developing fire before it escalates and becomes uncontrollable.
2. Ongoing maintenance of all currently delineated tactical opportunities to insure their continued
utilization and effectiveness in a wildfire event.
2. Ta~1icaLQID!()!,!!!!!ities for Wil51fire Suppression
Landscape level mapping of the A WUI has provided some clear opportunities for tactical suppression
in a developing wildfire event. The following areas have been delineated because the vegetation/fuel
complex is such that fire intensities and rates-of-spread would likely be decreased in a wildfire event,
offering opportunities for control. Identifying and ultimately linking these areas through appropriate
wildfire management activities should improve opportunities to minimize and/or compartmentalize
wildfire behavior and potential deleterious impacts in a wildfire. Currently these areas can be
identified on the map as areas of naturally low fuels (green) or areas where implemented management
activities have produced more favorable conditions from a wildfire management perspective (green
icons overlaying individual units). However, many other factors not considered here (access and
response time, available equipment and personnel, proximity of important values-at-risk, landowner
cooperation, etc.) would additionally determine potential utilization of these tactical opportunities in
a wildfire event. It is important to note that the potential effectiveness of these tactical opportunities
will vary with effectiveness of treatment, as well as both diurnally and seasonally, each producing
resulting changes in associated wildfire behavior.
Tactical Opportunity #1
Extensive grasslands and old orchards/ag lands at the top ofWrights Creek (Units A3, A4, A5) and
low fuel zones (Units B3, B4) offer a large contiguous area oflow to moderate wildfire hazard (see
Picture #32), and an excellent opportunity to check wildfire advancing upslope from the north (i.e.,
the path of the 4,OOO-acre 1959 wildfire). Recent work in the adjacent woodlands to the east has
further expanded this fuel reduction zone, extending it to and tying in with Tactical Opportunity #2 to
the southeast in the Ashland Creek canyon. Completion of Management Priority #1 would
dramatically improve the effectiveness of Tactical Opportunity #1 in preventing wildfire expansion
from the north in Wrights Creek into the Ashland Creek drainage.
Tactical Opportunity #2
Recent wildfire management activities completed along Strawberry Lane have produced a fuel
reduction zone that ties together the Wrights Creek drainage (see Tactical Opportunity #1) with a
reduced wildfire hazard zone (Unit A6) in the Ashland Creek drainage. This area could be expanded
by completing additional fuels reduction in Units B5 and B6, although fuels are already fairly low in
these oak woodlands. This would help prevent wildfire spread downslope towards residences above
Granite Street. Completing Management Opportunity #2 would dramatically extend the fuel
reduction zone to the south, beginning with TO #2 and extending upcanyon in the Ashland Creek
canyon.
Tactical Opportunity #3
Fuels reduction activities completed by the City of Ashland on their lands in the "throat" of the
Ashland watershed (primarily in Section 16) have provided a sizable fuel reduction zone in which
suppression activities could be concentrated in a wildfire event. An "area-wide" approach to fuels
reduction has been completed in an area over one-half mile wide on the east side of Ashland Creek.
This has included brush removal and understory non-commercial thinning, followed by piling and
burning of resulting slash. On the north end, this is incorporated into a pasture on private land (Unit
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A9) that further improves the tactical opportunity. Similar activities have been conducted on the west
side of the creek, although not as extensively largely due to very steep slopes, topographically
unfavorable locations for wildfire management activities, and slope stability issues. Several key areas
have been treated on the west side, however, creating smaller fuel reduction zones with which to
concentrate suppression activities during a wildfire. The northern-most of the two is clustered around
a City of Ashland quarry-an excellent fuel break and the first opportunity on the west side of the
creek to suppress a wildfire spreading upcanyon. The southern-most portion of TO #3 (Units G8 and
E6) is in a particularly useful topographical location for a fuel reduction zone and will hopefully soon
"tie in" to a shaded fuelbreak on adjacent U.S. Forest Service land (fuel reduction work for this small,
untreated area between the two shaded fuelbreaks is planned in the upcoming U.S. Forest Service
project). Tactical Opportunity #3 is a key location for the ultimate protection of a major wildfire
intrusion into the Ashland watershed. Obviously, ignition source is most likely in the urban area
immediately north and below Tactical Opportunity #3. Upcanyon winds will likely force any wildfire
initiated downcanyon into this location (such as occurred in 1959). If a wildfire is able to break
through this narrow portion of the Ashland Creek canyon, airflow restricted by topographical
influence would exert considerable pressure on the upcanyon side, likely rapidly escalating wildfire
behavior into the larger Ashland Creek watershed.
Tactical Opportunity #4
Several other large fuel reduction zones created by area-wide non-commercial thinning, brushing,
piling and burning, and/or prescribed underburning have been implemented on City of Ashland lands
in the canyon along Ashland Creek below Reeder Reservoir. Each of these comprise larger areas that
may be effective in most wildfires in preventing wildfire spotting and spread. The southerly-most of
the two is particularly important because of its location at Reeder Reservoir. Stopping a wildfire
advancing upwards into the watershed is particularly critical at this location because the watershed
spreads into two major drainages, East and West Fork, above Reeder Reservoir. This fuel reduction
zone also ties into a major U.S. Forest Service shaded fuelbreak to the east.
Tactical Opportunity #5
The vegetated slopes in Lithia Park east of Ashland Creek represent the single largest intrusion of
wildland vegetation into the City of Ashland. As a result, reducing wildfire potential through wildfire
management activities is a priority, as described in Management Priority #5. At the top ofthese
westerly aspects, significant vegetation manipulation and fuel reduction has recently been
accomplished both above and below Glenview St., extending upslope to the major ridgeline along
Ridge and Terrace Streets (see Picture #33). These fuel reduction activities, coupled with good access
for firefighting equipment, provide a critical tactical opportunity for wildfire suppression in the event
of a developing fire in the wildland portions of Lithia Park. Hopefully, this recent work will prevent
wildfire from spreading over the ridge and into the major urban/suburban portions of Ashland to the
east.
Tactical Opportunity #6
Management Priority #9 described needed vegetation management to achieve wildfire management
objectives in the Roca Canyon occluded interface. This work would "tie in" to existing areas of
reduced fuels largely represented by pasturelands/grasslands in two units, A14 and A15. The
alignment of these units perpendicular to upvalley air flow in the Bear Creek Valley could be
particularly important in any fire advancing easterly/southeasterly. Stopping developing fire in this
location could be particularly important given the high density of structures in the vicinity and the
large adjacent acreages of vegetation with high to extreme fire hazard ratings. Maintaining irrigated
pasture in these units would even further enhance the area's effectiveness as a fuel reduction zone and
potential utilization in a wildfire event.
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Tactical Opportunity #7
A major ridgeline fuelbreak has been implemented an Ashland Parks land in Siskiyou Mountain Park
(see Picture #34). This fuelbreak has been created in the hope of compartmentalizing wildfire to stay
within a single watershed, rather than crossing over from the Roca Creek watershed into. the
Hamiltan Creek watershed as accurred in the 1973 Hillview Fire. Effectiveness af these types of
fuelbreaks are largely dependent on the quality of work done in the fuelbreak (i.e. size, current
conditian ofthe vegetation, when it was last treated, etc.), the behavior of the fire when it reaches the
fuelbreak, and the availability of suppression activities. There are certainly many wildfire situations
in which this fuelbreak would not suffice to stop advancing wildfire. Hawever, it daes pravide a
significant opportunity with which to concentrate suppression activities, mast likely applicatian of
aerial retardant. Vehicle access would not be available to. this fuelbreak.
Tactical Opportunity #8
Tactical Opportunity #8 is a large area in the headwaters of the Roca Creek watershed on lands
managed by Ashland City Parks and Recreatian. The land was part of a purchase by the City
following a timber sale in the early 1990s. Since that time, a considerable amount of fuel reduction
work (thinning, brushing, grubbing, piling and burning, etc.) Has been completed. Although the
generally steep nature of the area reduces its effectiveness as a fuel reduction zone, the work
completed has created a large area of generally reduced fuels that will likely reduce fire intensity and
rate-of-spread in a wildfire event, increasing the likelihaod that it can be stapped prior to. entering the
Ashland Creek watershed. Ongoing work is needed in this area to. imprave its effectiveness as a fuel
reduction zone/tactical opportunity. Its lacatian adjacent ather majar fuel reduction zones (Tactical
Oppartunities 7 and 9, as well as on adjacent U.S. Forest Service land-both current and planned)
contributes to a much larger and subsequently more effective fuel reduction zone.
Tactical Opportunity #9
Significant fuel reduction and wildfire management activities have been completed on the Bill and
Sara Epstein property in Section 22 in the upper end of the Hamilton Creek watershed. Work in both
conifer/hardwood stands and brushfields has significantly reduced the potential for developing high-
intensity wildfire. Excellent opportunities exist to prevent spread of wildfire into the Ashland Creek
Watershed, particularly if suppressian farces and activities are available. Additianal wark in the Roca
Canyon watershed on Ashland Parks and Recreation land to the north (Tactical Opportunity #8) has
also improved the size of the fuel reduction zone, making it that much more likely to be effective in a
wildfire. Access to the upper end of Tactical Opportunity #9 is available from Ashland Loop Road, as
well as from various forest management roads on the Epstein property. This large fuel reduction
zone, created by active management activities on two larger ownerships, serve as an excellent model
for wildfire management strategies that have greatly increased the likelihood that wildfire could be
prevented from moving into the Ashland Creek Watershed from the adjacent Hamiltan Creek and
Roca Canyan watersheds. Maintaining the effectiveness and patential utilization of Tactical
Opportunity #9 will require additional work in the near future.
Tactical Opportunity #10
A large area of reduced fuels is located between Tolman Creek Road and Hamiltan Creek in the
southeast comer of the A WUI. This area includes old ranchlands/grasslands, managed aak woadlarlds
and/or those with very low fuellevels-quarries, abandoned orchards, and a recently managed
plantation that has been precommercially thinned, pruned, piled, and burned. This area is an excellent
example of reduced fuels of various types over a large area, providing an excellent tactical
opportunity far suppression in a wildfire event. Access is good throughout and topography is gentle,
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combining to provide a good level of protection from wildfire for the major suburban area
immediately to the north (Greenmeadows Subdivision).
Tactical Opportunity #11
Similar to Tactical Opportunity #7, a northerly/northeasterly descending ridgeline fuelbreak system
has been installed along the easterly boundary of the Hamilton Creek watershed. primarily on the Bill
and Sara Epstein property (see Picture #35). This fuelbreak is somewhat narrower in some places
than occurs in Tactical Opportunity #7. Brush removal and silvicultural thinning along this ridgeline
was mostly accomplished in the early 1990s, followed by conversion to conifers by planting. These
developing plantations are becoming less effective as fuelbreaks, although recent thinning to wide
spacing, pruning, and pile burning is helping to maintain effectiveness, while minimizing further
development of extremely wildfire-prone manzanita brushfields. The bottom northerly end of this
fuelbreak system ties into a large area ofreduced fuels (Tactical Opportunity #10) in old
ranchland/grassland. Access for utilizing suppression forces in this fuelbreak system is generally
good--either from Morninglight Estates at the bottom or Tolman Creek Road at the top. Maintenance
of this fuel reduction zone should become a management priority within the next several years,
allowing continued opportunities for containment and compartmentalization of a developing wildfire.
V. Conclusion
This report was developed in the hope of providing a general framework with which to analyze the
Ashland Wildland Urban Interface (A WUI), with a special emphasis on wildfire potentials and
subsequent opportunities to minimize its undesirable effects when it occurs. The report focused
primarily on fuels inventory and analysis of fuels and vegetation in the A WUI-the key factors
affecting wildfire behavior in the A WUI. Fully realizing that passive management (doing nothing),s
a choice that results in predictable and undesirable outcomes, specific options for management to
minimize wildfire behavior are prescribed in this report. These suggested "planned disturbances" are
designed to hopefully recreate stand structures and ecological processes that will help encourage the
type of more benign disturbance regimes typical of the pre-settlement era, as opposed to the more
infrequent, higher intensity disturbances being experienced today. These suggested management
activities should be tempered with retroactive looks at the effects of management activities and fuel
reduction to date on multi-resource values of various sites in the A WUI. Monitoring changes in the
future, both on the ground in individual units and on a landscape level, will also be an essential
element by which one can learn and adapt accordingly. The spatially explicit mapping in this report
of landscape units and vegetation types in the A WUI should allow the means of recording these
changes in wildfire potential over time and space, as well as offering a way for all interested parties
to visually comprehend the larger scale problems and opportunities. Engaging the citizens of
Ashland, particularly those with lands in the A WUI, is critical to the successful implementation of
acceptable wildfire reduction strategies. Given these realities, it should be clear that this report is
merely a start, and it is hoped that it facilitates a more aggressive approach to the protection and
promotion of the multiple values threatened by high intensity, large scale wildfire in the A WUI and
adjacent lands.
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Vegetation Management Conference, Redding, CA.
Perry, D. A. 1988. "Landscape Pattern and Forest Pests." The Northwest Environmental
Journal, 4: 213-228.
Perry, D. A. 1995. "Landscapes, Humans and Other System-level Considerations: A
Discourse on Ecstasy and Laundry." In: Proceedings of Ecosystem Management in
Western Interior Forests, May 3-5, 1994. Spokane, W A.
Skinner, C. N. 2002. Personal communication.
Taylor, A. H., & C. N. Skinner. 1998. "Fire History and Landscape Dynamics in a Late-
Successional Reserve, Klamath Mountains, California, USA." Forest Ecology and
Management, 111,285-301.
U. S. Dept. of Agriculture, Forest Service, Rogue River and Siskiyou National Forests.,
Pacific Northwest Research Station, and U.S. Department ofInterior, Bureau of Land
Management, Medford District. 1994. Applegate Adaptive IV1anagement Area Ecosystem
Health Assessment. Medford, OR.
USDA Soil Conservation Service. 1993. Soil Series of Jackson County Area.
Van Wagtendonk, J. W. 1996. "Use of a Deterministic Fire Growth Model to Test Fuel
Treatments." In: Sierra Nevada Ecosystem Project: Final Report to Congress, Vol. II,
Chap. 43. Davis: University of California, Centers for Water and Wildland Resources.
Weatherspoon, C. P. 1996. "Firesilviculture Relationships in Sierra Forests." In: Sierra
Nevada Ecosystem Project: Final Report to Congress, Vol. II, Chap. 44. Davis:
University of California, Centers for Water and Wildland Resources.
Weatherspoon, C. P., and C. N. Skinner. 1996. "Landscape Level Strategies for Forest
Fuel Management." In: Sierra Nevada Ecosystem Project: Final Report to Congress,
Vol. II, Chap. 44. Davis: University of California, Centers for Water and Wildland
Resources.
Glossary
Age class: A classification of trees of a certain range of ages.
Aspect: The direction in which any piece of land faces.
Basal area: The cross-sectional area of tree boles in a forested area as measured at dbh.
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Board foot: A unit of measurement represented by a board one foot long, one foot wide,
and one inch thick. Also, a standard way of measuring volume of standing trees, logs, or
lumber, usually expressed in thousand board feet, or mbf.
Bole: The main stem or trunk of a tree.
Canopy: The relatively continuous cover of crowns of trees.
Coarse woody debris: Boles of trees that have fallen or been cut and area laying on the
forest floor; usually refers to larger diameter material.
Competing vegetation: Any vegetation that competes with a preferred tree or seedlings
for site resources.
Crown fire: Fire that advances through the tops of trees.
Defensible fuel reduction zones: Areas of modified and reduced fuels that extend beyond
fuel breaks to include a larger area of decreased fuels. These would include managed
stands with reduced amounts, continuities, and/or distributions of fuels that would
provide additional zones of opportunity for controlling wildfire.
Density management: Management practices implemented to alter the density of trees in
a forest.
Diameter at breast height (dbh): The diameter of any tree at 4.5 feet above ground level.
Down, dead woody fuels: Dead twigs, branches, stems, and boles of trees and shrugs that
have fallen and lie on or near the ground.
Fire hazard: The kind, volume, condition, arrangement, and location of fuels and
vegetation that creates an increased threat of ignition, rate of spread, and resistance to
control of wildfire.
Fire intensity: The energy release rate per unit length of fireline; can be.related to flame
length.
Fire risk: The chance of various ignition sources, either lightning or human-caused,
causing a fire.
Fire season: The period of time, usually during the summer and fall, when there are drier
conditions and higher temperatures, and restrictions and rules designed to minimize
forest fire risks are put into effect.
Fire severity: Measures the effect of fire on an ecosystem, especially the effect on plants.
Fires are commonly classed as low, medium, and high.
Fire weather conditions: The state of the atmosphere within 5 to 10 miles of the earth's
surface indicated by measures of temperature, pressure, wind speed, wind direction,
humidity, visibility, clouds, and precipitation. The potential for fire weather conditions to
influence fire behavior is generally described in terms of low to extreme.
Fuel continuity: A qualitative description of the distribution of fuel both horizontally and
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vertically. Continuous fuels readily support fire spread. The larger the fuel discontinuity,
the greater the fire intensity required for fire spread.
Fuelbreak: A strip of land in which vegetation has been manipulated such that fires
burning into one are more easily controlled.
Ladder fuels: Flammable vegetation that provides vertical continuity between the surface
fuels and tree crowns.
Landscape unit: An area of land with relatively consistent topography and vegetation.
Lop and scatter: A method of slash treatment in which slash is cut into smaller pieces so
that it lies closer to the ground to increase decomposition and perhaps spread out to
decrease fuel accumulations.
Merchantable timber: Trees large enough to be sold to a mill.
Monitoring: The process of initiating and collecting information over time to determine
if desired outcomes of planned management activities are being realized.
Mycorrhizae: Symbiotic associations between particular species of fungi and the roots of
vascular plants.
Overstory: The uppermost canopy layer in a stand.
Pre-commercial (or noncommercial) thinning: The cutting of non-merchantable trees to
improve forest conditions and/or help achieve specific objectives or values.
Prescribed burning: The professional application of fire to forest or range sites under
specific conditions of weather, fuel conditions, moisture, time of day, and season
resulting in a pre-designated fire intensity and rate-of-spread.
Release: A term used to indicate the increased growth that occurs in a tree or stand of
trees following stand density reduction.
Restoration: The process of aiding the recovery of ecological integrity on a degraded site
or landscape.
Riparian area: A geographic area containing an aquatic component and adjacent upland
areas.
Thinning from below: The cutting of non-dominant trees in a stand, usually in order to
give more site resources to the dominant trees or to reduce ladder fuels.
Site productivity: The capacity of an area of land to produce biomass.
Slash: Tree tops, branches, bark, and other typically non-merchantable debris left after
forest management activities.
Snag: A standing dead tree
Species composition: The variety of species in any particular vegetation type.
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Stand: A grouping of trees in a forest of similar conditions that separate it from trees in
other adjacent areas.
Stand density: A quantitative description of the number and size of trees in a stand.
Stocking level: The number of trees in any given area.
Succession: The process through which vegetation develops over time as one community
of plants replaces another; often described in terms of stages or seres.
Surface fire: A fire that burns fuels such as downed wood, litter, shrubs, and small trees
which are near the ground.
Swamper burning: A method of burning in which slash is thrown onto a burning pile.
Tree vigor: A measure, either subjective or quantitative, of the relative health of an
individual tree.
Understory: The vegetation layer between the canopy and the forest floor, including
forbs, shrubs, smaller trees, and other low-lying vegetation.
Uneven-age management: Management of forests that encourages different age classes
within a stand, involving both the retention of older age classes and the encouragement
of new trees.
Wildland/urban interface: A geographic area in which the urban and/or suburban setting
is juxtaposed and transitionally grades into the wildland environment.
List of Scientific and Common Names Used in This Report
Conifers:
Douglas-fir - Pseudotsuga menziesii
Incense cedar - Calocedrus decurrens
Ponderosa pine - Pinus ponderosa
Sugar pine - Pinus lambertiani
Hardwoods:
Bigleaf maple - Acer macrophyllum
Black cottonwood - Populus trichocarpa
California black oak - Quercus kelloggi
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Mountain mahogany - Cercocarpus betuloides
Oregon ash - Fraxinus latifolia
Oregon white oak - Quercus garryana
Pacific madrone - Arbutus menziesii
Red alder - Alnus rubra
Willow - Salix spp
Shrubs:
Deerbrush ceanothus - Ceanothus integerrimus
Dwarf Oregon grape - Berberis nervosa
Hairy honeysuckle - Lonicera hispidula
Mock orange - Philadelphus lewisii
Pacific ninebark - Physocarpus capitatus
Poison oak - Rhus diversiloba
Snowberry - Symphoricarpus mollis
Wedgeleaf cenaothus - Ceanothus cuneatus
Whiteleaf manzanita - Arctostaphylos viscida
Forbs:
Horsetail - Equisetum spp.
Sedges - Carex spp.
Rushes - Juncus spp.
Exotics:
English ivy - Hedera helix
Himalayan blackberry - Rubus discolor
Exotic, Noxious Plants in A WUI (partial list)
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Common Name
Latin Name
Himalayan blackberry
Dalmatian toadflax
St. John's wort
Scotch broom
poison hemlock
yellow starthistle
hedgehog dogtail
medusahead rye
Canada thistle
bull thistle
Rubus discoler
Linaria dalmatica
Hypericum perforatum
Cytisus scoparis
Conium maculatum
Centaurea solstitalis
Cynosurus echinatus
Taeniatherum caput-medusae
Cirsium arvense
Cirsium vulgare
Lychnis coronaria
Bromus diandrus
Centaurea maculosa
Hederahelix
Vinca minor
rose campIOn
ripgut brome
spotted knapweed
English ivy
periwinkle
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