HomeMy WebLinkAboutSilvicultural PrescriptionA Silvicultural Prescription for High Priority
Forest Management Areas
A Report Prepared for
The City of Ashland
by:
Marty Main
Small Woodland Services, Inc.
1305 Butte Falls Hwy
Eagle Point, OR 97524
February 2, 1996
Table of Contents
Introduction
Map
Physical Description of Main Area ..................................... 1
Vegetational Community Development Patterns
in the Lower Ashland Watershed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6
Silvicultural Planning-An Overview ................................... 15
Stand Management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 15
Reforestation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 22
Natural Regeneration .................................... 22
Artificial Regeneration ................................... 25
TiInber Harvest ...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .' 27
Fire Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 34
Planning for Biodiversity, Wildlife Habitat,
and Long-Term Site Productivity . . . . . . . . . . . . . . . . . . . . . . . . '.' . . . . . .. 40
Changes, in Resource Values from Choosing
a "No Action" Alternative .......................................... 44
Management Unit DescriptionsfPrescriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 48
Summary and Prioritization of Management Activities. . . . . . . . . . . . , . . . . . . . . .. 61
Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 64
City of Ashland/i
INTRODUCTION
Small Woodland SeIVices, Inc. was commissioned by the City of Ashland to develop
silvicultural prescriptions for an area prioritized for forest management activities in a previous
assessment by the same company ("A Preliminary Assessment of Forest and Resource
Management Priorities on City of Ashland Owned Lands," Small Woodland Services,
October, 1995). Preliminary meetings with Pam Barlow and Keith Woodley of the City of
AsWand suggested three primary objectives in the management of the above area as outlined
in the Preliminary Assessment:
1. Protection of watershed values and maintenance of water quality and quantity
for the City.
2. Maintenance and/or promotion of forest and ecosystem health.
3. Reduction in wildfire hazard and risk.
- The Forest Plan for City of Ashland Forest Lands completed in May, 1992 by R.I.
McCormick and Associates clearly spells out a general management for all the City-owned
forest lands. It also provides a foundation on which this report rests. The management
direction suggested in that plan is professional, sound, and fully deserves to be carefully
adhered to. This report offers little new direction, but rather a more intense, site specific
descriptions and analyses for one portion of the City ownership higWy prioritized for
management activity. Within the management area addressed by this report, it updates
management direction slightly, based on changes that have resulted in the three-plus years
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City of Ashland,lii
since the McConnick plan was developed.
The McConnick Plan, on page 3 of Chapter 1, states,
"In our iudgement. created disturbance that emulates natural ecological
processes must be reintroduced into the watersheds. If thiS does not occur,
there is a very high risk of catastrophic wildfIre and a rapid loss of old growth
and other age classes through insects and disease."
This report fully concurs with that assessment and add that three years of time without
"created disturbance" has substantiated and further aggravated the existing problems.
Mortality of overstory conifers and other associated changes from insects has continued, if
not escalated. Loss of overstory conifers ultimately contribute to soil instability as roots die
and lose strength, contributing to decreased soil stability with potential negative impacts upon
hydrologic realities in the watershed. Snag development, coupled with ongoing vegetative
growth and subsequent increases in fuel loading in the last three year, has even further
increased fIre hazard and the chance for catastrophic wildfrre. Reversing these trends of
declining stand vigor and subsequent increased likelihood of stand mortality from either
insects and/or wildfrre seems even more urgent than three years ago. Without a proactive
approach of implementing "created disturbance that emulates natural processes," catastrophic
wildfrre is clearly imperative, with a significant if not overwhehning decline of virtually all
of the values so clearly associated with City-owned forestlands. Obviously, this type of
wildftre could easily threaten significant portions of the City of Ashland itself.
This report makes recommendations for sound forest and resource management
activities that emulate natural ecological processes and are designed to hopefully reverse these
City of Ashlandfiii
negative trends within the designated management area. These are recommendations only,
and are not intended to offer immediate solutions to the complex silvicultural and forest
management problems that exist both on a landscape level and. within the designated
management area. Forest ecosystems operate on much longer time frames than most human
endeavors-and management activities designed to facilitate the above-stated objectives will
only be successful if measured over longer time frames and larger scales of reference.
Nonetheless, this report hopefully will provide the City of Ashland with enough information,
analysis, and delineation of options and costs with which to begin making sound management
decisions for the designated management area.
City of Ashland/ 1
PHYSICAL DESCRIPTION OF MANAGEMENT AREA
A. General Description
The management area addressed in this report is located in the lower, most
northerly portion of the City of Ashland ownership within the Ashland
Watershed. It is located primarily in a block comprising the southwest quarter
and the bottom quarter of the northwest quarter of Section 16 of Township 39
South, Range 1 East. This management area is referred to as Parcels 4 and 5
(excluding the area west of the main canyon road) in the Ashland Forest Plan
prepared by R. J. McCormick and Associates in May, 1992.
Approximately 105.
Access to the management area is limited. The main haul road on the east
side of Ashland Creek fonns most of the westerly boundary of the manage-
ment area. Access to the northwest comer of the management is provided by
an access road to an abandoned granite quarry. Ashland Loop Road provides
limited access through the very northeastern comer of the management area.
The large bulk of the management area is steep and has no vehicle access.
Topography: The management area is dominated by two primary topographical features:
(1) a major ridgeline at 3,000 to 3,100 feet in the northeastern comer of the
management area; and (2) the canyon bottom of Ashland Creek, at an
elevation of 2,200 to 2,300 feet. The majority of the management area is
located between these two topographical features. Topographical draws that
Location:
Acres:
Access:
run water only during major storm events drain southwesterly to westerly from
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City of Ashlandj3
for sheet and gully erosion, as well as mass soil movements. Fortunately, rain
on snow events are rare in the management area, but continued heavy rainfall
in winter or intense events such as swnmer thunderstorms can cause consider-
able erosion, particularly on these steeper slopes. Road construction should be
avoided whenever possible, as roads are primary sources of erosion and
subsequent sediment inputs into the aquatic ecosystem. Maintenance and/or
restoration of existing roads or other non-vegetated spots (i.e., quarries) is of
high priority in these soils. The USDA Natural Conservation SeIVice has
mapped this entire area (see appendix) and has delineated two primary soil
series or types: Tallowbox gravelly sandy loams on the steeper slopes and
Sheftlein loams on the gentler slopes, primarily on the major ridgetop location.
Vegetation: Vegetation in the management area is dominated by the Douglas-fir se-
ries-mixed conifer-hardwood woodlands with scattered brushfields on more
southerly aspects. On more northerly aspects, the vegetation is dominated by
stands of dense Douglas-fir, with lesser amounts of Pacific madrone. Forest
vegetation on more southerly aspects has greater species diversity, with
Douglas-fIT, Ponderosa pine, Pacific madrone, and California black oak
dominating, but also including less common sugar pine and incense cedar.
Whiteleaf manzanita dominates scattered brushflelds on these more southerly
aspects, often forming dense, impenetrable stands and/or being found in
association with other hardwoods (pacific madrone, California black oak) or
brush species (mountain mahogany, deerbrush ceanothus). Understory
City of Ashland,/2
the ridgeIine down into Ashland Creek. Associated ridges are located between
each of these topographical drawst creating opposing northerly/northwesterly
and southerly/southwesterly aspects. A small portion of the management area
(approximately 10 acres) is located on more easterly-northeasterly aspects on
the east side of the major ridgeline. The riparian habitat along Ashland Creek
itself is an important management area, but is not included in the descriptions
and analyses in this report.
Precipitation: Annual precipitation has historically averaged 25 to 30 inches, although that
amount has certainly decreased during the last decade of drought years
(typically down to 50 to 75 percent of annual averages). Very little of that
total falls as snow at the lower elevations typical of the management area.
Perhaps more importantly, however, is the highly seasonal nature of that
precipitation, with less than 15 percent of that total occurring during the
seasonally dry period from May through September. This has important
ecological implications for vegetation establishment and growth, and ultimately
forest management decision-making.
Soils: Soils in the management area are derived from intrusive igneous rocks formed
during the Jurassic Age, 145 to 164 million years ago. The resulting soils
were formed largely from colluvium derived from these granitic parent
materials. The coarse textured soils are moderately deep and well to
excessively drained. The lack of cohesiveness allows these soils to be easily
moved, particularly during major storm events when a high likelihood exists
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History:
City of Ashland/4
vegetation typically includes tall Oregon grape, poison oak, snowberry,
oceanspray, honeysuckle, and various grasses and broadleaved herbs.
The degree of Native American use of the management area is unknown,
although extensive use was probably unlikely. However, it is likely that
Native American burning in the Rogue Valley commonly "escaped" to the
forested regions such as in the management area, thereby affecting develop-
ment of forest vegetation. The presence of several older age classes scattered
around the management area (at least three) in the range of 125 to 200 years
suggest repeated disturbance in that era, most likely related to fIre events,
either caused by lightning or indigenous peoples. Early Euro-American use of
the area was also probably minimal. The Ashland Forest Plan (McConnick
and Associates, 1992) indicates the establishment of the original Ashland
Forest Reserve in 1893, which mayor may not have included the management
area but undoubtedly affected management and disturbance possibilities for the
area. Large wildfIres occurred in the management area in 1901 and 1910. The
1901 fire appears to have been rather severe, as it appears that only scattered
older trees survived that fIre. By 1902, the early beginnings of fIre suppres-
sion and exclusion were instituted in the Ashland Watershed area. The 1910
fIre burned quite vigorously and completely on northerly aspects (probably due
to the fact that the 9-year-old vegetation that developed after the 1901 fIre was
primarily dense thickets of conifers, hardwoods, and/or brush-an extremely
fue-prone vegetation type), but appears to have varied considerably in intensity
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City of AshIand/5
on more southerly aspects. A ground-based logging (probably horses) of
scattered timber, particularly on more southerly aspects, was completed in the .
late 1930s. A helicopter logging was completed in 1990, largely removing
scattered pockets of dead, dying, and (perhaps) other mature overstory timber
throughout the management area.
City of Ashland/6
VEGETATIONAL COMMUNITY DEVELOPMENT PATTERNS
IN THE LOWER ASHLAND WATERSHED
The successful management of a vegetation type (Le., timber, grass, etc.) designed to
achieve any particular set of objectives ultimately depends on an understanding of how that
vegetation develops and why it exists in the given situation. This is particularly important
in many places in southern Oregon because the vegetation has moved beyond the range of
historic conditions and into a type that is under considerable stress.
Forest vegetation composition is continually and significantly determined by relatively
constant environmental variables. such as elevation, aspect, annual rainfall, soil type and
depth, and numerous other factors. Variations in these environmental variables can. in
themselves, produce differences in site conditions. In southern Oregon, 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 in most
of sO!lthern Oregon, and particularly at lower elevations such as the management area upon
whicl1 this report focuses.
Aspect is an important environmental variable because greater amounts of solar
radiation on southerly aspects during long, dry sununer months limits moisture availability
much more so than on northerly aspects (with easterly and westerly slopes intermediate).
Obvious changes in vegetation occur in the management area on opposing southerly and
northerly aspects. Douglas-fir heavily dominates the more northerly aspects, while much
more diverse species compositions occupy more southerly aspects, including not only
Douglas-fIr but also Ponderosa and sugar pine, mixed hardwoods, and abundant brush species,
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City of Ashland.{7
all species tolerant of harsh, droughty site conditions.
The amount and seasonality of precipitation is also obviously important for vegetation
establishment and survival. In particular, the lack of precipitation during summer months
greatly affects the type, quantity, and diversity of vegetation that can survive and prosper.
Variations in soil properties are particularly important determinants of vegetation on
any given site. Highly productive forest soils in southern Oregon usually have the following
characteristics.
. . More than 36 inches deep, with a well developed layer of topsoil
. Medium-textured loams, with little or no heavy clays
. Well drained topsoil, with moisture holding subsoil
. Less than 35 percent coarse rock fragments
. No hardpans or impermeable layers near the soil surface
These types of productive soils are particularly capable of storing greater amounts of
water, the critical limiting factor to vegetation survival and growth in southern Oregon.
Shallow soils of 24 inches or less and/or containing high percentages of rock fragments are
only capable of supporting plants with specific adaptations allowing for survival at low
moisture availabilities. In addition, 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
City of Ashland/8
soils, it cannot compete favorably with other trees that prefer these locations (conifers, Pacific
madrone, etc.) and thus is seldom found.
Unlike the fIrst two environmental variables (aspect, precipitation), however, soil types
and particularly depths, although fairly constant over time, can be quite variable even within
small areas in southern Oregon. This wide variety of soils in southern Oregon accounts in
large part for the wide diversity of vegetation types, even within small areas.
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 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.
Strictly looking at environmental site conditions, however, ahnost never fully explains
why a given vegetational composition and structure exists on a site. Traditional theory in
vegetational community development has suggested that vegetation moves through a relatively
predictable series of steps (called plant succession) until an old growth, climax forest is
reached. Carried to logical conclusion, this theory would suggest that, without human
influence or other disturbance mechanisms, the forests of the Pacific Northwest would have
been ahnost solely stable, old growth forests prior to the European settling of the area.
However, extensive research in recent years suggests a slightly different analysis. On
the contrary, disturbance of various kinds had consistent and often profound impacts upon
vegetation, producing a variety of vegetational structures across a landscape. These
City of AshlandJ9
disturbances would include wind storms; ice stonns; droughts and related mortality; insect and
disease outbreaks; landslides; flooding and/or erosion from peak storm events; and, most
importantly, fIre (ignited by either lightning and/or Native Americans). Many of these
disturbance events were synergistic-that is, they worked together to kill existing plants and
return sites to the earlier stages of succession.
These two categories of site condition detenninants (environmental site conditions,
natural disturbance history), then, provide much of the explanation for existing condition of
vegetation on a site if they are analyzed correctly. However, a third major detenmnant may
be the most important of all-that of management history, particularly within the last 100
years.
Typical management history impacts include many that are commonly known-\vild-
fIre, mining, logging, grazing, off-road vehicle use, and various other construction and
recreational activities. Perhaps the impact with the greatest influence is one of the least
known and understood-that of fIre suppression and exclusion.
Prior to the European settling of southern Oregon, the primary natural disturbance
mechanism in southern Oregon forest and range ecosystems was frequent, low intensity
groundfrre. These fIres, ignited by Native Americans and/or lightning, ranged in frequency
anywhere from 10 to 50 years for anyone site in southern Oregon, depending on elevation,
aspect, fuel and vegetation density, climate, and other frre-related variables. Fire frequencies
prior to the disruption of natural rue cycles were estimated at 8 to 10 years in the interior
valley zone and 15 to 20 years in the mixed conifer zone, both types that exist in the
management area (Ashland Forest Plan, 1992). Ignited any time during the seasonally hot
e___ __--...-.~___.__.,_~
City of Ashland,! 10
and dry rrre season and often creeping through the woods all summer long, these fIres seldom
flared up into wildfrres as we know today-primarily because they removed fuel accumula-
tiOIlS. both dead and green, on a regular basis rather than allowing it to increase into the
proportions we have today.
Since the turn of the century, however. the conscious choice was made to extinguish
all rrres quickly and thoroughly. This may have been due, at least in part, in response to
increasing numbers of wildfrres that were occurring as a result of the elimination of Nati ve
American burning, increased downed fuel and slash from increasing lumbering and other
developmental activities, and purposeful creation of wildfrre by those who desired more open
landscapes (miners) and/or the earlier stages of succession (ranchers, for native pastures).
This hurrian-induced impact (elimination of frequent low intensity rrre) upon the forest
ecosystems of southern Oregon (and most of the western U.S.) has been particularly important
in terms of forest management because frequent, creeping, low-intensity ground Ere
accomplished the following forest management functions:
1. Periodically cleaned up the woods of dead and downed material as well as
reducing the heavy over-stocking of brush and small conifers we see today. The
result was greatly reduced fuel loadings and subsequent decreased likelihood,
extent, and intensity of wildftre.
2. Periodically reduced stocking levels in the woods, leaving the larger (and usually
more vigorous) dominant trees (with more protective bark) and releasing them
from competition of the smaller saplings, poles, and brush killed in these light
rrres. Some smaller seedlings and saplings always escaped creeping, low-intensity
groundfrre that typically burns in a mosaic fashion. The dense, overstocked, and
highly suppressed stands we have today were much less likely to occur when Ere
burned frequently at low intensities.
3. By maintaining a healthier, less crowded and more vigorous stand AND by
reducing available habitat (downed slash), forest conditions were far less desirable
...~
City of Ashland/II
for significant increases of destructive insects. Fire, and smoke, also played a
critical role in the control of many deleterious forest diseases that have subse-
quently increased dramatically.
4. Frequent light fIre varied considerably in intensity as it crept through the woods.
In response to this highly diverse and ever-changing impact, a greater variation in
vegetation species, ages, and structures was maintained. This maintenance of high
degrees of biodiversity is an important feature of healthy, resilient forest
ecosystems. In the absence of rue, species composition has significantly changed,
with shade tolerant species favored.
5. Frequent, low intensity fue maintained more open stand conditions that encouraged
development and maintenance of larger, shade-intolerant species, most notably
Ponderosa pine. In the absence of fue, species composition has significantly
changed, with shade tolerant species favored. Throughout the Western United
States, these now overstocked shade tolerant species have been severely impacted
by numerous forest insects and diseases. In addition, in the absence of frequent
fue, stump-sprouting hardwoods and brush species that typically grow quite slowly
when initiated by seed, have become much more common, further impacting
development and even survival of conifers.
6. Periodic ground fue provided an excellent seedbed (ash) for natural regeneration
of conifers. In the absence of fue, duff accumulations on the forest floor often are
too great to allow for establishment of many coniferous seedlings. most notably the
pmes.
7. Fire played a critical role in nutrient recycling, particularly in drier, moisture-
limiting climates where decomposition can be very slow. Frequent, low-intensity
fue recycled nutrients "locked-up" in above ground fuel (both dead and green) and
provided a fresh flush of vigorous growth not only on conifers, but of all
vegetation 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 dramatically increased nutrient loss given the greater
likelihood of stand destruction through wildfue and/or excessive harvesting.
8. Frequent fue is suspected to have maintained a lower level of above-ground
biomass than exists today after 60 to 80 years or more of fue exclusion. The
increased transpirational demands of this additional vegetation has decreased the
amount 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 fue from occurring in the
City of Ashland! 12
frre-prone forests of southern Oregon, particularly given ever-increasing fuel levels. It is
more appropriate to think about managing the intensity of the fIre, rather than the occurrence
of frre-and such is certainly the case in this management area. The type of large-scale
wildfire event typical today was rare and certainly of much smaller acreages and intensities
prior to the era of fire exclusion.
Once initiated through fIre exclusion practices, however, the pattern of infrequent but
intense wildfrre (as opposed to frequent fIre of low intensity) tends to reinforce itself as the
densebrushfields and stands of thick, juvenile conifers and stump-sprouting hardwoods (the
earlier stages of succession) are much more prone to wildfrre of larger scales and higher
intensities. These vegetation conditions are common throughout the management area.
Houses built up into these vegetation conditions (particularly along the northern property line of the
managffilent area) are at extreme risk in the event of wildfire.
It is very likely that other as-yet undetected ecological functions were perfonned by
peri~c low-intensity fIre. However, in its absence, we currently have stands (even some
stands that have never been harvested) throughout southern Oregon that are tremendously
over-stocked, with a high proportion of individual trees and stands under significant stress.
These stand conditions provide ideal conditions for rapid escalation of bark beetle
populations, as bark beetles can sense and generally attack trees under severe cumulati ve
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. Fortunately,
the negative effects of disease (very little dwarfmistletoe, root rots, or other diseases were
found in the management area), logging damage and soil compaction were minimal in the
City of Ashland! 13
management area.
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), with a different cadre of bark beetles
restricted to their preferred tree species. Flat headed borers (Melanophila drummondi) and
Douglas-fir beetles (Dendroctonus pseudotsuga) are causing the extensive mortality of
Douglas-fIr throughout the management area and immediate environs. An entirely different
cadre of bark beetles, primarily western pine beetle (Dendroctonus brevicomis), mountain pine
beetle (Dendroctonus ponderosa), and pine engraver beetles (Ips pini) are the primary
destroyers of Ponderosa pine. When populations of these cadres of bark beetles explode,
even healthy trees can be overcome and mass mortality can occur, such as occurred in Lithia
Park several years ago.
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 management area because this size class of Douglas-fir is the
size of the preferred dominant trees that represent the future. Many of the preferred trees
have been, and are being, killed by bark beetles. leaving only suppressed, poor quality
understory trees. The opportunity for improving stand conditions through silvicultural
activities is much reduced in this situation, and often not possible at all if mortality is
significant enough-in essence. leaving no available silvicultural technique for trying to
~~_H''''''.__'____'''"'
City of Ashland/14
healthy stand on a site. Succeeding and increasing populations of Douglas-fir beetles in
conjunction with flatheaded borers, then, can destroy the remainder of the Douglas-fir in the
stand, such as occurred several years ago in Lithia Park, where virtually all of the Douglas-fir
were destroyed.
Currently, all stages of this process can be found within the management area.
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.
Preventing or reducing insect damage, then, primarily involves preventing individual
tree stress, or in other words maintaining a healthy stand. Natural, creeping, low intensity
fires helped accomplish this by maintaining reduced stand densities. Manual thinning to
reduce stand densities and improve overall stand health and vigor simulates these thinning
effects of low intensity fire.
') Small diameter Douglas-fir slash created in these activities is not preferred habitat for
Douglas-fir bark beetles, and thus is not a potential breeding site. However, the beetles that
attack Ponderosa pine can increase their populations ~tically in green Ponderosa pine
slash cut during the months of January through June or July. As mariy as 3 to 4 generations
of pine engraver beetles can occur in one season in southern Oregon. For this reason,
thinning and release treatments in Ponderosa pine forests should be restricted to autumn.and
early winter, unless the green pine slash can be immediately disposed of.
The failure to address the rapid population explosions of these various bark beetles
is to insure the increasing demise of the existing stands of conifers, as well as significantly
contributing to potential severe wildtrre behavior.
..
City of Ashland! 15
SILVICULTURAL PLANNING-AN OVERVIEW
Ideally, any particular forest or woodland has been and is being managed within a
specific, well thought-out silvicultural plan designed to match the site, its potentials for forest
development, and the desires of the owner. In essence, silviculture is the professional process
of trying to modify forest vegetation in such a way as to meet the objectives of the forest
landowner. Unfortunately, it appears that very little, if any, silvicultural planning has
occurred on City of Ashland owned lands in the Ashland Watershed. Certainly this has been
the case on the portion of those lands addressed in this report. In fact, it appears that the
only activity in the last 50 years in the management area has been a mortality/sanitation
salvage helicopter sale conducted in 1990. Apparently, this was a rather sudden operation
with little silvicultural planning-primarily an attempt to quickly retrieve volume in order to
trade for retaining additional volume on a more visible parcel to the south.
In sound silvicultural planning, responsibility for development of the stand and
associated vegetation must exist from stand initiation and continue through the life of the
stand. Most of the management area is currently dominated by existing stands of mixed
conifers and hardwoods. The primary silvicultural emphasis, then, should be on stand
management, although stand initiation through planned reforestation activities may be
necessary on understocked or unstocked portions of the management area (i.e., brushfields,
patches of insect-killed conifer mortality, etc.).
Stand Manaeement
Stand management generally refers to the process of planning for a development of
,....-_...~.,..._.
City of AshlandJ16
stands of desired species, ages, sizes, and structures, to achieve a specific set of objectives.
As a generalization, stand management planning that attempts to create stand conditions that
reflect the range of historic conditions is highly desirable. These types of stands will be
better able to respond to the natural processes and functions that occur in healthy forest
conditions. It is suspected that the conditions of the existing stands in the management area
addressed by this report are probably well outside the range of historic conditions and, thus,
.""
more susceptible to considerable damage from otherwise natural processes such as fIre,
insectS, disease, and others.
In sound silvicultural planning, stands are managed through periodic removals of
growing stock, much as fire did prior to Euro-Arnerican settlement. These removals can be
either commercial or pre~ommercial in nature. In this relatively classical description of
forest management, commercial harvesting can be utilized to produce even-aged stands using
clearcut, shelterwood, or seed-tree harvest methods; or uneven aged stands using group
selec~on, single-tree selection, or other continuous canopy methods. Unexpected mortality
is re~eved in mortality salvage timber sales, while sanitation salvage sales remove diseased,
deformed, defective, or otherwise poor quality trees. Following harvest, regeneration (if
needed) is planned for using either natural seedfall or planting of conifers, or a combination
of the two. Trees destroyed by wildftre, disease, insects, windthrow, or other disturbance
events are usually harvested, if possible, and the areas inmiediately replanted with conifers.
Developing stands are carefully managed to assure optimal stocking levels of desired species,
as well as to attain other multiple resource objectives. Pre~ommercial thinning and release
treatments are used to accomplish these objectives in younger stands. In stands with
City of Ashland! 17
merchantable size classes, intermediate harvests, such as commercial thins, maintain
appropriate stand densities to meet management objectives.
In the management area addressed by this report, the second growth stands are
considerably overdense and could obviously benefit from thinning and release activities
designed to reduce stand densities. These "stand improvement" type of entries, either
commercial and/or pre-commercial in nature, can accomplish seven important objectives:
1. 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.
2. Individual trees, under more optimal densities and subsequently of greater health
and vigor, \J.rill be better prepared to withstand attacks from deleterious insects
or diseases.
3. By thinning and removing a portion of the above-ground fuel, both the
likelihood of ignition, 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.
4. Volume growth will be redistributed onto fewer, healthier, more valuable trees.
Growth rates will improve dramatically on these released trees. Larger trees
will be developed much sooner subsequently decreasing logging costs (less trees
to make the same volume) and increasing in value (larger logs are often of
higher, more valuable grades).
5. Thinning can upgrade the overall condition of the stand by selectively removing
trees that are deformed, diseased, defective, infected with insects, and/or heavily
suppressed.
6. A current thinning will make it possible to utilize or market trees that otherwise
might be outcompeted and killed in the natural progression of the stand.
7. Thinning can shift stands to more favorable or desirable species compositions.
Several different methods of thinning are available, dependent on objectives. The
preferential technique in this area whenever possible is a "low thinning" or "thinning from
.. ._,.,._.-~~~'-,..,.- ,--.,."......~.. " ,.-....,-~,. -"--"
City of Ashland/I 8
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. This generalized approach must be tailored to fit individualized stands,
however, and may not be appropriate in which overstory conifers have died or are in poor
condition.
Coniferous leave trees 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
have at least one-third of their total height occupied by a healthy crown (foliage). In this
management area, leave trees should usually be the largest trees of any particular age class,
as they are the most likely to exhibit the above traits and have superior growth rates. Having
been dominant for the largest time, these larger trees will release more quickly than other less
dominant trees, adding more volume in a shorter time. In stand improvement thinnings,
larger trees should only be removed if they are obviously dying, heavily diseased, deformed,
or insect-infested, or amidst an overstocking of other better, larger trees.
The pines, Ponderosa and (rarely) sugar, should generally be the preferred "leave"
trees throughout the management area, with the possible exception of the more northerly
aspects in the western parcel, where Douglas-fir would be equally preferred and currently
dominates. The pines tend to outperform the other native conifers on harsher, more southerly
aspects in the management area. Sugar pine is a particularly appropriate leave tree due to its
scarcity in this area. It is particularly sensitive to overcompetition, however, and thus
requires greater attention to reduction of stand densities in its vicinity. Prior to Euro-
American settling of the area and the advent of frre exclusion, native stands contained a
-,. '-'--'~-.'-'----'-''''''-'~'''------'~--,-"~,~--,-,-""",,,-,-'_.-'-~----""'--'
III
City of Ashland/19
greater percentage of sugar pille and particularly Ponderosa pille, and current Sp~'Cl~S
composit jOllS may often be outside the range of historic conditions. Ponderosa pine, however,
is shade intolerant and only docs well in full sunlight. More shade tolerant conifers such as
Douglas-fir and incense ct'dar are preferred over Ponderosa pine for understory leave trees,
as Ponderosa pine in shade is usually tall, spindly, and with poorly developed crO\vns. \Vh~n
thinning in the mixed coniferous forests in the management area, however, any of the existing
species are appropriate leave trees, and overall tree vigor and condition L'i usually more
important than individual tree species.
Hardwood" should generally receive the lowest priority III terms of leave trees,
particularly if they are becoming overtopped by healthy conifers. They can offer significant
growth and competition for prderred leave trees, subsequently causing reduced gro\\1h and
vigor and increasing susceptibility to disease and insects. As previously mentioned, the
increasing number of hardwoods in our native forests is largely a stand development response
to the lack of fire and is probably outside the range of historic conditions in many stands.
Hardwoods are now in a uniquely advantageous position to assert increasing levels of
dominance, particularly in a world of infrequent, high intensity fire where their ability to
stump sprout offers significant advantages over conifers.
If hardwoods are not significantly competing with preferred conifers, however, they
can be left in existing stami" and managed as well. Hardwoods will respond to thinning and
density control just as conifers do; in fact, local research has suggested they respond even
faster and more substantially to density control than do conifers. They may also be retained
for their aesthetic appeal and/or left to prevent damage, shock, or sunburn to the upcoming
City of AshlalllV~U
sa pI ings.
Hardwoods can also be excellent cash flow crops as they grow quite rapidly initially
and subsequently can have a much shoner rotation age. In mixed stands, they may contribute
to greater overall volume growth than in single species stands. Too, the future markd kn
hardwoods is largely undetennined but has certainly been improving in recent years. Larger,
straight-boled individuals free from rot may be particularly valuable and can be prioritized
for retention in release treatments.
Hardwoods also perform numerous other ecological functions. They may perform
the role of a "nurse crop," ameliorating site conditions so that natural regeneration of more
shade tolerant conifers can occur. They are also important for maintaining diverse wildlife
populations and add to the overall vegetational diversity on the property. Some hardwoods
form important mycorrhizal associations with conifers and contribute to improved soil
physical, chemical, and biological properties. Hardwoods intermixed ill stands of conikrs are
also suspected to contribute to reduced wildfire intensity, particularly when compared to 3
uniform stand of young conifers. Thinning to promote hardwoods, although rare in the past,
may be appropriate forest management in the years to come.
Spacing between leave trees should be such that the remaining canopies are mostly
free to grow in all directions. Distance between coniferous leave trees can generally be'
detennined by taking the average diameter of any small stand in question and adding a figurl'
of 4 to 5 to determine the footage spacing between trees (this is known as the D+ mle). It
may take several thinnings to achieve this idealized goal, however, as overdense stands can
easily shock ami/or bend over from excessive thinning.
..
City of AsWand/21
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. Thinning by basal area allows one to easily
make adjustments in the field for differing diameter sizes (and ultimate 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.
Preferred stand density after thinning also depends on the goals and desires of the
landowner. If more rapid development of larger trees is desired, heavier thinnings are
suggested. If slower growth for tighter rings, higher log quality, and/or other wildlife or
aesthetic value is desired, lighter thinning may be preferred.
The ideals listed above generally apply to stands of a single species. Because of
differing environmental and physiological needs of trees of different species, greater stocking
levels can be left in multi-species stands than in stands of a single species. Too, a stand of
diverse species is less susceptible to devastating insect or disease outbreaks.
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.
In very intensive management styles, individual crop trees can be identified, retained,
"._._..~-,_..,_..~.-_.,."._~- -, ---_.....--.~
City of AshIand,122
and allowed to grow to greater sizes and qualities such that their full value can be realized.
This management style is often called individual tree selection and has been made particularly
more viable in recent years due to the rapidly increasing value of logs. Maintaining aesthetic,
wildlife, or other resource values important to many landowners can be more easily achieved
in this style of management. It does, however, require a greater intimacy with the property
on the part of the land mangers, and a subsequently increased investment in time, energy, and
knowledge.
C. Reforestation
Two categories of reforestation-natural and artificial-are available to forestland
owners. The forested stands in the management area are almost all currently fully stocked,
if not overstocked, and will require little reforestation in the near future (unless a wildfire or
heavy harvest removes a portion of these stands). However, understocked brushflelds and
pockets of insect-killed timber do currently exist within the management area and may need
reforestation. Understanding both methods of reforestation is necessary in order to select
optimal stand establishment strategies.
Natural Re2eneration
Natural regeneration IS a very effective form of reforestation, though often
underestimated and underutilized. Most natural regeneration has historically been an
unplanned event occurring naturally after fIre and/or harvest activities disturb sites (such as
was obviously the case in the fIrst 15 years of this century in the management area).
City of Ashland/23
However, if properly planned, it has several distinct advantages.
. It is free-or at most very inexpensive if limited site prep work is undertaken.
. Seedlings are site-specific and genetically adapted for survival and growth in a given site
through thousands of years of natural selection.
· Seedlings can develop natural root systems that are more extensive than newly-planted
nursery-bred seedlings, resulting in a more balanced seedling with a greater probability
for growth.
. Far greater numbers of seedlings per acre can develop-an important consideration,
particularly if damage from animals (such as gophers) is expected.
. Perhaps most importantly, it is simple and can achieve reforestation objectives without
requiring the critical degrees of timing and professionalism required from start to finish
in the process of artificial regeneration.
Given these significant advantages (particularly cost and ease of application), it is
surprising that it is not intentionally used more often today. Several disadvantages, however,
have prevented its wide acceptance:
· Its relative uncertainty of success in short time frames fails to assure rapid stand re-
establishment following intentional or unintentional stand operungs.
· Densities of seedlings established by natural regeneration are very unpredictable,
particularly for large operungs where seedling microsites have been significantly altered.
· It requires the preservation of residual, cone-producing trees that might otherwise be sold
in timber sale activities.
· It is not nearly as effective if openings already have weIl-established competing
City of Ashland{.24
vegetation.
In appropriate' situations, however, natural regeneration can be planned for and
utilized to achieve reforestation objectives. The following considerations detennine the
effectiveness of any planned natural regeneration:
. Retention of numerous. cone-bearing overstory trees of preferred condition and species.
Not only is seed production from these trees critical, but they also moderate temperature
extremes that can cause a high percentage of mortality of young germinants, particularly
from frost damage at high elevations and/or heat damage on hot, dry aspects.
. An appropriate seedbed with high amounts of exposed mineral soil (which can be
developed through the use of prescribed fIre in the management area).
. Reduced competition for moisture from well-established ground vegetation (grass, forbs,
brush, etc.), and/or overstory trees; openings in stands have to be large enough such that
excess light, water, nutrients, and space are available for establishment of new treeS.
. Smaller stand openings or unit sizes that receive more seedfall per unit area than larger
units.
. Adequate moisture. particularly in the first season when small germinants are most
susceptible to mortality from lack of water.
. A minimal amount of livestock or big game activity that can trample and/or uproot the
tiny one-year-old seedlings.
Natural regeneration of conifers has obviously been largely successful throughout
most of the forested sites in the management area. Obviously, these stands can be managed
from now on such that natural regeneration can be relied upon to maintain fully stocked
City of AsWand/25
stands. It has not been successful, however, in some instances-most notably where brush
and/or hardwoods came in more rapidly and dominated the site following disturbance. If
regaining these sites in the near future is a priority, then artificial regeneration may be
required.
Artificial Re~eneration
In response to increasing harvests (particularly clearcuts) and large scale wildfires,
and the subsequent demand for adequate and immediate replanting of such areas, a fairly
sophisticated and technical reforestation process has been developed in recent years. Success
has been varied and depends on a long list of procedures which must all occur efficiently if
the reforestation effort is to be successful. These procedures include, but are not necessarily
limited to:
1. A good silvicuItural prescription matching the correct species and stock type
(elevation and seed zone) to the planting site;
2. Good nursery practices with production of good stock, preferably with large,
fibrous rooting systems;
3. Adequate lifting, sorting, packing, and storing of seedlings while in the nursery;
4. Efficient and careful handling of the seedlings from nursery to the outplanting
site with maintenance of seedlings in ideal storage conditions for temperature and
humidity;
5. GOOD PLANTING TECHNIQUES!
6. Good site preparation prior to planting and vegetation control techniques after
City of Ashlandf26
planting to optimize a seedling's opportunity for survival;
7. Control of damage from various animals, particularly deer and gophers.
Usually, a breakdown in anyone of these steps will insure seedlings' mortality.
More often, it is the less than optimal operation of several of these steps that combine to
sufficiently stress a seedling, with a subsequent increasing likelihood of mortality. It is a
tribute to professional forestry that successes occur as often as they do today.
Of critical importance throughout southern Oregon-and certainly on any artificial
regeneratiol). effort that would occur in the management area-is the control of incoming
competing vegetation that significantly stress a planted seedling. Site preparation (removal
of existing vegetation by manual, machine. fire, or occasionally chemical methods) prior to
planting provides the planted seedling with a good start at competing with other incoming
vegetation. Control of competing vegetation after planting is perhaps even more important
to seedling smvival. Mulching. spot application of herbicides, or continued scalping and/or
grubb.ing are the options for accomplishing this task, each with varying degrees of cost and
succ~. The decision as to which method to use to accomplish moisture control must remain
the responsibility of the owner, but regardless of technique the aggressive and effective
accomplishment of this task is absolutely imperative to successful reforestation.
Planting success in the management area would be most effective if completed in
February or early March. Seedlings should defInitely be of a similar seed zone and elevation
so that they match the site to be planted. Planning for the entire planting operation (reserving
equipment, seedlings, etc.; lining up those to accomplish the work, etc.) should be completed
in advance of the actual arrival date of the seedlings.
City of Ashland/27
In essence, it is important to understand that planting nursery-bred seedlings that
have undergone considerable stresses prior to actual insertion in the ground is a much
different process biologically than seedlings that are initiated from seedfall. Not only do
planted seedlings need much more care and optimal conditions, but are only planted 300 to
400 per acre per year as compared to repeated seeding of (often) thousands per acre in natural
regeneration. but on a more unpredictable schedule.
Timber Harvest
In sound silvicultural planning, timber harvest can be utilized to help reduce stand
densities so as to achieve certain (and often multiple) management objectives. If carefully
and professionally accomplished, timber harvest can move existing stands closer to the range
of historic conditions and hopefully offer greater potentials for long-term ecosystem stability
and/or viability.
Other than fire exclusion, the largest impacts in forest stand development occur
during that very short period of time when logging occurs. These impacts can be much more
profound than the simple reduction in aesthetic appeal that. is apparent to most lay people.
These impacts can include: obvious changes in the age, size, and species composition of
vegetation; damage to residual trees; potential loss of hard to replace older age classes that
have become increasingly uncommon throughout the Western United States; destruction of
a portion of understory vegetation; soil compaction if ground-based logging systems are
utilized; a redistribution of fuel loading with possibilities of dramatic increases in logging
slash and subsequent wildfrre potentials; possible increases in ideal deleterious insect habitat
"......,...,~~_..
City of Ashlandf28
(e.g., green slash) and/or disease substrates (e.g., fresh stumps); increased overland flow of
water and subsequent potential for erosion, stream sedimentation, and watershed deterioration;
changes in seral stages of vegetation with subsequent impacts on wildlife; rapid and radical
changes in nutrient cycling and availability; and numerous other lesser impacts.
Mitigating the numerous impacts from this infrequent, but potentially highly
impa~ting form of stand disturbance (logging) requires not only careful planning but very
'-
often professional help, particularly if a long-term, sustainable form of forest management is
desired. It is recommended that the City of Ashland retain a professional forester(s) to
oversee any proposed harvesting activities. That person(s) would oversee the following
activities, all necessary if a successful timber sale is to occur:
(1) Planning the harvest operation including designation of appropriate harvest
systems to achieve management objectives; location of property lines, comers,
and timber sale boWldaries; location of necessary roads, landings, and other
important harvest related features; etc.
(2) Pre-mark timber for removal to insure that the desired trees are removed (a
particularly important procedure to be accomplished professionally if stand
improvement is desired).
(3) Cruise the timber to be removed so that all parties (City of Ashland, prospec-
tive logging contractors, and log purchasers) can plan appropriately.
(4) Pre-designate yarding and falling patterns to limit soil compaction and
disturbance, stand damage, and potential logging costs.
(5) Pre-plan slash management and/or reforestation activities to be conducted by
City of Ashland/29
either the logging contractor or a separate contractor.
(6) Designate timing of operations to reduce the possibility of damage from
deleterious insects, as well as to limit damage to soil and watershed resources.
(7) Advertising the timber to be sold and contact potential log buyers to get the
highest possible price and to secure a valid purchase order. This is an art in
its own right, as each mill prefers logs of different species, sizes, grades, and
lengths. Travel distance to an interested mill can affect the outcome of the
bidding process, as well.
(8) Show the sale to several well-qualified logging contractors and obtain a
favorable price for accomplishing the job. Logging price can be considerably
variable depending on the type of logging and associated activities required, as
well as the capabilities of obtaining a market price from prospective logging
contractors.
(9) Prepare an appropriate logging contract to be reviewed by the City of Ashland.
(10) Acquire all necessary permits and insure that all appropriate laws and
regulations are being adhered to.
(11) Administer and supervise the 'actual sale implementation to insure that the job
is being accomplished as agreed, with minimal damage to residual stands,
advanced reproduction, soils, streams, aesthetic values, recreation sites, or other
important resource values.
(12) Oversee the accounting for all logs removed, subsequent development of scale
tickets and summaries, and proper distribution of monies to all participating
City of Ashland/30
parties.
Perhaps most iinportantly, the professional forester(s) must conduct the timber sale
in such a fashion as to prioritize silvicultural objectives desired by the owners.
Given that so much of the economic and ecologic value of a small' woodland
operation is determined and/or impacted during harvest activities, it is vitally important that
the C!ty of Ashland carefully plan prior to initiation of the project. Combining volumes from
seve~ properties to create a larger timber sale is an excellent way to improve the economies
of scale whereby improved prices from log purchaser and/or decreased costs for logging can
be obtained.
Although a well-planned and conducted logging can quickly revegetate with minimal
long-term impacts, inappropriate planning, construction, and/or maintenance of roads and skid
roads can continue to impact watersheds for decades after their initial installation. Sediment
entry into stream systems as a result of road surface erosion is usually much larger than that
from timber harvesting. Perhaps more importantly, roads intercept natural groundwater flow
'~.."
and subsequently channel water, allowing for much more rapid accumulation of high volumes
r.-
of water during peak storm events. It is in these situations that major erosion and watershed
deterioration can occur.
Less than optimal road construction techniques not only cause significant watershed
degradation, but can be quite expensive ~ well, as continued maintenance and/or road
rebuilding following failure can be even more costly over time than the original construction
costs.
Watershed values are of the highest priority for the City of Ashland owned lands in
_,.. .___k."'......_.._.~.__.____.._....._.~.....-...k
City of AshIand/31
the Ashland Watershed. The value of high quality water will obviously continue to rise
rapidly throughout the \Vestern United States, where water is usually at a shortage. Forest
management activities must be modified and/or tailored to prevent additional impacts to the
water resources of the Ashland Creek watershed. For this reason, it is recommended that no
additional roads be constructed in the implementation of forest management activities. The
very sensitive and erosive nature of the decomposed granitic soils in this area further
substantiate this course of action. Further, the existing granite pits and roads in the watershed
need considerable restoration and/or upgrading. It is recommended that the City of Ashland
retain the services of a consulting Engineering Geologist to address these important issues.
Due to the above critical concerns, harVest systems should be limited to the use of
helicopters only throughout almost all of the City-owned lands. Ground-based logging
systems would be inappropriate, except perhaps in the area inunediately adjacent the gravel
pits and/or narrow strips inunediately adjacent main access roads.
Helicopter logging, however, is expensive, with costs very sensitive to certain
attributes of timber sales. These often interrelated attributes include:
1. size of the logs to be removed;
2. average number of board feet per turn of logs;
3. the clustered or scattered nature of the logs to be removed and subsequent
volume per acre;
4. locations of available landings and roads, and subsequent average flight times;
5. the total volume of the sale.
Unfortunately, achieving silvicultural objectives can be very expensive when
,.,~,.....-_..,_._.
City of AshIand/32
helicopters are the intended harvest system. In this management area, the small size of the
logs suggested for remoVal, the scattered nature of those logs, the low volumes per acre, and
the low total volume all combine to suggest quite high helicopter logging costs, perhaps to
the point of superseding log value. Perhaps the most important of these is total log volume,
as the costs of merely moving a helicopter to a job can effectively negate its economic
viability if the total volumes are small. For this reason, the potential viability for such a sale
"
could be dramatically increased if additional volume outside the management area was
inclu~ed. It is unfortunate that considerable volume was removed from this management area
in 1990 by helicopter without an appropriate level of silvicultural planning to achieve other
objectives. The possibility of now re-entering this area in an economically viable stand
improvement harvest have been much reduced.
Although collecting fonnal cruise data was not part of this report, rough estimations
suggest that 150,000 to 250,000 board feet could be removed in a sanitation salvage/
co~ercial thin type of stand improvement harvest in the management area. Approximately
one-quarter to one-half of that volume consists of trees that have already died but yet are still
merchantable. However, these dead trees will rapidly decline, with perhaps as much as fifty
,
percent of existing standing dead volume per year decaying to a non-merchantable status.
Further, it is highly likely that additional trees will die each year unless planned silvicultural
activities upgrade stand health and vigor and hopefully reduce spreading bark beetle
infestation.
The negative impacts associated with no activity are described elsewhere in this
report, the most significant being an increasing wildfire hazard that is already extremely high.
......
City of Ashland/33
It is suspected that the inability to conduct a timber sale to remove these dead and dying
conifers (for whatever reason) would most likely then suggest paying for felling of many of
these snags for wildfIre prevention reasons. This would not only be expensive, but would add
additional and highly combustible ground fuels, mostly in highly undesirable locations
(adjacent the main haul road up the canyon where considerable mortality has already
occurred). An expensive piling and burning of this material, much as occurred in Lithia Park,
would probably also be necessary.
Strictly from a stand management viewpoint, a reduction in stand density will be
necessary in order to improve stand vigor and hopefully mitigate ongoing spread of bark
beetle induced mortality in the management area. Theoretically, this reduction can come from
any of the species and size classes within the stand. The City of Ashland could choose to
forego any harvest-related income and strictly reduce stand densities to appropriate levels
through pre-commercial thinning and release operation such as previously described. Many
existing and developing snags would then also have to be felled to meet wildfire prevention
objectives-an additional cost. On the contrary, it is not possible to "log our way to forest
health" in this situation; timber sales alone will not be sufficient to reduce stand densities to
appropriate levels to encourage forest health. Utilizing timber sales alone would be largely
a reactive approach (responding to ongoing insect or life killed timber), rather than a
proactive one. In fact, a simplistic approach of ongoing mortality salvage would prevent
ultimate development of the most fIre resistant stand t~ne dominated by larger overstory
conifers that occupy site resources and subsequently discourage development of dense
understory ladder fuels.
City of AsWand/34
It is suggested that treatment of both overstory (merchantable timber) and understory
vegetation will be necessary to achieve the objectives outlined by the City of Ashland.
Ideally, removal of overstory timber would be accomplished fIrst, because trees damaged in
that operation could be removed in the ensuing treatment of understory vegetation. However,
given that treatment of non-commercial vegetation is essential to accomplishment of the
City~ objectives for this management parcel, it is also possible that this work could be done
prior to timber harvest. Several disadvantages exist, however: (1) Some damage to already-
treated stands would occur during subsequent felling and yarding operations. (2) Selection
of leave trees during thinning/release operations could be complicated by not knowing which
merchantable trees would remain on-site after harvest. Logistically and perhaps politically,
however, it may be easier to conduct non-commercial silvicultural activities such as thinning
and release treatments, slash treatment, prescribed underbuming, fuelbreak construction, etc.,
than to initially attempt a helicopter timber sale. The economic viability of a timber sale is,
as y~!, undetermined and depends on a more accurate appraisal of projected timber volumes,
projected logging costs, and availability of helicopter logging contractors.
Fire Management
From ahnost any resource, social, or economic viewpoint, a watershed-level stand
replacement type of catastrophic wildfue is an extreme negative. Reducing the risk of that
type of fue in the Ashland Watershed is an obvious high priority.
In the absence of natural fue and/or an active thinning and fuel reduction program,
the chances for damage from wildfue have been steadily increasing to the point where the
City of Ashland/35
problem can now be considered extreme in most of the forests of Western North America,
and the AsWand Watershed is certainly no exception. In a careful and professional
assessment in the 1995 Bear Watershed Analysis (Ashland Ranger District, 1995), the
designated management area straddles the area delineated as the highest possible category for
fIre hazard and risk. Fire risk is particularly high in this area due to high likelihood of
ignition in the area. Since 1967, 53 rrres have occurred in the interface area outside of the
city limits of Ashland, and 93 percent of these rrres have been started by people (Ashland
Forest Plan, 1992). Personal communication with Bill Rose, Ashland Ranger District fire and
management officer, indicated that the management area is a particularly important location
from a landscape level wildfire management perspective because:
1. It is adjacent the area of highest rrre risk and most likely source of igni-
tion-the urban Ashland area and associated interface.
2. The narrow canyon topography of this location produces a "Venturi effect"
when daytime up valley winds are constricted, subsequently creating severe,
rapidly escalating fIre behavior in a wildfIre event.
Since fire intensity and rate-of-spread can escalate so rapidly, increasing the likelihood of
successful wildfrre suppression early in its initiation (i.e., in the lower watershed area) is
critical to preventing wholesale catastrophic stand replacement wiIdfrre. Preventing this type
of wildfrre is particularly important because of several very valuable "values-at-risk" in the
area:
- a largely unroaded and undisturbed forest ecosystem including considerable late
successional reserve and a research natural area.
,..___-.......--.~*__..,..O'. _."'_"'__"'_L_.~<'__'..,....'...~.,. .....____,.,._ __~ "
City of AsWand/36
- a watershed that provides the primary source of water for the City of AsWand.
- considerable urban and interface real estate values.
Fire requires three basic elements to occur--fuel, oxygen, and an ignition source.
Obviously, eliminating oxygen is not a viable alternative. Historically, the major thrust of
ftre prevention efforts (i.e., Smokey the Bear) has been to prevent ignition. Unfortunately,
ignition can never be totally prevented. Lightning, arson, carelessness, and accidents always
",""
insw:e that ftre will occur in forested settings. With fuel loadings increasing each year, the
chan~e for a "cool, low-intensity burn" in mid-summer, such as were the rule prior to the
Euro-American settling of the area, have long since passed. When burning at maximum rates
in southern Oregon, wildfire has consumed as much as 80 acres per minute.
It has increasingly become apparent that management of fuels, both green and dead,
provides the only long-term opportunity for returning the likelihood and subsequent intensity
of wildftre to safer prehistoric levels.. This is a premise which guides much of the
silvicultural prescriptions and ultimate stand management suggested in this report.
Productive fuels management 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 wildftre. Smaller diameter, fme flashy fuels are easy to ignite and encourage
rapid rate of spread of wildftre, while the opposite is true for larger fuels (although larger
fuels can greatly contribute to the ultimate intensity of wildftre).
Arrangement of fuels is important because dense, compacted fuels close to the
ground do not pose near the wildfrre hazard as do "ladder" fuels that form a constant fuel
,..
City of Ashland/37
source from ground into forest canopies. Snags are also a serious fuel arrangement problem
because, once ignited, sparks and fIfe can be spread great distances from their tops.
Fuel continuity is important because ftre spreads rapidly in continuous ground and
aerial fuels. Interrupting the horizontal continuity of fuels (fuelbreaks, roads, grasslands, etc.)
basically removes fuel from the fIfe, thereby preventing or at least slowing its spread.
Pruning of trees may help to further decrease the vertical continuity of fuels.
Once initiated, ftre behavior is detennined by weather, topography, and fuels. Even
though we cannot avoid the hotter, drier weather of summer; we can obviously develop much
greater care and concern during fIre season. Likewise there is little one can do about
topography, but knowing that fIfe spreads much more rapidly uphill and in higher wind
conditions one can analyze existing topography and subsequently prioritize wildfIfe prevention
and fuel reduction activities. The upper one-third of slopes are target areas for fuels
modiftcation because (1) they are usually the area of major suppression efforts during wildfIfe
events, and (2) the effects of convection and preheating upon fIfe behavior effectively end
at ridgetop locations.
Reducing the likelihood of severe destruction from wildfire depends, then, on an
aggressive proactive fuels modification and treatment program in the management area, as
well as in the Ashland Watershed as a whole. Three primai-y types of fuel reduction should
be considered and implemented: fuelbreaks and shaded fuelbreaks, defensible fuel prof1le
zones, and area-wide fuel reduction.
Fuelbreaks are strips of land on which native vegetation has been modified and
reduced such that fIfes burning into them are more easily controlled. Shaded fuelbreaks retain
,~-,.,._"._.,,-.~.."-,..
City of AsWand/38
a minimum number of healthy overstory trees with flammable understory vegetation largely
removed. Numerous fuelbreaks and shaded fuelbreaks have been installed in the area by the
U.S. Forest Service, Ashland Parks and Recreation, and several private landowners. Although
they can be constructed around homes, roads, or other improvements, they have been typically
constructed in strategic locations, particularly ridgetops, in the area. They historically have
been 150 to 250 feet wide, designed to effectively suppress encroaching small to medium-
sized wildtrres. Not only are fuels reduced in these locations, but frre fighting personnel have
easy access and aerial retardant can effectively reach the ground.
However, in severe frres, particularly those with excessive spotting, fuelbreaks have
often been ineffective. 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 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.
Finally, area-wide or landscape-level fuel reduction greatly decreases both the
likelihood and intensity of developing wildfrre, but usually occurs during the fmal phases of
a fuel modification program after the more highly-prioritized and cost-effective areas are
treated. In all three situations, effective planning can be conducted to coordinate fuels
reduction with simultaneous accomplishment of other silvicultural values. This is particularly
true in the larger scale fuels modifications activities, such as defensible fuel reduction zones
or area-wide fuel reduction.
-",. ._...,.._------,...._---"-,----.~-""'_.,-"...
...-
City of Ashland/39
In all of these approaches, removal and utilization of any marketable material (such
as logs, post and poles, firewood, etc.) is an excellent method of achieving fuels reduction
while garnering some income to offset expenses. Unfortunately, the costs of fuel (and
commodity) extraction may supersede the potential mcome, particularly when access is poor
or non-existent (except by helicopter), as is the case throughout almost all of the management
area.
In high priority areas, fuel reduction will most likely have to be done by
burning-either pile and burning and/or prescribed underburning. Pile and burning is the most
common form of fuel reduction using fire. Slash is piled and often covered with plastic to
facilitate burning in winter when little risk of fire escape exists. Swamper burI1}ng is similar
to pile burning except that 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. Prescribed underburning, however, can emulate the low intensity
surface rIres of the past. Surface fuels are burned in place, rather than piled and burned.
Prescribed burning is a much more exacting endeavor and demands a far greater professional-
ism, as the windows of opportunity are narrow. The opportunity to bum must fall within an
exact prescription in which fuels, weather, and logistics are all appropriately aligned to
achieve pre-detennined objectives. This endeavor obviously requires much greater levels of
pre-planning, and associated greater levels of risk.
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 fITe
danger. It must be noted that lop and scattering following thinning, although not as desirable
as other treatment techniques that remove it from the site, is certainly preferred to not
City of Ashland/40
thinning at all even from a wildfrre prevention point of view. Wildfrre danger is extreme in
dense, stagnant thickets of coniferous saplings, and even though downed slash from thinning
and release activities will represent an additional hazard for several years, the stand
improvement that results will encourage a rapid decrease in the vertical continuity of fuels
as trees grow and canopies become further removed from ground level. Too, improved vigor
of leave trees prevents the establishment of nwnerous snags-a potentially severe wildfrre
contI.ol problem. Slash should lose its fme fuel component (twigs and needles) within several
y~j. and in slowly compressing to ground level, wildfrre potential in the fuelbed will be
decreased.
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.
A comprehensive watershed level frre management strategy will provide the most
effecfi,ve possibility for wildfrre prevention and suppression. Coordination with the U.S.
Fo~t Service is imperative in this endeavor.
Planning for Biodiversity. Wildlife Habitat. and Long-term Site Productivity
Biodiversity is a commonly used term today describing a subjective measurement
of the different types of living organisms that reside in any given area. Two measures of
diversity are species diversity (the different species in a given area) and ecosystem diversity
(the different types of habitat that support various living organisms). Both species and
ecosystem diversity can be measured fairly accurately on the ground. Generally, however,
City of Ashland/41
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. The decline in numbers
of animals (such as Spotted Owls) are an outgrowth of such failures. The City of Ashland
is encouraged to participate with the Ashland Ranger District of the U.S. Forest SeIVice in
developing a coordinated plan for maximizing ecosystem diversity and wildlife habitat values
for the entire Ashland Watershed.
On a landscape level, a multiplicity of habitat values is highly desirable. For
example, in the deSignated management area, very little mature timber or late . successional
vegetation types exist, making this area largely unsuitable northern spOtted owl habitat.
However, as concluded in the 1995 Bear Watershed Analysis, maintaining favorable spotted
owl habitat is not possible on all acres all of the time and is particularly unlikely in the lower
Ashland Watershed where the designated management area occurs. Further, fuel reduction
activities that may eliminate multi-layered understories and subsequent sub-optimum spotted
owl habitat may yet be preferred in strategic locations to prevent catastrophic wildfIre and
su bsequent destruction of much greater amounts of late-successional species habitat (Ashland
Ranger District, 1995). Conversely, the younger vegetation and stand structures that currently
dominate the designated management area are much less common in the late successional
reserves higher in the watershed, and subsequently support wildlife species that prefer these
-..........-~'--,
City of Ashland/42
habitat conditions. Within the 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. Structural diversity goals may be secondary to wildfIre
prevention goals, given that large-scale disturbances such as large wildfires dramatically
reduce, if not eliminate, structural diversity. These biodiversity objectives can be best
achieved in areas not highly prioritized for fuels management, such as in riparian areas imd
in the lower half of the topography.
Snag retention is a particularly important biodiversity and wildlife habitat objective.
Over forty different species of birds and six species of manunaIs in southern Oregon rely on
snags, at least partially, to complete their lifecycles. Any larger snags (20 inch DBR and
larger) are particularly important as they offer increasingly rare nesting locations for some of
the manunaIs and larger birds that depend on them-and are a critical habitat feature that has
rapidly declined during the years of harvesting old growth. The Ashland Forest Plan
(McCormick and Associates, 1992) calls for retention of 4 to 7 snags and downed logs per
acre but also cautions that they should be placed "outside of natural wildfIre control lines."
Perhaps the most critical habitat for wildlife species and biodiversity objectives is
riparian habitat, a key feature of the Ashland Watershed. Although no riparian habitat occurs
within the designated management area, the City of Ashland is encouraged to again
coordinate with the Ashland Ranger District in the development of a coordinated management
of riparian habitat in the Ashland Watershed. The 1995 Bear Watershed Analysis (Ashland
City of Ashland/43
Ranger District, 1995) contains an excellent description of riparian and aquatic management
guidelines.
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. Unfortunately, fire suppression and exclusion has dramatically shifted the
percentage of total site nutrient capital above-ground (as opposed to below-ground). This
condition has likewise increased both the likelihood and intensity of fIre. As a result, these
higher-intensity wildfires of today are consuming a much greater percentage of total site
nutrient capital than the more frequent but less-intense flres of the pre-settler era-a
significant impact on long-term site productivity. Harvesting can do the same thing 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. Smaller harvest
entries and/or partial cuts with considerable green tree retention can usually maintain
satisfactory amounts of nutrient capital. Over 50 percent 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 during
harvesting. Of course, once again, these ideals must be balanced with critical fuel
management objectives.
It is also important to leave several large logs per acre on-site after harvest 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.
. _.,~...,...~..._ ....._.~~._____.4.".~"....._.,.__~. .,._....
City of Ashland/44
CHANGES IN RESOURCE VALUES RESULTING
FROl\f CHOOSING A ''NO ACTION" ALTERNATIVE
Disturbances of forests are important and ongoing events in the natural processes of
forest ecosystem development. In fact, it was our aggressive prevention of disturbance that
has contributed so significantly to the silvicultural predicaments that this report is attempting
to identify and address. Bark beetle infestation and subsequent tree mortality is a nonnal
occurrence in healthy forest ecosystems. The rapidity and the scale of its occurrence in the
management area and elsewhere in the immediate vicinity, however, is of great concem-
particularly given that it is occurring in a very important watershed adjacent very high real
estate values.
The change in stand conditions being rapidly created by bark beetle induced
mortality causes many direct and indirect changes affecting other resources as well, and must
be considered when determining management direction and subsequent activities. The
management choice to "do nothing" is, in effect, accepting the vegetational changes (such as
overstory conifer mortality) that will continue to occur, and perhaps even more rapidly.
Extensive conifer mortality obviously results in return of the vegetative community
to the earlier stages of succession. Species more well adapted to thrive in these new
conditions tend to dominate-particularly brush, grass, and broadleaved herb species. Trees
left undamaged, most notably hardwoods such as Pacific Madrone and the oaks, respond to
more favorable conditions and become even more dominant, in some cases even further
restricting the future development of conifers. Simultaneously, this vegetation type may also
encourage the wildlife species that depend on the earlier stages of succession.
City of Ashlandf45
Ongoing and extensive conifer mortality dramatically increases the potential for
damage from wildfIre. Standing snags are a serious wildfIre suppression problem, as they can
ignite and spew sparks from their tops, greatly increasing spotting and the subsequent rate of
spread of wildfIre. FaI1ing, burning snags can also represent serious safety hazards and
potential hazards to adjacent houses and/or real estate (even if the fire is otherwise maintained
at ground level). The developing dense understory vegetation following demise of overstory
conifers can be an even greater wildfIre hazard than dense overstory timber, as a large
distance between ground level and foliage in the crowns-a break in the vertical continuity
of the fuels-reduces rrre hazard. Overstory snags that fall into this developing dense ground
vegetation further exacerbate the developing fuel problem and wildfrre hazard. It is suspected
that this vegetation type (young, developing conifers, brush, and hardwoods with numerous
snags, both standing and down) was the fuel type that burned so intensely on northerly
aspects in 1910.
Rapid mortality of coniferous stands can also decrease slope stabilities, as roots die
and begin to lose their ability to hold soils in place. Although roots of incoming vegetation
slowly replace those of the previous conifers, there is a gap of time when soil stability is
significantly reduced. Often the incoming vegetation is not initially as deep-rooted as the
larger overstory conifers. It is for this reason that establishing of dense, shallow-rooted grass
species that prevent establishment of deeper-rooted native brush, hardwoods, or conifers is
not recommended as a long-term slope stability procedure.
Openings created by small patches of mortality in a dense stand of conifers can be
a positive development for wildlife habitat, however. The resulting stand has greater
".._'....,........~'~""_._'
City of Ashlandf46
variability in stand structure and vegetational diversity, both features that attract greater
numbers of species of wildlife per unit area. In essence, a greater amount of edge effect
results. However, with ongoing mortality (particularly of the kind that occurred in Uthia
Park and is currently beginning in portions of the management area) in which conifers are
totally removed from the stand, both stand structure and vegetational diversity ultimately are
reduced.
Snags are also important wildlife habitat features, but are not appropriate in areas
such as fuelbreaks which are designed to maximize wildfIre suppression capabilities. The
Ashland Forest Plan (McCormick and Associates. 1992, p. 47) specifically recommends "4
to 7 snags or large downed logs per acre outside of wiIdHre control lines. " Development of
an ongoing snag management policy should certainly be a long-term management objective
for City of Ashland owned forestlands and should be conducted on a watershed level through
coordination with the U.S. Forest Service, who owns most of the land in the watershed.
No spotted owls currently nest in the management area. The area is also not good
spotted owl habitat due to the younger ages and sizes of the coniferous timber in the stands
AND the lack of vertical structure and multiple canopy classes within the stands. The
ongoing mortality of older overstory conifers in the rilanagement area only further discourages
the development of stand conditions that can act as future spotted owl habitat. The increasing
fIre hazard and threat of large-scale stand destruction, returning vegetation back to the earlier
stages of succession, is a particularly undesirable "step backward" in development of
appropriate spotted owl habitat. Management activities designed to prevent a catastrophic
wildfue (such as described in this report) will hopefully allow for continuing development
.......
City of Ashlandf47
of stand structures favorable to spotted owls. Stand density reductions, both commercial and
pre-commercial, that are. designed to increase leave tree vigor, reduce bark beetle induced
mortality, and reduce the likelihood of stand replacement wildfire will hopefully continue to
allow the future development of spotted owl habitat values, while discouraging the destruction
of existing spotted owl habitat in the Ashland Watershed through decreasing the risk of
catastrophic wildfire. The Ashland Forest Plan (p. 46) specifically identifies this as a primary
goal: "Retain existing old growth as long as possible and manage younger trees in a manner
that they will become the replacement old growth as rapidly as feasible (McCormick and
Associates, 1992).
Aesthetic values vary by individual, but stands of contiguous bark beetle induced
conifer mortality are seldom considered aesthetically desirable. This has important
implications for long-term recreational possibilities in the management area. Several trails
utilized by mountain bikers and hikers already criss-cross the management area and the
presence of standing snags in these areas can obviously represent a potential liability.
Ongoing mortality and the resulting changes in stand conditions and resource values
will continue to negatively impact the primary objectives delineated for this area by the City
of Ashland: (1) protection of watershed values and maintenance of quality and quantity of
water for the City; (2) maintenance and/or promotion of forest and ecosystem health; and (3)
reduction in wildlIfe hazard and risk.
City of AshIandJ48
MANAGEMENT UNIT DESCRIPTIONSjPRESCRIPTIONS
The 105 acre management area has been subdivided into management units and
subunits based on given environmental site conditions, the suspected disturbance regime prior
to the time of Euro-American settlings, and the more recent management history. This
delineation of the property into management units and subunits will hopefully facilitate
unders~ding and implementation of desired management activities.
Several tenns are particularly important if one is to understand the descriptions and
prescriptions as described in the following section. These tenns-site index, rings per inch,
and basal area-generally refer to ways of understanding forested stands, and will now be
described in more detail.
Site index is a method of measuring and describing the potential productivity of any
given site, particularly for the groWth of conifers. Even sites that have no conifers (but could
have) have a site index, based on site productivity potentials for the existing soil type and
depth. Site index is usually determined by measuring heights and ages of dominant trees of
a given species in a stand. As a generalization, dominant conifers tend to grow to predictable
heights over time based on physical site characteristics and regardless of stocking levels. On
better sites, trees will grow taller in the same length oftime. Obviously, understory, diseased,
defective, and/or suppressed trees or trees in severely overdense stands cannot grow at these
rates and should not be included in site index measurements. Site index tables have been
constructed for all coniferous species, usually based on projected heights at 50 or 100 years.
The standard used in this report is 100 years and the number generated is the expected height
of dominant trees of a given conifer species on that site at age 100.
- ^-''''-'~'-~'^''-- ......
City of Ashland/49
Rings per inch refers to a way of measuring and describing a rate of growth of a
particular tree or, collectively, a group of trees. Since conifers typically add on one '"ring"
each year, the term rings per inch refers to the number of years needed for a tree to grow on
inch radially. The healthier and more vigorous a tree, the fewer the current number of rings
per inch. 'This figure can be used to assess changes in an individual tree's growth ("release"
following thinning or harvest; decline as stands become overcrowded, etc.) or to compare
trees or stands and subsequently make suggestions for management. Rings per inch is
detennined with an increment borer that drills and removes a small core from the tree.
Basal area is a very useful term used to determine the general density of trees within
any given stand. Its unit of measurement, square feet per acre, refers to the cross-sectional
area of all the stems in an acre of forest as measured at DBH. .'This is important because that
cross sectional area can be closely correlated with the amount of competition felt between
trees (or any vegetation for that matter) on a given site (Le., 160 square feet per acre is more
"dense" than 120 square feet per acre for a given site). Obviously, better sites can support
greater basal areas without excessive competition between trees. It is particularly useful in
thinning or harvesting projections because it can provide an idealized number to shoot for
regardless of variations in tree spacing or diameters. It is seldom that stands of conifers are
all of equal diameter or pre-treatment spacing. Obviously, ideal spacing should be different
after treatment for trees of different diameters. Since many diameters are typically left after
thirming or harvesting in native southern Oregon stands, basal area is a much more useful
guideline than spacing.
City of Ashland/50
Unit A - 8 acres
Description - Unit A is located on 35 to 55 percent easterly aspects on either side of Ashland
Loop Road in the northeastern corner of the management area. Unit A is comprised
of two subunits: AI' which was treated in the summer of 1995, and A2' whose
management history if similar to that throughout the remainder of the management
area. Prior to treatment, subunit Al was similar to many other places in the
management area in that the stand was significantly overdense and bark beetles had
already caused considerable mortality of Douglas-fir. Fire risk and hazard were both
extreme as well. The area was of particular concern due to its location immediately
adjacent valuable homes and property to the north and east. A stand density
reduction treatment was conducted in two phases: (1) a harvest of one log truck load
of dead merchantable Douglas-fIT located in the upper half of the unit and easily
, winched to roadside, (2) an understory thinning/release treatment to create more
.~ optimal stand densities. The resulting slash was piled and burned by an Americorps
crew hired by the City of Ashland. Stand densities went from pre-treatment
averages of 750 to 1,000 trees per acre and 175 to 200 square feet per acre to post-
treatment averages of 300 to 400 trees per acre and 100 to 125 square feet per acre.
Variation was considerable within the post-treatment unit, however, as part of the
area was considerably understocked due to complete mortality of Douglas-fir, while
other areas remained untouched, either by bark beetles or by treatment activities (i.e.,
the area within 50 feet of the topographical draw). Currently, about 50 percent of
the trees and stand basal area are Douglas-fir, 25 percent pacific madrone, and the
remainder primarily Ponderosa pine or California black oak. A more in-depth
prescription of this pre-treatment unit and explanations for silvicultural prescriptions
("Silvicultural Prescriptions for Two City of Ashland Owned Parcels") was
submitted by this company to the City of Ashland in Spring, 1995. Subunit A2 is
typical of the pre-treatment stand conditions in subunit AI' The stand is currently
in a rapid state of decline, with bark beetle induced mortality occurring from the
edges of the stand inward; in this case, proceeding southward and upward in
elevation. Mortality of almost all of the Douglas-fIT in a one-quarter acre patch has
occurred at the north end of Subunit A2. Further to the south and particularly closer
to ridgetop, 1/10 to X acre patches of Douglas-fir (presumably dead or dying) were
removed in the 1990 helicopter sale. Unfortunately, the residual trees left in both
of these areas were the small (less than 2 inches DBH), suppressed trees that have
yet to respond (and most likely will not respond) to the sudden increased availability
of water, light, nutrients, and space. Grass, forbs, creeping snowberry, poison oak,
and other ground covers have become dense in these areas, however. The remainder
of the unlogged portions of the unit are currently dominated by considerably
overdense stands averaging 200 to 225 square feet per acre, primarily of small, 6 to
12 inch DBH Douglas-fIT poles and similar sized Pacific madrone. Stand densities
decrease and mortality increases closer to the ridge to where site productivity
decreases and Ponderosa pine and California black oak form greater percentages of
"_'_~-<'-''''--'''''''- ~..
City of Ashland/51
the stand composition. Ponderosa pine are the healthiest, most vigorous conifers
throughout most of the subunit A2, and are particularly thriving where they have
been released by mortality and/or logging of adjacent Douglas-frr (growth has at
least doubled in these individual pines). Estimated 100 year site index is 95 to 105
for both Ponderosa pine and Douglas-frr.
Prescription - Subunit Al has already been treated with a thinning/release entry that should
be a model for similar work elsewhere on the property. The stand was purposely
left slightly overdense in this situation largely for aesthetic reasons. Stands treated
elsewhere on the property, including subunit A2' can be thinned slightly more
heavily, particularly if the stands are more vigorous than those in subunit Al and in-
stand mortality is less pronounced. Almost all of the remainder of the property will
need to be done (if desired) by helicopter, as opposed to the single load of logs
removed by ground based logging systems in this situation. The slash piles created
following the thinning/release treatment in subunit Al should be burned in the spring
of 1996. At that time, removal of the few trees that have died- (or are dying) in the
interim should be accomplished and incorporated into the slash piles. The ridge at
the top of Unit A and adjacent subunit BI is an ideal location to create a 200+ foot
wide shaded fuelbreak for the full length of the ridge on City of Ashland ownership
(approximately 1,500 feet). This 7 acre shaded fuelbreak should be a high
management priority and would offer an excellent place to stop advancing wildfrre
from either direction, and subsequently prevent considerable loss of important values
(urban real estate in one direction; Ashland Watershed in other direction). This
shaded fuelbreak would also tie-in with an existing shaded fuelbreak and defensible
fuel reduction zone on private land at the southern end of the unit. This private
parcel, treated by thinning and release from below followed by diligent slash
utilization/treatment, is an excellent example of very positive outcomes that can be
expected from proactive stand level treatments designed to achieve both silvicultural
and wildfrre prevention objectives. The remainder of Unit A and subunit BI should
also be prioritized for a defensible fuel reduction zone. In the remainder of Unit A,
stand density reduction similar to what occurred in subunit Al will be necessary to
restore health and vigor to the area. This should primarily be pre-conunercial
release treatments to remove understory competing vegetation and release preferred
leave trees. Although most of this work is precommercial, dead, dying, defective,
deformed, diseased, or heavily suppressed merchantable timber could be harvested
by helicopter if a property-wide sale can be developed. The close proximity of
Ashland Loop Road may allow utilization of some of the resulting slash if a
qualified and properly insured contractor can be found. The remaining slash should
be piled and burned. Slash created during the 1990 helicopter logging was untreated
and left in these openings, and should be piled and burned with developing thinning
and/or logging slash. In conjunction with pile burning in subunit Al and creation
of a shaded fuelbreak along the ridge, an excellent 300 to 600 foot, defensible fuel
reduction zone with good access (Ashland Loop Road) through the middle of it
City of Ashland/52
would be created. Implementing these fuel reduction treatments would change the
character oftheunofficial"Alice in Wonderland" hiking and mountain biking trail,
however, that runs along the ridgeline. Portions of this trail have also been deeply
eroded and creation of drainage devices (water bars, rolling dips) is suggested.
Small openings created during helicopter logging and/or bark beetle attack will
naturally regenerate over time and in the interim provide stand level structural
diversity. The hazard for slumping/landslides is less in this unit than in Unit D,
where immediate reforestation is suggested in a similar situation to help encourage
slope stability.
Unit B - 42 acres
Description - Unit B is comprised of 6 separate subunits located on 45 to 75 percent
;...; northerly to northwesterly aspects. These subunits are all comprised of even-aged,
considerably overdense stands of primarily Douglas-frr pre-commercial and small
commercial pole timber 6 to 12 inches DBH. These stands were initiated after the
1910 wildfIre and undoubtedly grew up in dense "doghair" thickets. The intense
competition undoubtedly allowed little differentiation between individuals and the
stands ultimately stagnated, with few healthy or vigorous individuals. This is
evidenced by their very small and thin crowns (few are over 30 percent crown
ratios) and very poor growth rates. In fact, even the occasional dominant 12 to 16
inch DBH conifers are growing at 15 to 20 rings per inch, with smaller trees
growing at 25 to 50 rings per inch. In this dense competition for site resources,
virtually all trees less than 4 inches DBH have died, and those less than 8 inches
DBH are either dying and/or extremely suppressed. An average of 800 to 1,000
trees per acre currently exist throughout Unit B, and basal areas average about 200
" square feet per acre, with small patches as high as 250 square feet per acre. These
'- are extremely high numbers for these types of stands and are indicative of severe
overcrowding. Douglas-frr comprises about three-quarters of that total basal area,
Pacific madrone about 15 percent, and the remainder in California black oak or the
rare Ponderosa pine, sugar pine, or incense cedar. Site productivity, tree diameter,
and tree vigor all decrease in upslope directions, with considerable mortality evident
on and near the ridgetop locations that are transitional with the less productive sites
on adjacent, more southerly aspects. Understory vegetation is sparse in these stands
where overstory trees utilize almost all of the site resources. However, creeping
snowberry, tall Oregon grape, grass, honeysuckle, and poison oak become much
more common in small openings, most notably in the powerline easement where
they combine with stump-sprouting Pacific madrone and California black oak,
Douglas-frr and incense cedar seedlings and saplings up to 10 feet tall, and other
more light-dependent shrubs such as deerbrush ceanothus and oceanspray. Estimated
100 year site index in Unit B is 105 to 115 for Douglas-frr.
-
City of Ashland/53
Prescription - Unit B has an existing stand condition that is a silvicultural nightmare. In the
absence of understory frre, manual thinning and release, or other methods of
reducing stand densities, the stands in Unit B have stagnated. Virtually the entire
stand of Douglas-fir is currently of poor vigor and very susceptible to attack and
demise from the cadre of insects that kill Douglas-frr. This very same condition and
scenario recently occurred one-half mile downcanyon to the north, where virtually
all of the Douglas-fir on more westerly aspects in Uthia Park were destroyed. In
this management area, Douglas-frr mortality is already occurring on more southerly
and westerly aspects in adjacent Units D and E, with associated slopover of
mortality into Unit B. Arresting this rapid mortality will be difficult to achieve
because the stand has been too long in a suppressed, weakened condition; it can only
slowly respond to the beneficial effects of reducing stand densities; and the beetle
population is already well established, if not exploding. Nonetheless, reducing stand
densities by manual thinning to release and improve the vigor of preferred leave
trees is the only possible option for reversing this decline. The success of this
endeavor will depend on a host of factors, the most important being the skill of the
individuals doing the work, the climate within the several years on either side of the
thinning operation, and the subsequent rapidity of spread of the bark beetle
population. More productive areas with more vigorous individual trees (Le., closer
to the creek) will fare better than more suppressed portions of the stands. Ideally,
stand basal areas can be reduced to 125 (1:25) square feet per acre, with the
thinning/release to largely be "from below," (Le., removing the most suppressed,
mostly pre-commercial conifers and hardwoods). However, it is estimated that
perhaps 15 to 25 percent of total stand volumes in Unit 8 could be removed in a
stand improvement harvest combining mortality (already dead but still merchantable)
and sanitation (dying, diseased, defective, deformed) salvage with commercial
thinning of merchantable, heavily suppressed conifers. Ideally, the commercial
harvest would occur first so that smaller trees damaged during this operation could
be removed in the subsequent non-commercial thinning/release operation.
Unfortunately, time is of the essence in Unit B, as bark beetles are poised to destroy
significant portions of the stands within the next several years. If tllls happens, not
only would the City of Ashland lose a considerable potential .fmancial resource, but
more importantly would greatly increase the frre hazard and risk while also
contributing to soil instability through subsequent loss of root strength. On the
contrary, a well conducted stand density reduction would hopefully:
- maintain the most vigorous trees on site that could rapidly respond to thinning
and subsequently progress to more fire resistant mature coniferous forest types;
- maintain deep-rooted, vigorous conifers that would continue to support healthy
roots and subsequent slope stability;
- maintain an actively growing stand of high quality, high grade conifers that could
represent an increasing fmancial value for the City (if desired);
- improve wildlife habitat, as stands were opened up, improving both species and
structural diversity (both horizontal and vertical).
...._...~......_._-"
City of Ashland/54
Harvesting would have to be done by helicopter to accomplish these multiple goals,
although it is still questionable as to whether a feasible helicopter sale is possible
because of small volumes of individual trees, small volumes per acre in a stand
improvement harvest, and small total amounts of volume (unless incorporated with
volume from other lands, either City-owned or neighbors).
An area-wide treatment of slash would obviously be the most desirable fuels
management strategy, with all logging and/or thinning slash piled and burned. If
this is not financially possible, concentrating piling and burning in the upper third
of each slope should be prioritized. This would be particularly important within
100+ feet of each ridgeline where shaded fuelbreaks would be prioritized (in
conjunction with adjacent Units C and E on more southerly aspects). The highest
priority location for these shaded fuelbreaks are (1) at the major ridgeline at the top
of Unit A in the northeastern comer of the property (associated with tops of subunits
~ BI' B2> B3' and BJ and (2) between subunits B2 and ~.
~.
Unit C - 10 acres
Description - Unit C is comprised of two subunits located in the very northernmost portion
of the management area. These two subunits are located on 35 to 55 percent
westerly to southwesterly aspects. These hotter, drier aspects generally have
shallower soils than adjacent, more northerly aspects, and these conditions combine
to encourage more drought-tolerant vegetation types. Whiteleaf manzanita
dominates Unit C, mostly in solid brushfields up to 10 to 15 feet tall. It is suspected
that these brushfields were initiated following either the 1900 or 1910 wildfIres
(most likely the 1910 wildfIre). Incorporated within these brushfields are occasional
" hardwoods (California black oak and, particularly, Pacific madrone), and Ponderosa
pine. These scattered Ponderosa pine (generally averaging around 50 trees per acre)
" are of variable ages and size, but typically range from 8 to 16 inches DBH and
overtopping the existing brush. They are under considerable competition from the
dense manzanita and many are likely candidates for mortality within the next 5 to
10 years if this condition does not change. Almost all of the Douglas-fIT (less
drought tolerant than Ponderosa pine) in Unit C have already died, and most have
decayed to the point where they are no longer commercially viable. Estimated 100
year site index is 80 to 90 for Ponderosa pine.
Prescription - Hot, dry slopes like those in Unit C undoubtedly burned frequently prior to the
advent of frre exclusion. As a result, they served a natural function as fuelbreaks
and prevented development of larger scale, high intensity wildfrres. In their current
fuel condition, however, they are extremely flammable during the summer season
and a significant wildfITe hazard. Major fuel reduction in Unit C is imperative and
should be a high management priority for the City-owned lands. This is particularly
important because of their location on the north edge of the City ownership, which
...~
City of Ashland/55
correspondingly is the lowest spot in the watershed. Hopefully, initial attack on a
fIre started within the city limits of Ashland (the most likely source for ignition) and
spreading upcanyon (the most likely direction of spread in swnmer days) could
contain a frre in this lower watershed area prior to developing into the type of
massive rrre that is difficult, if not impossible, to control. Management priorities in
Unit C call for major fuel reduction by hand removal of 75 to 90 percent of the
existing manzanita and hardwood cover. Complete clearing of manzanita should
occur in at least a 20 to 30 foot radius around existing isolated Ponderosa pine. In
places where the pines are more crowded, a maximum stocking level of 100 trees
per acre (20 foot spacing) is desired. Scattered Pacific madrone and/or California
black oak can be retained if they are not competing with preferred Ponderosa pine.
Several narrow bands of hardwoods and brush can be strategically retained in the
unit to provide for soil stability, erosion control to maintain vegetational and
structural diversity and to promote habitat diversity for wildlife. However, brush
and hardwood removal should be prioritized as a wildfrre prevention activity fIrst
and foremost, and breaking up of horizontal fuel continuity is imperative. Once
complete, Unit C can serve as a defensible fuel reduction zone, particularly in
subunit ~, where it will anchor into the proposed shaded fuelbreak on the ridge
between subunits ~ and B2. Complete removal of manzanita should occur in a 75
to 100 foot swath along the ridgeline B.j~ fuelbreak. All snags in the fuelbreaks
should be felled (unless they can be economically retrieved in a timber sale planned
for the remainder of the property), and piled and burned.
This extensive brushfield reclamation and fuel reduction can also serve as site
preparation for planting of reduced levels of Ponderosa pine, perhaps on a 15-foot
spacing. Control of incoming competitive weed species would be essential to insure
survival of planted conifers. Ultimately, these would develop into overstory pine in
a pine-savanna vegetation type that would remain much less frre prone than the
existing dense brushfields. The seedlings will have to be carefully managed,
however, to maintain their viability (control of competing vegetation) while insuring
they don't contribute to lITe hazard (pruning, pre-commercial thinning if necessary).
It may be appropriate to experiment with planting native grasses (a much less
volatile fuel type) in the new openings to discourage developing brush and
hardwoods.
Unit D - 13 acres
Description - Unit D is comprised of two subunits located on 45 to 75 percent westerly
slopes immediately above Ashland Creek. These locations near the canyon bottom
are generally more productive than sites higher in the landscape. The 95-year-old
conifers in these units reflect this, as diameters are significantly larger than
elsewhere in the management area. Douglas-fir overstory trees 16 to 28 inches DBH
are common. Unfortunately, stand densities have also historically been quite high
.".,~.~-...............-,_..,.,-_.__.
City of Ashland/56
until recently when bark beetles have initiated significant mortality. The combina-
tion of high basal areas, larger stems preferable to bark beetles, and an expanding
bark beetle population encouraged development of a bark beetle epidemic in the
Douglas-frr in portions of this unit. Approximately one-third of the basal area in
Unit D (which averaged close to 200 square feet per acre prior to the initiation of
beetle-induced mortality) has already died, mostly in expanding patches of mortality.
Patches within these areas were originally logged in the 1990 helicopter logging,
which retrieved this dead or declining timber, but obviously did little to improve
stand health such that ongoing mortality could be reduced. It is expected that this
trend will continue, with 5 to 20 percent of the remaining green Douglas-fir killed
,. annually through the next several years. In addition, existing merchantable dead
trees will continue to decay and lose potential commercial viability, as well as
significantly contribute to wildfrre hazard in the area. With the significant mortality
- in Unit D, basal areas currently average 125 to 150 square feet per acre, although
mortality is complete in several 1 to 2 acre patches of merchantable Douglas-frr.
These openings, coupled with the often-associated helicopter logged patches have
become rapidly revegetated with dense creeping snowberry, grasses, forbs, and other
plants. Elsewhere in the unit where mortality has not been as significant, Douglas-
fir still comprises two-thirds or more of the stand basal area, with Pacific madrone
the next most common tree (15 to 20 percent of stand basal area). Typical of these
types of dense stands in the management area, understory vegetation is sparse.
Estimated 100 year site index is 110 to 120 for Douglas-frr, indicative of the high
productivity of these sites. Given this high productivity, the ongoing demise of
Douglas-frr is that much more unfortunate.
Prescription - The coniferous stands in Unit D are in a rapid state of decline, with at least
one-third of the stand already killed by the advancing bark beetles. Reversing this
trend in the remainder of the stand will be difficult at best, but basically involves
stand density reductions to try to optimize residual tree vigor. A fair number,
perhaps 5 to 10 percent of the original stand, have died since the 1990 helicopter
logging and are too far gone to be commercially viable. Some of these (4 to 7 per
acre) could be maintained as snags for wildlife (this area is not as serious of a frre
hazard as higher on the landscape), although this hazard may conflict with
recreational use of the area (an apparently new trail has been created that starts in
subunit D.. traverses until it reaches the BJCz ridge, then follows that ridge up to
the Alice in Wonderland trail on top of the main ridge). Ideally, the remaining dead
merchantable trees could be removed in timber sale(s) prior to their decay and
ultimate commercial uselessness. Several old roads parallel the main road up the
canyon and allow access for harvest and removal of perhaps one-quarter to one-third
of the standing dead volume by ground-based logging systems. (An in-depth
discussion of the pros, cons, and potential impacts of logging using ground-based
logging systems in a similar situation was prepared by the author for the City of
Ashland in "Silvicultural Prescriptions for Two City of Ashland Owned Parcels,"
~....~u...._~~.,,_.....___..... ...~
City of Ashland/57
1995.) The steep slopes would allow little opportunity for log skidding off of these
old skid roads, however, thereby requiring the use of helicopters throughout the
remainder of the unit. In portions of the unit that still support green Douglas-fIr, a
combination of mortality/ sanitation salvage and commercial thinning combined with
non-commercial thinning and release treatment could initiate the stand density
reduction necessary to hopefully retain some of the larger size classes in the unit.
Some of this material may be available for utilization as fIrewood given its close
proximity to the main Ashland Creek canyon road. The large bulk of the slash will
have to be piled and burned, however. Good slash treatment and overall fuel
reduction are important in this unit because of the heavier concentrations of people
(workers, vehicles on the road, hikers and mountain bikers, etc.) and subsequent
greater potential for ignition source. These steep slopes are particularly prone to
mass soil movements, particularly given the ongoing mortality of the deep-rooted
overstory conifers. In those areas where the conifers have already been removed by
bark beetles, however, spot planting of Douglas-fIr on a 12-foot spacing should be
undertaken to quickly re-establish deep-rooted conifers in these steep portions of
Unit D. Control of competing vegetation in a 3 to 4 foot radius around each
seedling will be imperative for seedling survival.
Unit E - 28 acres
Description - The highly dissected topography typical of the erosive granitic parent materials
found in the management area produces the series of adjacent and opposing aspects
and subsequent site conditions described in this report. Unit E comprises 4 subunits
in this series located on 35 to 65 percent westerly to southwesterly aspects and
adjacent the opposing northerly aspects of Unit B. These hotter, drier sites are very
similar to those in Unit C and site productivities are similarly reduced. However,
unlike Unit C, where whiteleaf manzanita thoroughly dominates the sites, vegetation
in Unit E is more diverse. Unlike Unit B where stand replacement frres in 1910
created a single even-aged stand of Douglas-fir, Unit E is dominated by several age
classes and species of trees, with each age class largely initiated after one of a series
of disturbances. The generally reduced amounts of vegetation and subsequent fuel
loads on these less productive sites encouraged fIres of reduced intensity, with
patches of overstory conifers escaping mortality in each disturbance event. Thus,
the existing stands in Unit E much more closely resemble an "uneven-aged" stand
configuration. Scattered throughout Unit E are 1/4 to one-acre pockets of older
Douglas-frr and Ponderosa pine 125 to 200 years old (it appears that at least several
fIres occurred during this period, with perhaps the most significant frre occurring
approximately 150 years ago, as this age class is the most common of these larger
trees) and 18 to 30 inches DBH. These are trees that escaped frres and logging
activity. They are seldom contiguous patches, however, as numerous conifers and
hardwoods have invaded since the last fire 85 years ago, severely threatening the
~,.....,..~................""-_..
City of Ashland/58
\':
long-term viability of these scattered trees. Invariably, these trees are in poor to fair
(at best) condition, commonly averaging 30 to 50 rings per inch or more. A number
of these were also removed during the 1990 helicopter logging, possibly as mortality
salvage at that time. Most of the overstory conifers in Unit E, however, are 85 to
95 years old, having been initiated following the major fires in 1900 and 1910.
These trees are typically 10 to 18 inches DBH. Logging of scattered larger
merchantable conifers appears to have occurred throughout Unit E in the late 1930$
(conifers in adjacent Unit B were mostly too small to be merchantable at that time).
Openings created during this harvest, coupled with the greater abundance of non-
stocked openings on these harsher sites, has allowed establishment of smaller
advanced regeneration of Ponderosa pine, Douglas-frr, hardwoods, and brush species
(primarily whiteleaf manzanita and occasional deerbrush ceanothus, mountain
mahogany, oceanspray, and other less common species). Unfortunately, in the
absence of frre in the last 85 years, the hardwoods (primarily Pacific madrone and
California black oak) and brush species have become much more abundant,
'contributing to a much more continuous fuel complex (both horizontally and
vertically) throughout the unit and competing with the existing conifers for site
resources. Numerous overstory Douglas-frr (both merchantable and pre-merchant-
able) have died in Unit E, although not to the extent as is currently occurring in Unit
D. The greater abundance of openings (often now dominated with brush) reduced
site productivities, and history of logging and bark beetle induced mortality has
resulted in reduced stand basal areas-typically averaging 75 to 100 square feet per
acre in non-brushfield areas. Douglas-frr, Ponderosa pine, and hardwoods
(particularly Pacific madrone) generally comprise equal portions of that total stand
basal area, although this can vary dramatically from microsite to microsite.
Ponderosa pine invariably appears to be more vigorous and healthy than Douglas-fir.
Incense cedar (primarily in the understory) and sugar pine (primarily in the overstory
as rare large dominant trees) also occur. Understory vegetation is more common on
these more open sites and includes more abundant grass, forbs, and tall Oregon
grape, as well as the aforementioned brush species. One hundred year site index is
95 to 105 for Ponderosa pine, 85 to 100 for Douglas-fir.
:',"
""'1,.
Prescription - Prior to the era of frre exclusion and subsequent dramatically increased fuel
levels, the harsher sites and reduced levels of vegetation in Unit E (like Unit C)
acted as natural fuelbreaks on a landscape level. With more frequent, low intensity
fire, slow growing hardwoods (when initiated from seed) and brush species were
unable to dominate sites as they do currently in Unit E. A return to these conditions
would significantly reduce the likelihood, as well as intensity and rate-of-spread, of
a wildfue. In addition, established conifers, particularly Ponderosa pine, would
garner a greater percentage of site resources (most importantly, water) and be
considerably more vigorous, thereby resisting bark beetle attack and adding volume
onto larger, more thrifty trees. Stand density reduction through manual release
operations, coupled with removal of competing brush species, would achieve these
~~"'___~...._,.<o.._, .4
City of Ashland/59
desired future conditions. Ponderosa pine and sugar pine would be preferred leave
trees throughout Unit E, although maintaining a diversity of species and age classes
is certainly possible and even desirable. Thinning slash should be piled and burned,
or perhaps prescribed underburned, with particular emphasis on ridgeline locations
(similar to that described for fuelbreaks in Unit C). Existing merchantable dead or
dying, deformed, defective, diseased, or heavily suppressed conifers can be removed
in a helicopter logging wherever volume is clustered enough to warrant their
economic removal (provided a property-wide helicopter sale can be developed and
sold). Treatment of subunit ~ is of particular priority because it is larger and wider
than the other subunits and would offer the most significant defensible fuel reduction
zone. The bottom, most westerly part of this subunit is a particularly harsh site with
an inherent reduced amount of vegetation, making establishment of a good fuel
reduction zone through this area that much more feasible. Too, treatment of subunit
~ would tie into the existing defensible fuel reduction zone on private land just east
of the property, providing a significant 6OO-foot wide fuel reduction zone, running
close to one-half mile wide in an east to west direction.
Unit F - 4 acres
Description - Unit F is a unique unit in the management area. It is located on 35 to 55
percent southerly aspects and, given this location, could have been included as a
subunit of Unit C or perhaps more appropriately Unit E. Unit F was apparently
burned in both frres around the turn of the century (the 1900 event and the 1910
event), as trees of both ages were found. Unlike the rest of Unit C or Unit E,
however, these trees developed into a fairly contiguous stand dominated primarily
by conifers. Currently 300 to 500 trees per acre comprise an average stand basal
area of 175 square feet per acre. Ninety percent of that total is comprised of
conifers-Douglas-frr (about 60 percent) and Ponderosa pine (about 30 percent),
mostly in the 10 to 18 inch DBH size class. This high percentage of well developed
conifers of merchantable size classes and corresponding low percentage of
hardwoods (primarily Pacific madrone and to a lesser extent California black oak)
is unusual on these aspects in this management area-hence, its delineation as a
separate unit. It does point, however, to the potentials for stand development that
are possible if conifers can gain early establishment at full stocking levels (unlike
Units C and E) and develop without becoming stagnant (as in Unit B). Nonetheless,
the unit is considerably overstocked, as evidenced by poor crowns (although not a5
reduced as in Unit B), slow growth rates (typically 25 to 40 rings per inch, even in
the overstory dominant trees), and beginning in-stand mortality. However, adjacent
the powerline easement (where all trees were removed approximately 23 years ago),
the positive effects of stand density reduction were obvious. One vigorous, 20 inch
DBH Ponderosa pine was immediately released at the time of clearing for the
powerline and instantly improved its growth rate from 25 to 7 rings per inch. This
'-..........-...'..."...'.--..
City of Ashland/60
is the type of leave tree response desired throughout Unit F, as well as throughout
the management area as a whole. Understory vegetation is sparse underneath this
dense stand, and few developing coniferous seedlings or saplings exist. One
hundred year site index is 95 to 105 for Ponderosa pine; 90 to 100 for Douglas-fIr.
Prescription - Unlike most of the southerly to southwesterly aspects in the management area,
the stand in Unit F is not only contiguous, but contains a number of overstory
dominant conifers in fair to good condition. Even though located on harsher sites
than those in adjacent Unit B, the reduced number of trees per acre (300 to 500 as
opposed to 800 to 1,000 in Unit B) allowed those trees to grow faster, more
vigorously, and to larger sizes in the same time period. Less mortality from bark
beetle infestation is a subsequent benefit of these healthier stand conditions.
Nonetheless, the stand is currently considerably overstocked, of reduced vigor, and
available to additional bark beetle induced mortality, particularly given the beetle
population and extensive overstory mortality in adjacent subunit DI' Therefore, a
reduction in stand density is imperative to prevent further decline of this stand. The
larger size classes in this stand (and the reduced number of hardwoods and brush
species) suggest that the type of non-commercial release treatments suggested for
elsewhere on southerly aspects would not reduce stand densities to the desired basal
areas of 100 to 125 square feet per acre. Commercial thinning as part of a larger
helicopter sale in the area is the most feasible way to accomplish the needed stand
density reduction in this 'unit. Removal of merchantable dead, dying. diseased,
defective, or heavily suppressed conifers should be accomplished at the same time.
The key to successful stand improvement in this situation is to retain the most
vigorous conifers in the stand, which are almost invariably the largest. Treatment
of ensuing slash could be accomplished through pile and burning or prescribed
. underburning. This would be a particularly good location for a prescribed
underburn, particularly if a well developed and implemented fuelbreak (a high
priority) on the ridge above (Unit Ct) is in place. The ensuing stand condition
(provided it is accomplished prior to excessive additional bark beetle induced in-
stand mortality) would be a model of future desired conditions for vegetation on
these aspects, particularly from a fuel management or wildfrre prevention perspec-
tive.
"-'~-'-"""'."'"""- ......
City of Ashland/61
PRIORITIZATION OF NON-COM.MERCIAL SILVICULTURAL ACTIVITIES*
Listed in order of importance
Unit or Cost Total
Subunit Activity Acres per Acre Cost
1. Al Bum piles, plant seedlings 3 $300-600 $900-1,800
in openings
2. AJBI Shaded fuelbreak 7 $1,000-1,300 $7,000-9,100
construction-dlln, pile, bum
3. BJc'" Fuelbreak construction-thin 9 $1,100-1,400 $9,900-12,600
and brush, pile, bum
4. D Plant 400 conifers per acre 4 $325-425 $41,300-1,700
in unstocked openings, con-
trol competing vegetation
5. D Non-conunercial release 13 $250-350 $3,250-4,550
treatment
6. BI' B2 Non-conunercial thin & re- 19 $250-350 . $4,750-6,650
lease
7. D, BI. Pile and bum slash; utilize 32 $300-600 $9,600-19,200
B2 where possible.
8. CI, C". Brushfield reclamation- 9 $1,300-1,600 $11,700-14,400
brush, pile, burn, plant
9. ~, A2 Non-conunercial thin and 17 $250-350 $4,250-5,950
release
10. ~,Az Pile and burn slash 17 $300-600 . $5,100-10,200
11. B3,. Non-conunercial thin and 23 $250-350 $5,750-8,050
B4' Bs, B6 release
12. EI' Non-conunercial thin and 14 $250-350 $3,500-4,900
~, E4 release
13. B3, Slash treatment-pile and 37 $300-500 $11.100-18.500
B4' Bs, B6' burn and/or prescribed
EI' ~, E4 underburn
TOTAL: $77,700-116,800
* See map for location of activities.
,.".--.,......-..__...,. ........~"'~.."~,,....,...~'~~"..N_._, .,.___,. ,
"
PAIORITIZATI.ON OF 'NoN-GOtrtmIR(I~L.
51 LV'I '~L TlltlI\L. "'TaYITIES
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~---~-_.._.",-_..."."..,,_._,. ...-
City of Ashland/62
COl\f1\lERCIAL SILVICULTURAL ACTIVITIES
City of Ashland personnel responsible for the management of lands addressed in
this report should consider exploring the possibility, and feasibility, of a timber harvest to
remove merchantable dead and dying conifers and to improve stand conditions.
A small timber sale using ground based logging systems could be conducted from
established roads and quarries in the bottom of Ashland Creek canyon. This could
retrieve dead and dying volume primarily in Unit D and perhaps small portions of Units B
and/or E. Logging equipment would be largely restricted to existing roads, quarries, and
old pre-existing skid roads. The sale would be a small one-perhaps 5,000 to 25,000
board feet and be relatively easy to undertake. The costs of such a logging would range
from $200 to $400 per thousand board feet.
Helicopter logging will be needed to conduct mortality-sanitation salvage and
stand improvement harvesting throughout almost the entire management area addressed by
this report. Helicopter logging must be done on a much larger scale than ground-based
logging, largely due to the extreme high costs of operating a helicopter and subsequent
economies of scale. It is debatable whether sufficient volumes could be generated in the
management area alone to justify a helicopter timber sale. Rough estimates suggested
150,000 to 250,000 board feet could be generated in a stand improvement/salvage harvest
within the management area. Contrast this figure with the 1,400,000 board feet removed
in the 1990 logging operation in the general vicinity on City of Ashland and adjacent
private lands. Including additional volume from City of Ashland owned lands and/or
other adjacent private lands is certainly prudent, and may be necessary in order to
generate a timber sale using helicopters.
Planning for a helicopter sale is also more complex and time consuming,
particularly when stand improvement objectives are prioritized. The timber volume would
have to be marked and cruised prior to being shown to prospective logging contractors
and/or potential purchasers. There are far fewer helicopter logging contractors and
subsequent increased likelihood that a sale could remain unsold, especially if the sale
contains smaller total volumes.
As to be expected, the cost of helicopter logging can be much more variable,
with ranges from $250 to $500 per thousand board feet (if the sale is sold at all) delivered
to mill. Log prices in the last several years for second growth Douglas-fIr have ranged
from $650 to $800 per thousand board feet delivered at mill.
~.............~.~~~.._. ........._..-.."-~,...."..~,-_... ....--.-.............,.. ..-,..-. . .~.-
City of Ashland/63
OTHER NEEDED MANAGEMENT ACTIVITIES
Develop restoration/maintenance plan for granite quarries and roads; hire consulting
engineering geologist.
Develop proactive recreation management plan for management area.
Maintain 4 to 7 snags per acre in non-fuel treatment areas.
Coordinate with U.s. Forest Service in development of watershed level planning for
multiple resource values (wildfire prevention, wildlife habitat. aquatic and
riparian management, recreation management, etc.)
City of AshlandJ64
LITERATURE CITED
Ashland Ranger District. 1995. "1995 Bear Watershed Analysis."
McCormick, R. L., and Associates. May 1992. "Ashland Forest Plan."
Rose, Bill. 1995. Fire Management Officer, Ashland Ranger District. Personal conunu-
nication.
Small Woodland Services, Inc. 1995. "A Preliminary Assessment of Forest and Resource
Management Priorities on City of Ashland Owned Lands."
Small Woodland Services, Inc. 1995. "Silvicultural Prescriptions for Two City of
Ashland Owned Parcels."
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PAIORITtzATION OF N~-GOfr'mEI(CI~j.
51 LVI ('~L TllllAL. AtTIVITIES
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SOIL SURVEY OF JACKSON COUNTY AREA.
OREGO
i I " , ; I " , ~,1 ef- T c, d' '" I) (C U I ) f~ ii, "
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260
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when heavy equipment is used. Puddling can occur
when the soil is wet. Using low-pressure ground
equipment causes less damage to the soil and helps to
maintain productivity. Compaction can be minimized by
using suitable methods of harvesting, laying out skid
trails in advance, and harvesting timber when the soil is
least susceptible to compaction. Ripping skid trails and
landings when the soil is dry can improve the growth of
plants.
Erosion can be controlled by carefully planning the
construction and maintenance of logging roads, skid
trails, and landings. Seeding, mulching, and benching
areas that have been cut and filled also help to control
erosion. Skid trails and unsurfaced roads may be
impassable during rainy periods, Logging roads require
suitable surfacing for year-round use.
A high temperature in the surface layer and an
insufficient moisture supply in summer increase the
seedling mortality rate. To compensate for the expected
high mortality rate, the larger seedlings or a greater
number of seedlings should be planted. When the
timber is harvested, leaving some of the larger trees
unharvested provides shade for seedlings.
Reforestation can be accomplished by planting Douglas
fir and ponderosa pine seedlings.
Undesirable plants limit natural or artificial
reforestation unless intensive site preparation and
maintenance measures are applied. Mulching around
seedlings helps to maintain the moisture supply in
summer and minimizes competition from undesirable
plants.
Increased erosion, loss of plant nutrients, and water
repellency are ,likely to result from fires of moderate
intensity.
The vegetative site is Douglas Fir-Mixed Pine-Fescue
Forest.
165E-Shefflein loam, 20 to 35 percent north
slopes. This deep, well drained soil is on hillslopes. It
formed in colluvium and residuum derived from granitic
rock. Elevation is 1,000 to 4,000 feet. The mean annual
precipitation is 25 to 40 inches, the mean annual
temperature is 46 to 54 degrees F, and the average
frost-free period is 100 to 160 days. The native
vegetation is mainly conifers and hardwoods and an
understory of grasses, shrubs, and forbs.
Typically, the surface layer is dark brown loam about
4 inches thick. The next layer is reddish brown loam
about 6 inches thick. The upper 30 inches of the subsoil
is reddish brown clay loam. The lower 16 inches is
reddish brown sandy clay loam, Weathered bedrock is
at a depth of about 56 inches. The depth to bedrock
ranges from 40 to 60 inches. In some areas the surface
layer is sandy loam or clay loam,
Soil Surv':t
Included in this unit are small areas of Ruch,
Vannoy, and Voorhies soils; Tallowbox soils on the
more sloping parts of the landscape and on convex
slopes; poorly drained soils near drainageways and On
concave slopes; and soils that are similar to the
Shefflein soil but have bedrock at a depth of more thar
60 inches. Also included are small areas of Sheff/ein
soils that have slopes of less than 20 or more than 35
percent. Included areas make up about 20 percent at
the t6\al acreage.
Permeability is moderately slow in the Shefflein soil
Available water capacity is about 8 inches, The effect IV'
rooting depth is 40 to 60 inches. Runoff is medium. anc
the hazard of water erosion is high.
This unit is used for timber production and wildlife
habitat. It is suited to the production of Douglas fir and
ponderosa pine. Other species that grow on this un,t
include incense cedar, sugar pine, and Pacific mac,on(
The understory vegetation includes deerbrush, tall
Oregon grape, and western fescue.
On the basis of a 100-year site curve, the mean Slle
index for Douglas fir is 110. The yield at culmination 0'
the mean annual increment is 5.880 cubic feet per am'
in a fully stocked, even-aged stand of trees at 60 years
and 48,300 board feet per acre (Scribner rule) at 140
years. On the basis of a 50-year curve, the mean site
index is 80.
On the basis of a 100-year site curve, the mean Slt(,
index for ponderosa pine is 115. The yield at
culmination of the mean annual increment is 5.280
cubic feet per acre in a fully stocked, even-aged stand
of trees at 40 years and 56,780 board feet per acre
(Scribner rule) at 110 years,
The main limitations affecting timber production are
erosion, compaction, plant competition, and seedling
mortality. When timber is harvested, management ;ha:
minimizes the risk of erosion is essential. Wheeled an,::
tracked logging equipment can be used in the less
sloping areas, but cable yarding generally is safer In 1'"
more sloping areas and results in less surface
disturbance. Using standard wheeled and tracked
equipment when the soil is moist causes rutting and
compaction. Puddling can occur when the soil is we!
Using low-pressure ground equipment causes lesS
damage to the soil and helps to maintain productlvll\
Compaction can be minimized by using suitable
methods of harvesting, laying out skid trails in advanc~
and harvesting timber when the soil is least suscept1b,
to compaction, Ripping skid trails and landings wtlen
the soil is dry can improve the growth of plants
Properly designed road drainage systems that ~'
. I e'05''-'
Include carefully located culverts help to contro " ed
Areas that have been cut and filled are eaSily erod
I:
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Soil
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,:I
,..Jackson County Area. Oregon
261
~,
Figure 11.-Severely eroded roadcut in an area of Shefflein loam, 20 to 35 percent north slopes.
unless they are treated (fig. 11), Seeding. mulching,
and benching these areas help to control erosion. Steep
yarding paths. skid trails. and firebreaks are subject to
nlling and gullying unless they are protected by a plant
~ver or adequate water bars. or both, Cutbanks
~asionally slump when the soil is saturated.
This unit is subject to slumping. especially In areas
2dJacent to drainageways. Road failure and landslides
\ likely to occur after road construction and
-tlarcutting, Skid trails and unsurfaced roads may be
iI'Tlpassable during rainy periods, Logging roads require
. SUit bl
1, a e surfacing for year-round use.
_ ~ Undesicable plants limit nalucal DC a,'ilic,al
reforestation unless intensive site preparation and
maintenance measures are applied, Reforestation can
be accomplished by planting Douglas fir and ponderosa
pine seedlings, Mulching around seedlings helps to
maintain the moisture supply in summer and minimizes
competition from undesirable plants,
A high temperature in the surface layer and an
insufficient moisture supply in summer increase tile
seedling mortality rate, To compensate for tile expected
high mortality rate. the larger seedlings or a grea:er
number of seedlings should be planted When ttl{~
timber is harvested. leaving some of the larger trees
unharvested provides shade for seedlings
-,.....-~-' ..<
262
Increased erosion, loss of plant nutrients, and water
repellency are likely to result from fires of moderate
intensity,
The vegetative site is Douglas Fir-Mixed Pine-Fescue
Forest.
166E-Shefflein loam, 20 to 35 percent south
slopes. This deep, well drained soi~is on hillslopes. It
formed in colluvium and residuum derived from granitic
rock, Elevation is 1,000 to 4,000 feet. The mean annual
precipitation is 25 to 40 inches, the mean annual
temperature is 46 to 54 degrees F, and the average
frost-free period is 100 to 160 days, The native
vegetation is mainly conifers and hardwoods and an
understory of grasses, shrubs, and forbs.
Typically, the surface layer is dark brown loam about
4 inches thick. The next layer is reddish brown loam
about 6 inches thick. The upper 30 inches of the subsoil
is reddish brown clay loam. The lower 16 inches is
reddish brown sandy clay loam. Weathered bedrock is
at a depth of about 56 inches. The depth to bedrock
ranges from 40 to 60 inches. In some areas the surface
layer is sandy loam or clay loam or is stony.
Included in this unit are small areas of Ruch,
Vannoy, and Voorhies soils; Tallowbox soils on the
more sloping parts of the landscape and on convex
slopes; and soils that are similar to the SheHlein soil but
have bedrock at a depth of less than 40 or more than
60 inches, Also included are small areas of poorly
drained soils near drainageways and on concave slopes
and Shefflein soils that have slopes of less than 20 or
more than 35 percent. Included areas make up about
20 percent of th'e total acreage.
Permeability is moderately slow in the Shefflein soil.
Available water capacity is about 8 inches. The effective
rooting depth is 40 to 60 inches, RunoH is medium, and
the hazard of water erosion is high.
This unit is used for timber production and wildlife
habitat. It is suited to the production of ponderosa pine
and Douglas fir, Other species that grow on this unit
include incense cedar, sugar pine, and Pacific madrone.
The understory vegetation includes deerbrush, tall
Oregon grape, and Idaho fescue.
On the basis of a 1 OO-year site curve, the mean site
index for ponderosa pine is 100. The yield at
culmination of the mean annual increment is 4,080
cubic feet per acre in a fully stocked, even-aged stand
of trees at 40 years and 44,640 board feet per acre
(Scribner rule) at 120 years.
On the basis of a 100-year site curve, the mean site
index for Douglas fir is 100. The yield at culmination of
the mean annual increment is 5,040 cubic feet per acre
in a fully stocked, even-aged stand of trees at 60 years
and 39,750 board feet per acre (Scribner rule) at 150
Soil Surv,:;
Ja
years. On the basis of a 50-year curve, the mean S11E:
index is 70.
The main limitations affecting timber production art-
erosion, compaction, seedling mortality, and plant
competition. When timber is harvested, management
that minimizes the risk of erosion is essential. Wheelec
and tracked logging equipment can be used in the ies,
sloping areas, but cable yarding generally is safer 11 !t.
more sloping areas and results in less surface
disturbance. Using standard wheeled and tracked
equipment when the soil is moist causes rutting and
compaction. Puddling can occur when the soil is wet
Using low-pressure ground equipment causes less
damage to the soil and helps to maintain productivity
Compaction can be minimized by using suitable
methods of harvesting, laying out skid trails in advano
and harvesting timber when the soil is least susce;:Jllbl..
to compaction. Ripping skid trails and landings when
the soil is dry can improve the growth of plants.
Properly designed road drainage systems that
include carefully located culverts help to control erOSIO'
Areas that have been cut and filled are easily eroded
unless they are treated. Seeding, mulching, and
benching these areas help to control erosion. Steep
yarding paths, skid trails, and firebreaks are subject 10
rilling and gullying unless they are protected by a plan:
cover or adequate water bars, or both. Cutbanks
occasionally slump when the soil is saturated.
This unit is subject to slumping, especially in areas
adjacent to drainageways. Road failure and landslides
are likely to occur after road construction and
clearcutting. Skid trails and unsurfaced roads may be
impassable during rainy periods. Logging roads requH'
suitable surfacing for year-round use.
A high temperature in the surface layer and an
insufficient moisture supply in summer increase the
seedling mortality rate. To compensate for the expeC!i
high mortality rate, the larger seedlings or a greater
number of seedlings should be planted. When the
timber is harvested, leaving some of the larger trees,
unharvested provides shade for seedlings. The seed
mortality rate also can be reduced by providing ar1lf:~,:
shade for seedlings. Reforestation can be accompll~
by planting Douglas fir and ponderosa pine seeol1ng:
Undesirable plants limit natural or artificial
reforestation unless intensive site preparation and .
maintenance measures are applied (fig, 12). MU)Ch,r:.
around seedlings helps to maintain the moisture suP:,
in summer and minimizes competition from undes,ra. .
plants. .
Increased erosion, loss of plant nutrients, and wa:c
repellency are likely to result from fires of moderate
intensity.
f'
.~ .
{:
;
F1~
Fa!
Thl
tori
lIJt1
Ille
ani
'v{
- flat
l'\c.
'1;'-
li/i;
<3
me timber is harvested, leaving some of the larger trees
unharVested provides shade for seedlings,
Increased erosion, loss of plant nutrients, and water
repellency are likely to result from fires of moderate
intensity.
The vegetative site is Douglas Fir Forest.
188G- Tallowbox gravelly sandy loam, 35 to 70
percent north slopes. This moderately deep, somewhat
excessively drained soil is on hills lopes, It formed in
colluvium derived from granitic rock, Elevation is 1,000
to 4,000 feet. The mean annual precipitation is 25 to 40
inches, the mean annual temperature is 46 to 54
degrees F, and the average frost-free period is 100 to
160 days. The native vegetation is mainly conifers and
hardwoods and an understory of grasses, shrubs, and
forbs.
Typically, the surface is covered with a layer of
needles, leaves, and twigs about 1 inch thick. The
surface layer is dark brown gravelly sandy loam about 6
inches thick. The upper 6 inches of the subsoil is dark
brown sandy loam. The lower 11 inches is brown
- 'elly sandy loam. Weathered bedrock is at a depth
ro. dbout 23 inches. The depth to bedrock ranges from
to 40 inches.
Included in this unit are small areas of Caris,
Offenbacher, Vannoy, and Voorhies soils; soils that are
similar to the Tallowbox soil but have bedrock at a
depth of less than 20 or more than 40 inches; and
Tallowbox soils that have slopes of less than 35 or
more than 70 percent. Included areas make up about
15 percent of the total acreage.
Permeability is moderately rapid in the Tallowbox
soil. Available water capacity is about 3 inches. The
effective rooting depth is 20 to 40 inches, Runoff is
rapid, and the hazard of water erosion is high.
This unit is used for timber production and wildlife
habitat. It is suited to the production of Douglas fir and
ponderosa pine. Other species that grow on this unit
include incense cedar, sugar pine, and Pacific madrone.
The understory vegetation includes cream bush
oceanspray, common snowberry, and tall Oregon grape.
On the basis of a 100-year site curve, the mean site
index for Douglas fir is 100. The yield at culmination of
the mean annual increment is 5,040 cubic feet per acre
in a fully stocked, even-aged stand of trees at 60 years
ard.. 39,750 board feet per acre (Scribner rule) at 150
y, .. On the basis of a 50-year curve, the mean site
jn.;ex is 70.
)n the basis of a 100-year site curve, the mean site
index for ponderosa pine is 100. The yield at
culmination of the mean annual increment is 4,080
cubic feet per acre in a fully stocked, even-aged stand
Soil Sur J':.,
,laC~
of trees at 40 years and 44,640 board feet per acre
(Scribner rule) at 120 years.
The main limitations affecting timber production ar,:
the slope, erosion, compaction, plant competition. ana
seedling mortality. Also, the bedrock restricts root
growth. As a result, windthrow is a hazard.
When timber is harvested, management that
minimizes the risk of erosion is essential. Wheelec Jnc
tracked logging equipment can be used in the less
sloping areas, but cable yarding generally is safer "no
results in less surface disturbance. Using standard
wheeled and tracked equipment when the soil is mOIS~
causes rutting and compaction. Puddling can Occur
when the soil is wet. Using low-pressure ground
equipment causes less damage to the soil and helps Ie
maintain productivity. Compaction can be minimized b)
using suitable methods of harvesting, laying out skid
trails in advance, and harvesting timber when the S81i I'
least susceptible to compaction. Ripping skid trails i1nc
landings when the soil is dry can improve the growth 0'
plants.
Properly designed road drainage systems that
include carefully located culverts help to control eroSlor
Areas that have been cut and filled are easily eroded
unless they are treated. Seeding, mulching, and
benching these areas help to control erosion. Steep
yarding paths, skid trails, and firebreaks are subjec: to
rilling and gullying unless they are protected by a Oiant
cover or adequate water bars, or both, Cutbanks
occasionally slump when the soil is saturated.
This unit is subject to slumping, especially in areas
adjacent to drainageways. Road failure and landslides
are likely to occur after road construction and
clearcutting.
Constructing logging roads on the steeper slopes car
result in a high risk of erosion. Building the roads a:
midslope requires extensive cutting and filling and
removes land from production. Material that is
discarded when the roads are built can damage
vegetation and is a potential source of sedimentation ,.
the material becomes saturated, avalanches of debns
can occur. End hauling of the waste material minimizes
damage to the vegetation downslope and reduces Ihe
risk of sedimentation. Skid trails and unsurfaced roaGS
may be impassable during rainy periods, Logging raile:
require suitable surfacing for year-round use.
Undesirable plants limit natural or artificial
reforestation unless intensive site preparation and
maintenance measures are applied, Reforestation can
be accomplished by planting Douglas fir and ponderosa
pine seedlings. Mulching around seedlings helpS to
maintain the moisture supply in summer and minimizes
competition from undesirable plants,
A high temperature in the surface layer during
sum
t1B~
expE
Orea
tIlet
unh,
In
rape
Illter
Tt
H
perc
soml
ridge
Elev
prec
tem~
frost
vege
unde
T\
neec
surf,
inch!
bra\/.
gray
of at
20 tc
In
Vam
but t
than
slopi
slop!
on C'
Tallc
mOrf
15 p
PI
soil.
effec
med
TI
habi
and
inclu
The
Ore~
o
inde
Of th
acre
_ _1.
Jackson County Area, Oregon
summer and the low available water capacity increase
Ihe seedling mortality rate. To compensate for the
expected high mortality rate, the larger seedlings or a
greater number of seedlings should be planted. When
the timber is harvested, leaving some of the larger trees
unharvested provides shade for seedlings.
Increased erosion, loss of plant nutrients, and water
repellency are likely to result from fires of moderate
Intensity.
The vegetative site is Douglas Fir Forest.
189E- Tallowbox gravelly sandy loam, 20 to 35
percent south slopes. This moderately deep,
somewhat excessively drained soil is on hillslopes and
ndges, It formed in colluvium derived from granitic rock,
Elevation is 1,000 to 4,000 feet. The mean annual
precipitation is 25 to 40 inches, the mean annual
. temperature is 46 to 54 degrees F, and the average
trost-free period is 100 to 160 days. The native
vegetation is mainly conifers and hardwoods and an
understory of grasses, shrubs, and forbs.
Typically, the surface is covered with a layer of
needles, leaves, and twigs about 1 inch thick. The
surtace layer is dark brown gravelly sandy loam about 6
inches thick. The upper 6 inches of the subsoil is dark
brown sandy loam. The lower 11 inches is brown
gravelly sandy loam. Weathered bedrock is at a depth
of about 23 inches. The depth to bedrock ranges from
20 to 40 inches.
Included in the unit are small areas Offenbacher and
Vannoy soils, soils that are similar to the Tallowbox soil
but have bedrock at a depth of less than 20 or more
than 40 inches, Caris and Voorhies soils on the more
Sloping parts of the landscape, Ruch soils on toe
slopes, and poorly drained soils near drainageways and
On concave slopes. Also included are small areas of
Tallowbox soils that have slopes of less than 20 or
more than 35 percent. Included areas make up about
1S percent of the total acreage.
Permeability is moderately rapid in the Tallowbox
soil. Available water capacity is about 3 inches. The
eHective rooting depth is 20 to 40 inches. Runoff is
medium, and the hazard of water erosion is high.
This unit is used for timber production and wildlife
habitat. It is suited to the production of ponderosa pine
and Douglas fir. Other species that grow on this unit
II\clude incense cedar, sugar pine, and Pacific madrone.
The understory vegetation includes deerbrush, tall
Oregon grape, and Idaho fescue.
On the basis of a 100-year site curve, the mean site
lI'Idex for ponderosa pine is 90, The yield at culmination
Of the mean annual increment is 3,400 cubic feet per
acre in a fully stocked, even-aged stand of trees at 40
~ ~~}
289
years and 37,960 board feet per acre (Scribner rule) at
130 years.
On the basis of a 100-year site curve, the mean site
index for Douglas fir is 90. The yield at culmination of
the mean annual increment is 4,200 cubic feet per acre
in a fully stocked, even-aged stand of trees at 60 years
and 31,840 board feet per acre (Scribner rule) at 160
years, On the basis of a 50-year curve, the mean site
index is 60.
The main limitations affecting timber production are
erosion, compaction, seedling mortality, and plant
competition. Also, the bedrock restricts root growth. As
a result, windthrow is a hazard.
When timber is harvested, management that
minimizes the risk of erosion is essential. Wheeled and
tracked logging equipment can be used in the less
sloping areas, but cable yarding generally is safer in the
more sloping areas and results in less surface
disturbance. Using standard wheeled and tracked
equipment when the soil is moist causes rutting and
compaction. Puddling can occur when the soil is wet.
Using low-pressure ground equipment causes less
damage to the soil and helps to maintain productivity,
Compaction can be minimized by using suitable
methods of harvesting, laying out skid trails in advance,
and harvesting timber when the soil is least susceptible
to compaction. Ripping skid trails and landings when
the soil is dry can improve the growth of plants.
Properly designed road drainage systems that
include carefully located culverts help to control erosion.
Areas that have been cut and filled are easily eroded
unless they are treated. Seeding, mulching, and
benching these areas help to control erosion. Steep
yarding paths, skid trails, and firebreaks are subject to
rilling and gullying unless they are protected by a plant
cover or adequate water bars, or both. Cutbanks
occasionally slump when the soil is saturated.
This unit is subject to slumping, especially in areas
adjacent to drainageways. Road failure and landslides
are likely to occur after road construction and
c1earcutting. Skid trails and unsurfaced roads may be
impassable during rainy periods. Logging roads require
suitable surfacing for year-round use.
A high temperature in the surface layer during
summer and the low available water capacity increase
the seedling mortality rate. To compensate for the
expected high mortality rate, the larger seedlings or a
greater number of seedlings should be planted. When
the timber is harvested, leaving some of the larger trees
unharvested provides shade for seedlings. The se~~II,ng _
mortality rate also can be reduced by providing artifICial .
shade for seedlings. Reforestation can be accompllshec..
by planting Douglas fir and ponderosa pine seedlings,
Undesirable plants limit natural or artificial
?
r~lorestation unless intensive site preparation and
maintenance measures are applied. Mulching around
seedlings helps to maintain the moisture supply in
summer and minimizes competition from undesirable
plants.
Increased erosion, loss of plant nutrients, and water
repellency are likely to result from fires of moderate
intensity,
The vegetative site is Mixed Pine-Douglas Fir-Fescue
Forest, Granitic,
189G- Tallowbox gravelly sandy loam, 35 to 60
percent south slopes. This moderately deep,
somewhat excessively drained soil is on hillslopes. It
formed in colluvium derived from granitic rock. Elevation
is 1,000 to 4,000 feet. The mean annual precipitation is
25 to 40 inches, the mean annual temperature is 46 to
54 degrees F, and the average frost-free period is 100
to 160 days, The native vegetation is mainly conifers
and hardwoods and an understory of grasses, shrubs,
and forbs.
Typically, the surface is covered with a layer of
nep-dles, leaves, and twigs about 1 inch thick. The
s :::e layer is dark brown gravelly sandy loam about 6
les thick. The upper 6 inches of the subsoil is dark
IVn sandy loam. The lower 11 inches is brown
gravelly sandy loam, Weathered bedrock is at a depth
of about 23 inches. The depth to bedrock ranges from
20 to 40 inches,
Included in this unit are small areas of Caris,
Offenbacher, Vannoy, and Voorhies soils on concave
slopes or on the less sloping parts of the landscape;
soils that are similar to the Tallowbox soil but have
bedrock at a depth of less than 20 or more than 40
inches; and Tallowbox soils that have slopes of less
than 35 or more than 70 percent. Included areas make
up about 15 percent of the total acreage.
Permeability is moderately rapid in the Tallowbox
soil. Available water capacity is about 3 inches. The
effective rooting depth is 20 to 40 inches. Runoff is
rapid, and the hazard of water erosion is high.
This unit is used for timber production and wildlife
habitat. It is suited to the production of ponderosa pine
and Douglas fir. Other species that grow on this unit
include incense cedar, sugar pine, and Pacific madrone.
The understory vegetation includes deerbrush, tall
Oregon grape, and Idaho fescue.
On the basis of a 1 OO-year site curve, the mean site
in for ponderosa pine is 90. The yield at culmination
Of tne mean annual increment is 3,400 cubic feet per
in a fully stocked, even-aged stand of trees at 40
years and 37,960 board feet per acre (Scribner rule) at
130 years,
On the basis of a 1 OO-year site curve, the mean site
Soil Sur I': .
index for Douglas fir is 90. The yield at culmination c'
the mean annual increment is 4,200 cubic feet per ac'.
in a fully stocked, even-aged stand of trees at 60 yea"
and 31,840 board feet per acre (Scribner rule) at , 60
years. On the basis of a 50-year curve, the mean Site
index is 60.
The main limitations affecting timber production are
the slope, erosion, compaction. seedling mortality. 3nc
plant competition. Also, the bedrock restricts root
growth, As a result, windthrow is a hazard.
When timber is harvested, management that
minimizes the risk of erosion is essential. Wheeled anr.
tracked logging equipment can be used in the less
sloping areas, but cable yarding generally is safer anc
results in less surface disturbance. Using standard
wheeled and tracked equipment when the soil is mOtS'
causes rutting and compaction. Puddling can occur
when the soil is wet. Using low-pressure ground
equipment causes less damage to the soil and helps Ie
maintain productivity. Compaction can be minimized b\
using suitable methods of harvesting, laying out skid
trails in advance, and harvesting timber when the sod "
least susceptible to compaction. Ripping skid trails anc
landings when the soil is dry can improve the growth 0'
plants.
Properly designed road drainage systems that
include carefully located culverts help to control ercslor
Areas that have been cut and filled are easily eroded
unless they are treated. Seeding, mulching, and
benching these areas help to control erosion. Steep
yarding paths, skid trails, and firebreaks are subject 10
rilling and gullying unless they are protected by a plan!
cover or adequate water bars, or both. Cutbanks
occasionally slump when the soil is saturated.
This unit is subject to slumping, especially in areas
adjacent to drainageways. Road failure and landslices
are likely to occur after road construction and
clearcutting.
Constructing logging roads on the steeper slopes Cil'
result in a high risk of erosion. Building the roads at
midslope requires extensive cutting and filling and
removes land from production. Material that is
discarded when the roads are built can damage
vegetation and is a potential source of sedimentation '
the material becomes saturated, avalanches of debllS
can occur. End hauling of the waste material minln~,zt?:
damage to the vegetation downslope and reduces lrlt?
risk of sedimentation. Skid trails and unsurfaced roads
may be impassable during rainy periods. Logging roado
require suitable surfacing for year-round use.
A high temperature in the surface layer during
summer and the low available water capacity increase
the seedling mortality rate. To compensate for the
expected high mortality rate, the larger seedlings or a
flson
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~ timbE
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The v
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Inclu
SOils; 8
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Jackson County Area, Oregon
greater number of seedlings should be planted. When
me timber is harvested, leaving some of the larger trees
unharvested provides shade for seedlings. The seedling
mortality rate also can be reduced by providing artificial
shade for seedlings. Reforestation can be accomplished
bY planting Douglas fir and ponderosa pine seedlings.
Undesirable plants limit natural or artificial
reforestation unless intensive site preparation and
maintenance measures are applied. Mulching around
seedlings helps to maintain the moisture supply in
summer and minimizes competition from undesirable
plants.
Increased erosion, loss of plant nutrients, and water
repellency are likely to result from fires of moderate
Intensity.
The vegetative site is Mixed Pine-Douglas Fir-Fescue
Forest, Granitic.
190E- Tatouche gravelly loam, 12 to 35 percent
north slopes. This very deep, well drained soil is on
hillslopes. It formed in colluvium derived dominantly
trom andesite, tuff, and breccia, Elevation is 3,600 to
5,500 feet. The mean annual precipitation is 30 to 50
Inches, the mean annual temperature is 40 to 45
degrees F, and the average frost-free period is less
than 100 days, The native vegetation is mainly conifers
and an understory of grasses, shrubs, and forbs.
Typically, the surface is covered with a layer of
needles and twigs about 2 inches thick. The surface
layer is very dark brown gravelly loam about 11 inches
thick. The upper 8 inches of the subsoil is dark brown
gravelly clay loam. The lower 41 inches is dark brown
clay. The substratum to a depth of 73 inches is strong
brown clay loam. The depth to bedrock is 60 inches or
more. In some areas the surface layer is stony or
CObbly,
Included in this unit are small areas of Pinehurst
SOils; Bybee, Kanutchan, and Sibannac soils near
drainageways and on concave slopes; Farva soils on
COnvex slopes; and soils that are similar to the
Tatouche soil but have bedrock within a depth of 60
Il'lches, Also included are small areas of Tatouche soils
that have slopes of less than 12 or more than 35
Dercent. Included areas make up about 20 percent of
:he lotal acreage.
A. P,ermeability is moderately slow in the Tatouche soil.
r "'a~lable water capacity is about 8 inches. The effective
OOllng depth is 60 inches or more. Runoff is medium,
arI(j the hazard of water erosion is moderate,
This unit is used for timber production, livestock
~~i~g, a~d wild,life habitat. .
arI(j hiS unit, IS SUited to the production of D~ugla~ fir
'lei Whl~e fIT, Other species that grow on thiS unit
ude Incense cedar and ponderosa pine. The
291
understory vegetation includes creambush oceanspray,
cascade Oregongrape, and whitevein shinleaf.
On the basis of a 100-year site curve, the mean site
index for Douglas fir is 125. The yield at culmination of
the mean annual increment is 7,320 cubic feet per acre
in a fully stocked, even-aged stand of trees at 60 years
and 58,200 board feet per acre (Scribner rule) at 120
years. On the basis of a 50-year curve, the mean site
index is 90,
The main limitations affecting timber production are
erosion, compaction, plant competition, and seedling
mortality. Wheeled and tracked logging equipment can
be used in the less sloping areas, but cable yarding
generally is safer in the more sloping areas and results
in less surface disturbance. Using standard wheeled
and tracked equipment when the soil is moist causes
rutting and compaction. Puddling can occur when the
soil is wet. Using low-pressure ground equipment
causes less damage to the soil and helps to maintain
productivity, Compaction can be minimized by using
suitable methods of harvesting, laying out skid trails in
advance, and harvesting timber when the soil is least
susceptible to compaction, Ripping skid trails and
landings when the soil is dry can improve the growth of
plants.
Properly designed road drainage systems that
include carefully located culverts help to control erosion.
Seeding, mulching, and benching areas that have been
cut and filled also help to control erosion. Steep yarding
paths, skid trails, and firebreaks are subject to rilling
and gullying unless they are protected by a plant cover
or adequate water bars, or both. Skid trails and
unsurfaced roads may be impassable during rainy
periods. Logging roads require suitable surfacing for
year-round use.
Undesirable plants limit natural or artificial
reforestation unless intensive site preparation and
maintenance measures are applied. Reforestation can
be accomplished by planting ponderosa pine and
Douglas fir seedlings. Mulching around seedlings helps
to maintain the moisture supply in summer and
minimizes competition from undesirable plants.
Severe frost can damage or kill seedlings. In the less
sloping areas where air drainage may be restricted,
proper timber harvesting methods can reduce the effect
of frost on regeneration.
The main limitations affecting livestock grazing are
compaction and erosion. The native vegetation suitable
for grazing includes western fescue, mountain brame,
and Alaska oniongrass. If the understory is overgrazed,
the proportion of preferred forage plants decreases and
the proportion of less preferred forage plants increases.
A planned grazing system that includes timely
deferment of grazing, rotation grazing, and proper