HomeMy WebLinkAboutDensity Proposal 2002
Density Management: Second Phase
Very Early Working Draft Proposal #2 1-09-02
(Opinions and preferences are included but do not represent the entire Commission. They
are displayed in italics to provide examples of decisions that need to be made)
Background And Need
The City has been working for the past six years to thin small trees and brush on City-owned
forest lands. This work has focused on thinning small diameter understory trees (less than
7@ diameter); these have been carefully burned in small piles. This has been sufficient to
reduce ladder fuels and create stable stands in some areas but there are still many stands
with very high density of larger trees that are seriously stressed during drought periods and
subject to beetle attack as well as other, slower stress related mortality.
Based on detailed forest inventories, and silvicultural assessments, it is clear that the City
needs to proceed with a second phase of thinning on its lands in the watershed. Many of the
forest stands are precariously overstocked due to the suppression of natural fires in the
watershed. The goal of this second phase of density management is to remove weak trees in
understory and mid-layer in order to attain a stand density that is sustainable over the long
term. The focus of this thinning will be on stand health though there will be an associated fire
hazard reduction as a result of reduced tree density.
There are many areas of moderate to high geologic hazard where there is a distinct conflict
between the goal of reducing tree density to assure stand health and maintaining maximum
tree cover to guarantee slope stability. Up to this point the Commission has deferred any
activity in these areas (with one exception). The problem with continuing to ignore these
areas, however, is that sooner or later a drought event will lead to accelerated tree mortality
and we will lose the trees that are holding the soil in place. As part of this project we are
recommending treatments which we hope will resolve this conflict.
As part of the planning for this next phase of the thinning, we need to clarify what the Desired
Future Condition (DFC) of the various stand types is. This process will be interdisciplinary
and look at a variety of resources essential for maintenance of forest health including healthy
soils, stable slopes, water supply, fire hazard, large dead and down woody materials, and the
broad category of Aprotecting biodiversity@ which includes managing for the maintenance of
all existing native animal, plant and fungi species.
Goals
· Reduce forest stand densities to levels that allow the potential for sustaining healthy
forest stands for the long term,
· Maintain "full site occupancy" by trees on most of the forest lands; maintain the largest
trees.
· increase ground layer vegetation including mosses and native grasses.
· Protect and improve riparian transition zone habitat
· Develop an approach for reducing stand density while protecting slope stability in
moderately geologically sensitive areas (hazard 2 zones).
,....- -
Guiding Principles
As has been the case up to now, the thinning activities will be ecosystem driven (we assume
that financial resources will be available to implement). No trees will be cut simply to add
value to a timber sale. The goal will be to thin just enough to allow remaining trees to survive
during drought periods. The core element of this will be a commitment to carefully determine
which trees are needed (to be left) in the stand to maintain optimal stand and forest health.
Of those which are cut, only logs that are in excess of what is optimal for soil development
and wildlife needs (balanced with fire hazard considerations) will be removed to be sold.
· The trees to be cut will mostly be in the age class of 20 -90 years old; this is the age
class that has grown as a result of our fire suppression efforts since 1910. There will
be some trees cut in older age classes if it is determined to be necessary for the
health of the stand.
· What we cut or girdle should not be just a function of age.. .it could be a low vigor tree
(a tree with a live crown ratio less than 30% (for Douglas fir) or 25% (for pines and
hardwoods))
· Thinning Will Be Conservative In Scope: There is a range of stand densities which
are suitable for healthy stand growth. In this project the upper end of this range will be
the target. In other words we would rather err on the side of leaving too many trees
rather than thinning too many. By this approach we will be leaving some stress in the
system to allow for the continuation of natural processes including occasional tree
mortality. Over time tree mortality is needed to maintain adequate snag densities to
meet wildlife goals.
Existing Information:
· Historical (1920) data on stand conditions in parts of the ownership.
· Intensive forest plots detailing current forest stand conditions (density, sizes, crown
ratios, growth rates, log densities)
· Cruise data detailing tree characteristics (stand types, timber volumes and quality)
· Botany surveys on part of the ownership.
· Detailed geological hazard mapping and analysis
Design Features
Activities Will Be Based On Landscape Location
There are three distinct "landscape locations" in the City forest lands ownership; 1) the dry
steep brushy slopes at the north end (above the big quarry), 2) the large area of variable
slopes with young forest between Granite Street and Reeder Reservoir and 3) the Winburn
parcel which is centrally located in the Watershed with a diversity of vegetation including
some old growth conifer forest. Each of these areas has a different fire history and different
site characteristics. The thinning will occur primarily in the latter two types. The issues and
opportunities are somewhat different in these two areas, so it will be important to consider
them separately.
~"C.....__
Activities Will Be Based On Eco- Type
There are five basic eco-types within the proposed thinning area; pine dominated forest, dry
Douglas fir forest, moist Douglas fir forest, white fir forest and riparian transition zone forest.
For each of these general ecotypes a "desired future condition" will be described to illuminate
what the goal is for the type. We should consider what we want immediately after treatment
is accomplished and then what things will look like in 10 years and then in 20 years.
Desired Future Conditions (Long Term)
Pine Dominated Type: The stands will have relatively open tree spacing (30%-40% canopy
closure) to allow for development of the grass layer, which is native to these sites. Pine will
be a major component (Needs to be defined). Relatively few down logs (e.g. local estimates
of natural levels) . A long term goal of maintaining two large snags per acre. Repeated
entries will be needed to reduce the amount of manzanita that grows on the site. These
stands will take the role that they historically have had of providing breaks in the forest
canopy to slow wildfire.
Dry Douglas Fir Type: The stands will have moderate tree spacing, (40-50%) (60%) canopy
closure, with the emphasis on maintaining full site occupancy and shade tolerant herbaceous
ground species while minimizing the development of shrubby species. Douglas fir, madrone
and black oak will be equally favored with pine left where it occurs. (Needs to be
discussed... the reference notes show that pine and hardwoods were dominant). There
will be relatively few logs (e.g. local estimates of natural levels). The goal will be to maintain 2
large (> 17" DBH) snags per acre.
Moist Douglas Fir and White Fir Type: The stands will have a high level of canopy closure
(50-60%) (70%) and relative density (.5) (.6-.65) with an emphasis on maintaining full site
occupancy and a bit more to be on the conservative side (it is assumed that these sites are
more resilient to beetle damage than the drier types). The number of large down logs will be
higher since it is assumed that those species which rely on large logs will be more abundant
in this type. The goal is to maintain 3 large (>17" DBH) snags per acre.
· Riparian Transition Zones; These are the areas adjacent to streams and draws that
hold significantly more soil moisture than upland areas; these areas are important for
managing water quality and quantity and are important for many species of wildlife.
This zone can be defined using "indicator species" of plants and mosses. In the
watershed, this zone generally extends for 100 feet on southerly aspects and up to
300 feet on northerly aspects adjacent to perennial creeks. On side-draws, this zone
can be 20-50 feet on either side of the draw. The DFC for these areas is essentially
the same as the moist Douglas Fir Type. Here however, we should consider leaving a
high amount (how many?) of large logs and snags. Restoration work is also needed
in some areas.
,-.'~ - -
Coarse Woody Material
This topic still needs considerable discussion and work. We have data on existing coarse woody
material (CWM=large down logs) in the watershed (on Winburn parcel and on Forest Service land).
We recognize that much of our lands (e.g. the 80-100 year old stands) are currently at the low end of
the range of natural variation for CWM. One recommedation is to leave at amounts equivalent to I
standard deviation above average current amounts at most sites and 2 sandard deviations above average
current amounts in Riparian Transition Zones (refer to Frank Betlejewski paper) . Another
recommendation has been to leave the equivalent of 10-20 tons per acre
Additional Design Features
· Encourage the species composition toward pine and hardwoods (shade intolerant/fire
tolerant species). Historical records show that in the past (circa 1920) the City lands
were more open and pine/hardwood dominated. Large pines and hardwoods are able
to withstand fire and maintain a forested watershed, even though they may not
provide late-successional habitat for the northern spotted owl.
· Geologically highly sensitive (Class 1) zones will be left un-thinned to avoid any risk of
slope failure due to management activities.
One way to thin on these sites is to girdle the tree and just let it fall.. providing the
diameter is greater than 6 inches.. . smaller trees just fall over by girdling. You get a
snag, eventually down wood, and as the roots of the girdled tree die off, the adjacent
trees will occupy the sub-surface growing space.. .so there is little loss of soil stability.
· Geologically moderately sensitive (Class 2) areas will be left un-thinned unless there
is high risk of mortality to a significant number of trees in the stand due to excessive
density. In these cases, very light thinning will be done with repeated light thinning in
the future.
Or could girdle trees as above...
· No thinning will be done in actual riparian zones (e.g. roots in the water)
· Planning will include further discussion with wildlife and soils experts to determine the
optimal amount (and sizes) of snags and down woody that is needed for long term soil
health, moisture storage, and wildlife. This needs to include 20 year horizon for
replacement trees.
Methods
Yarding will be done by helicopter (size?).
Haul Routes need to be determined.
Monitoring
This phase of thinning will involve larger trees than previous thinning so there is more
potential for impact to wildlife, arboreal plant species and soils. However the thinning will be
a light thinning, (Is it only thinning? we don't know yet...density management, reduction
of overall tree density may be a better description as it doesn't limit the project to just
1""' --
thinning) and yarding will be by helicopter so these impacts will be minimal (Just what do
we mean by minimal??). Impacts will basically be limited to the trees that are cut and the
"footprint" on the ground where felled trees land.
Monitoring will be designed specifically to track the potential disturbance to ecosystem
elements. The important elements can be narrowed down to; 1) those species which live in
trees and 2) soil and geological processes. Spotted owls are a concern on the Winburn
parcel due to the proximity to three nesting pairs.
Monitoring Elements:
Wildlife: Red tree vole nest trees, existing large cavities in trees (this can be done with
volunteers; individual trees will be marked for protection). Spotted owl habitat (we will
probably need some professional consulting to mesh habitat needs with thinning needs and
write a plan for USF&W consultation (if needed))
We are not required to manage for red tree voles on City lands. . . we can if we want to, but we
have to be very careful as to what responsibilities we are taking on... we should start with our
management guidance, the Oregon Forest Practices Act and then decide if we want to do
anything beyond that
Soils: surface erosion where the tree canopy is significantly reduced (how much is
significant?); slides or accelerated erosion in draws or geologically sensitive areas. (This can
be done by contract with most of it probably accomplished by ReaICorps.)(can we measure
the rate of acceleration?. .how?)
Botany: rare tree dwelling lichens and bryophytes; individual trees would be marked for
protection. (This can be done by volunteers or with a very small capital outlay for an expert
combined with volunteers)
(Again, lets be careful.. .are we required to do this? Or is it something we might want to
do... we should create two lists' a want to do list and a must do list.)
Implementation Monitoring:
Long Term Vegetation Plots: before or immediately after thinning, the existing permanent
vegetation plots will be re-visited and percent cover will be recorded for shrub, grass and
dominant forb species.
Implementation Monitoring: there will be stages of review for interested parties to assess the
progress of the project relative to the stated goals.
Decisions for Commission to make:
There are two sets of decisions to make; the first is on issues such as are outlined above
regarding general policy and design features. The second and more difficult is on issues
such as the balance of silviculture needs and geologic hazards (slope stability) as outlined by
Marty Main.
Additional Info needed
spotted owl management recommendations for Winburn parcel (Fred Way)
logging systems plan (Marty)
Cutting Big Trees?
In general, the goal is to leave the largest healthiest trees and remove the weakest and
smallest trees. This will mostly mean cutting trees in the 20-90 year age class and 6"-18"
diameter size range. However, trees of larger/older size/age classes will be cut during this
thinning if, after careful consideration, it is considered to be important to remove the trees
using for any of the following reasons.
1. The stand is of trees that are all generally large and the stand is too dense to sustain
further growth as evidenced by very slow growth rates and weakening crowns. In these
stands, which are rare, a very conservative thinning of the smallest and/or weakest trees will
be made allowing for development of some mortality (for future snags)
2. Trees that are heavily infected with Douglas fir dwarf mistletoe. In these cases, very large
trees will be left if they are surrounded by an adequate number of madrone, black oak, pine
or white fir to ensure long term stand stability if Douglas fir is reduced. (Light infections or
lower-crown infections will be pruned out)
3. In some cases, clumps of two or more large trees are growing together and may be
stressing each other. In these cases a conservative approach will be taken and trees
removed only if necessary. In general clumps will be considered as single trees with thinning
occurring around them.
4. Hazard Trees along roads or near structures may be considered for removal.
".,......, ",--
Density Management: Second Phase
Very Early Working Draft Proposal #3 1-29-02
(Opinions and preferences are included but do not represent the entire Commission. They are
displayed in italics to provide examples of decisions that need to be made)
Background And Need
The City has been working for the past six years to thin small trees and brush on City-owned forest
lands. This work has focused on thinning small diameter understory trees (less than 7" diameter)~
these have been carefully burned in small piles, This has been sufficient to reduce ladder fuels and
create stable stands in some areas but there are still many stands with very high density of larger trees
that are seriously stressed during drought periods and subject to beetle attack as well as other, slower
stress related mortality.
Based on detailed forest inventories, and silvicultural assessments, it is clear that the City needs to
proceed with a second phase of thinning on its lands in the watershed. Many ofthe forest stands are
precariously overstocked due to the suppression of natural fires in the watershed. The goal of this
second phase of density management is to remove weak trees in understory and mid-layer in order to
attain a stand density that is sustainable over the long term. The focus of this thinning will be on stand
health though there will be an associated fire hazard reduction as a result of reduced tree density and
reduced potential for future tree mortality.
There are many areas of moderate to high geologic hazard where there is a distinct conflict between
the goal of reducing tree density to assure stand health and maintaining maximum tree cover to
guarantee slope stability. Up to this point the Commission has deferred any activity in these areas
(with one exception). The problem with continuing to ignore these areas, however, is that sooner or
later a drought event will lead to accelerated tree mortality and we will lose the trees that are holding
the soil in place. As part of this project we are recommending treatments, which we hope, will resolve
this conflict.
As part of the planning for this next phase of the thinning, we need to clarify what the Desired Future
Condition (DFC) of the various stand types is. This process will be interdisciplinary and look at a
variety of resources essential for maintenance of forest health including healthy soils, stable slopes,
water supply, fire hazard, large dead and down woody materials, and the broad category of protecting
biodiversity, which includes managing for the maintenance of all existing native animal, plant and
fungi species.
Goals
· Reduce forest stand densities to levels that allow the potential for sustaining healthy forest
stands for the long term.
· Maintain "full site occupancy" by trees on most of the forestlands~ maintain the largest trees.
· increase ground layer vegetation including mosses and native grasses.
· Protect and improve riparian transition zone habitat
· Develop an approach for reducing stand density while protecting slope stability in moderately
geologically sensitive areas (hazard 2 zones).
Guiding Principles
As has been the case up to now, the thinning activities will be ecosystem driven (we assume that
financial resources will be available to implement). No trees will be cut simply to add value to a
timber sale. The goal will be to thin just enough to allow remaining trees to survive during drought
periods. The core element of this will be a commitment to carefully detennine which trees are needed
(to be left) in the stand to maintain optimal stand and forest health. Of those, which are cut, only logs
that are in excess of what is optimal for soil development and wildlife needs (balanced with fire hazard
considerations) will be removed to be sold.
· The trees to be cut will mostly be in the age class of 50 -100 years old; this is the age class
that has grown as a result of our fire suppression efforts since 1910. There will be some trees
cut in older age classes if it is detennined to be necessary for the health of the stand. (What we
cut or girdle should not be just a function of age... it could be a low vigor tree (a tree with a
live crown ratio less than 30% (for Douglasfir) or 25% (for pines and hardwoods))
· Thinning Will Be Conservative In Scope: There is a range of stand densities, which are
suitable for healthy stand growth. In this project the upper end of this range will be the target.
In other words we would rather err on the side of leaving too many trees rather than thinning
too many. By this approach we will be leaving some stress in the system to allow for the
continuation of natural processes including occasional tree mortality. Over time tree mortality
is needed to maintain adequate snag densities to meet wildlife goals. (There is a diversity of
opinion on this. Factors to consider include: I) it is unlikely that there will be another
helicopter removal for at least 20 years due to the cost of such an effort, 2) target relative
density should be detennined by stand or by ecotype and will be variable)
Existing Information:
· Historical (1920) data on stand conditions in parts of the ownership.
· Intensive forest plots detailing current forest stand conditions (density, sizes, crown ratios,
growth rates, down log densities)
· Cruise data detailing tree characteristics (stand types, timber volumes and quality)
· Botany surveys on lower part of the ownership.
· Detailed geological hazard mapping and analysis
Design Features
Activities Will Be Planned Based On Landscape Location
There are two distinct "landscape locations" in the City forestlands ownership, which have different
sets of conditions, opportunities and concerns.
The Lower (north) Watershed Area: This area extends from the upper end of Reeder Reservoir to
Granite Street. It is mostly early to mid seral conifer-hardwood forest (60-100 years old) and shrub-
hardwood communities. The area was burned in 190 I and again in 1910 with the northwest portion
burned in 1959. Trees in this area are mostly 8"-22" DBH with some larger trees (24"-30" DBH or
larger) that survived the fires. This area is fairly dry with plant communities in the Douglas fir and
ponderosa pine plant series. (Forested areas are described as landscape units G, Hand K in the Draft
Interface Landscape Unit Map; also see page 3 ofMain(1996)).
Most of the area has had small diameter (<7 inches DBH) understory trees thinned. Of the total area
of 486 acres, approximately 240 acres are under consideration for further thinning (with portions of
units A, BI, B2, E, H and T (83 acres total) additionally potential for removal ofrecentIy dead trees).
Of these 240 acres, 182 acres have been identified as having slope-stability concerns; some of these
areas will involve very difficult management decisions. Other important issues to consider in this area
include Ashland Creek aquatic and riparian transition zone, the water pipeline, water treatment plant,
and access road.
The Winburn Parcel: This area is 160 acres centrally located in the Watershed with a diversity of older
forest types including some classic old growth conifer forest, some "early old-growth" forest (has
some characteristics of "classic old growth" but is still developing), some with scattered large old trees
with dense younger trees under (can't be defined as "old growth" but is still very important) and some
mid-seral forest (100 years old). Most of this forest has high to very high relative density and needs to
be considered for thinning. Some thinning of small diameter trees (<7" DBH) has been done, and will
be continued. We need to consider further thinning of the intermediate size classes (8"-24" DBH) to
ensure continued survival of the large overstory trees. The primary concern in this area is making sure
that the big trees don't die as a result of our management decision to exclude fire for the past 90 years.
Other important issues to consider here include riparian resources on West Fork Ashland Creek and
Weasel Creek, possible occurrence of rare orchids, dwarf mistletoe, slope stability concerns on at least
40 acres of the area, possible occurrence of red tree voles or other unusual wildlife, and foraging
habitat for northern spotted owls.
The late seral condition of this area makes it a controversial area to do any tree cutting. Stand density
reduction in old growth type forest to correct problems stemming from fire exclusion is not a well-
developed science. Careful planning will be needed to determine the best treatment options and
considerable effort will need to be made to share observations and proposals with concerned members
of the community.
Activities Will Be Based On Eco- Type
Each of the two landscape areas has several different eco-types. In the Lower Watershed area are
found: Ponderosa pine series forest, Douglas fir-ponderosa pine forest, moist Douglas fir forest, and
riparian transition zone forest. In the Winburn Parcel are found Moist Douglas fir forest, white fir-
ponderosa pine forest, moist white fir forest and riparian forest. For each of these general ecotypes a
"desired future condition" will be described to illuminate what the goal is for the type. We should
consider what we want immediately after treatment is accomplished and then what things will look
like in 10 years and then in 20 years.
Coarse Woody Material
This topic still needs considerable discussion and work. We have data on existing coarse woody
material (CWM=large down logs) in the watershed (on Winburn parcel and on Forest Service land).
We recognize that much of our lands (e.g. the 80-100 year old stands) are currently at the low end of
the range of natural variation for CWM. One recommendation is to leave at amounts equivalent to 1
standard deviation above average current amounts at most sites and 2 standard deviations above
.',.,_...."...........,...'"""''"'''._,..,. _....,,,_.._..--...---,.~~_.._..,----...........,..... ,....-"
average current amounts in Riparian Transition Zones (refer to Frank Betlejewski paper) . Another
recommendation has been to leave the equivalent of 10-20 tons per acre.
Additional Design Features
· Encourage the species composition toward pine and hardwoods (shade intolerant/fire tolerant
species). Historical records show that in the past (circa J 920) the City lands were more open
and pine/hardwood dominated. Large pines and hardwoods are able to withstand fire and
maintain a forested watershed, even though they may not provide late-successional habitat for
the northern spotted owl. (Marty-We tend to lump hardwoods together but madrone and black
oak are quite different in their ecological roles and functions. We particularly prioritize
retention of black oak (and white oak where it occurs). I believe that a reference condition of
J 50 years ago would have found more oaks and pine and less madrone- two intense
disturbances back-to-back (i. e. J 90 J, J 9 J 0) would greatly favor increases in madrone.
Reference condition is great for indicating that change in veg occurs over time; we have to be
careful about suggesting that the veg of anyone reference condition is the type we want to
shoot for,
.
· Geologically highly sensitive (Class J) zones will be left un-thinned to avoid any risk of slope
failure due to management activities.
One way to thin on these sites is to girdle the tree and just let it fall... providing the diameter is
greater than 6 inches... smaller trees just fall over by girdling. You get a snag, eventually down
wood, and as the roots of the girdled tree die off the adjacent trees will occupy the sub-surface
growing space... so there is little loss ofsoil stability. (Girdling could encourage development
of bark beetle infestation, not a particularly exciting proposition) (Also increased fire hazard)
Excessive stand densities in geohazard zone J (e.g. the Barranca Unit)- isn't this even a higher
priority for stand density reduction of some kind? How do we propose that?
· Geologically moderately sensitive (Class 2) areas will be left un-thinned unless there is high
risk of mortality to a significant number of trees in the stand due to excessive
density. In these cases, very light thinning will be done with repeated light thinning in the
future.
Or could girdle trees as above..,
· Tree selection will be determined by a combination of variables, including crown ratio, basal
area, radial growth and species.
· No thinning will be done in actual riparian zones (e.g. roots in the water).
· Planning will include further discussion with wildlife and soils experts to determine the
optimal amount (and sizes) of snags and down woody that is needed for long term soil health,
moisture storage, and wildlife. This needs to include 20-year horizon for replacement snags.
Methods
Trees should be marked prior to cutting,
Yarding will be done by helicopter.
"._,=~,~-,,-~, ,---'."~---~,"_.,---_..-,---~--" ,~~..,..." ..----
Haul Routes need to be determined.
Is there potential for a log sort-yard to allow for specialized marketing of small diameter logs of
various qualities?
Monitoring
This phase of thinning will involve larger trees than previous thinning so there is more potential for
impact to wildlife, arboreal plant species and soils. However the thinning will be a light thinning, (Is
it only thinning? we don't know yet...density management, reduction of overall tree density may
be a better description as it doesn't limit the project to just thinning) and yarding will be by
helicopter so these impacts will be minimal (Just what do we mean by minimal??). Impacts will
basically be limited to the trees that are cut and the "footprint" on the ground where felled trees land.
Monitoring will be designed specifically to track the potential disturbance to ecosystem elements. The
important elements can be narrowed down to; 1) those species which live in trees and 2) soil and
geological processes. Spotted owls are a concern on the Winburn parcel due to the proximity to three
nesting pairs.
Monitoring Elements:
Wildl~re: Red tree vole or flying squirrel nest trees, existing large cavities in trees (this can be done
with volunteers; individual trees will be markedfor protection). Spotted owl habitat (we will probably
need some professional consulting to mesh habitat needs with thinning needs and write a plan for
USF & W consultation (if needed)) .Fred Way says that Ashland Watershed is outside the range of the
red tree vole- any new info on that?
We are not required to manage for red tree voles on City lands.., we can if we want to, but we have to
be very careful as to what responsibilities we are taking on,., we should start with our management
guidance, the Oregon Forest Practices Act and then decide ifwe want to do anything beyond that
Soils: surface erosion where the tree canopy is significantly reduced (how much is Significant?);
slides or accelerated erosion in draws or geologically sensitive areas. (This can be done by contract
with most of it probably accomplished by ReaICorps.)(can we measure the rate of
acceleration?. how?)
Botany: rare tree dwelling lichens and bryophytes; individual trees could be marked for protection.
(This can be done by volunteers or with a very small capital outlay for an expert combined with
volunteers)
(Again, lets be careful... are we required to do this? Or is it something we might want to do... we
should create two lists' a want to do list and a must do list.)
Implementation Monitoring:
Long Term Vegetation Plots: before or immediately after thinning, the existing permanent vegetation
plots will be re-visited and percent cover will be recorded for shrub, grass and dominant forb species.
There will be stages of review for interested parties to assess the progress of the project relative to the
stated goals.
_ -_,..-.,~..........--",_"'_'"<., e_~."'""",,_,,"~"""'''__'' ".'u___.",.. ,_,,_.
Decisions for Commission to make:
There are two sets of decisions to make; the first is on issues such as are outlined above regarding
general policy and design features, The second and more difficult is on issues such as the balance of
silviculture needs and geologic hazards (slope stability) as outlined by Marty Main.
Additional Info needed
spotted owl management recommendations for Winburn parcel (Fred Way)
logging systems plan (Marty)
wildlife features inventory
microflora (lichen,moss) inventories
Current Conditions References
Riparian conditions
Geology/soils conditions (Bill Hicks,..)
Landscape Unit Descriptions (See Main (in pub.) Report on Forest Interface: Landscape Unit
Inventory)
Stand conditions/ Unit Prescriptions (Main 1996, 1998, 1999)
Snags/CWM (Organon monitoring plots)
Desired Future Conditions (Long Term) For Lower Watershed Area
Pine Dominated Type (Landscape Unit D)
This type occurs on upper slope and ridgeline positions and often are currently dominated by white leaf
manzanita. The stands of this type on City ownership have already been treated (manzanita removed)
and are on a trajectory toward this DFC except that there is a general lack of grass layer (planting
needed)
The stands will have relatively open tree spacing (30%-40% canopy closure) to allow for development
of the grass layer, which is native to these sites, Pine will be a major component (Needs to be defined)
along with black oak and madrone. Relatively few down logs (e.g. local estimates of natural levels) . A
long term goal of maintaining an average of one large snag per acre. Repeated entries will be needed
to reduce the amount of manzanita that grows on the site. These stands will take the role that they
historically have had of providing breaks in the forest canopy to slow wildfire.
Douglas Fir-Ponderosa Pine Type (Landscape Unit G)
This type is generally on the upper 2/3 of south and west aspects with a mix of pine, Douglas fir,
madrone and black oak on fairly dry sites, mostly with stable slopes. These are good area to manage
for pine and hardwoods.
These stands will have a mix of tree species with ponderosa pine, sugar pine and black oak especially
favored. Tree spacing will be moderate (40-50% canopy closure) to allow for development of a stable
ground layer including a grass component (Western fescue, Idaho fescue, California fescue) and shade
<.. "'."......,.......--'-,."',.. '..........~~.-~,~".<-~~",'- .--'"--,...'.--,.--...
intolerant herbaceous species (such as the rare species Horkelia hendersonii which occurs on these
sites). There will be relatively few logs (e.g. mean local estimates of natural levels). The goal will be to
maintain 2 large (> 17" DBH) snags per acre.
Dry Douglas fir Type (Landscape Units Hand J)
This type occurs on north and west aspects and lower 1/3 of some south slopes. There currently is a
mix of Douglas fir and madrone with some ponderosa pine and black oak:. Many areas are steep with
slope stability concerns.
The stands will have moderate tree spacing, (60%-70%) canopy closure, with the emphasis on
maintainingfull site occupancy and shade tolerant herbaceous ground species while minimizing the
development of shrubby species, Douglas fir, madrone and black oak will be equally favored with pine
left where it occurs. (Needs to be discussed... the reference notes show that pine and hardwoods
were dominant). There will be a moderate level of Coarse Woody Material (e.g. 1 SD above mean
local estimates of natural levels), The goal will be to maintain 2 large (> 17" DBH) snags per acre,
Moist Douglas Fir Type(Part of Landscape Unit J):
This type occurs on very steep northerly aspects in the southern half of the area. Douglas fir is
dominant with some madrone and ponderosa pine present (but at a competitive disadvantage). Slope
stability is usually an issue,
The stands will have a high level of canopy closure (70%+) and relative density (.5) (.6-.65) with an
emphasis on maintaining full site occupancy and a bit more to be on the conservative side (it is
assumed that these sites are more resilient to beetle damage than the drier types). The number of large
down logs will be higher since it is assumed that those species which rely on large logs will be more
abundant in this type and slope stability is a primary concern. The goal is to maintain 3 large (> 17"
DBH) snags per acre.
Riparian Transition Zones: These are the areas adjacent to streams and draws that hold significantly
more soil moisture than upland areas; these areas are typically very steep with unstable soils and are
important for managing water quality and quantity; these areas are also important for many species of
wildlife. This zone can be defined using "indicator species" of plants and mosses. In the watershed,
this zone generally extends for 100 feet on southerly aspects and up to 300 feet on northerly aspects
adjacent to perennial creeks, On side-draws, this zone can extend 20-50 feet from the bottom of the
draw on southerly aspects and 50-100 feet on northerly aspects.
The DFC for these areas is essentially the same as the moist Douglas Fir Type. Here however, we
should consider leaving a high amount (how many?) of large logs and snags. Restoration work is also
needed in some areas,
Cutting Big Trees?
In general, the goal is to leave the largest healthiest trees and remove the weakest and smallest trees.
This will mostly mean cutting trees in the 20-90 year age class and 6"-18" diameter size range,
However, trees of larger/older size/age classes will be cut during this thinning if, after careful
consideration, it is considered to be important to remove the trees using for any of the following
reasons.
1. The stand is of trees that are all generally large and the stand is too dense to sustain further growth
as evidenced by very slow growth rates and weakening crowns. In these stands, which are rare, a very
conservative thinning of the smallest and/or weakest trees will be made allowing for development of
some mortality (for future snags)
2. Trees that are heavily infected with Douglas fir dwarf mistletoe. In these cases, very large trees will
be left if they are surrounded by an adequate number of madrone, black oak, pine or white fir to ensure
long term stand stability if Douglas fir is reduced. (Light infections or lower-crown infections will be
pruned out)
3. In some cases, clumps of two or more large trees are growing together and may be stressing each
other. In these cases a conservative approach will be taken and trees removed only ifnecessary. In
general clumps will be considered as single trees with thinning occurring around them.
4. Hazard Trees along roads or near structures may be considered for removal.
-,.~.~...,_.....".....--"'-'~.."'--_...._--""-''''''""' <",~-..,~-", '-'.-'"'...',',-...-,
Very Early Draft Proposed Density Management Areas: Lower Watershed Area
Estimate Of Acres Of Slope Stability Concerns
Stand Density
Stable Slope
Slopes Stability
Concerns
Possibly
Remove some
Dead and
Dying Trees
A
Bl
B2,3,4
B5,6
C
D
E
F
G
H
J
K
L
M
N
P
Q
R
S
T
U
V
Totals
20
8
5
5
above Morton S1. housing development
above Morton S1. housing development
part of B2 is above housing developments
12
28
4
6
7
33
10
21
27
23
25
14
40
31
probably no further thinning
Previous high mortality already removed
Dry sites that had dense manzanita
burned in 1959
existing fuel break
some older trees on this unit; mistletoe problem
perched above housing development
burned in 1959
burned in 1959
54
182
83
~'"^'..'''-'~-'"'''''----'-'-'''^''-~~'''' .---..-' ,.. ......_'.
City Forest Lands Density Management: Second Phase
Proposed Working Draft Proposal #4 3-05-02
Background And Purpose
The City has been working for the past six years to thin small trees and brush on City-owned forest
lands. This work has focused on thinning small diameter understory trees (less than 7" diameter);
these have been carefully burned in small piles. This has been sufficient to reduce ladder fuels and
create stable stands in some areas but there are still many stands with very high density of larger tre(:s
that are seriously stressed during drought periods and subject to beetle attack as well as other, slower
stress related mortality.
Based on detailed forest inventories, and silvicultural assessments, it is clear that the City needs to
proceed with a second phase of thinning on its lands in the watershed. Many of the forest stands are
overstocked due to the suppression of natural fires in the watershed. The goal of this second phase of
density management is to remove weak trees in understory and mid-layer in order to attain a stand
density that is sustainable over the long term. The focus will be on forest stand health though there
will be an associated fire hazard reduction as a result of reduced tree density and reduced potential fix
future fuels buildup from tree mortality.
There are many areas of moderate to high geologic hazard where there is a distinct conflict between
the goal of reducing tree density to assure stand health and maintaining maximum tree cover to
guarantee slope stability. Up to this point the Commission has deferred any activity in these areas (with
one exception). The problem with continuing to ignore these areas, however, is that sooner or later a
drought event will lead to accelerated tree mortality and we will lose the trees that are holding the soil
in place. As part of this project we are recommending treatments, which we hope, will resolve this
conflict.
As part of the planning for this next phase of the thinning, we will clarify what the Desired Future
Condition (DFC) of the various stand types is. This process will be interdisciplinary and look at a
variety of resources essential for maintenance of forest health including healthy soils, stable slopes,
water supply, fire hazard, large dead and down woody materials, and the broad category of protecting
biodiversity, which includes managing for the maintenance of all existing native animal, plant and
fungi species.
Goals
.
Reduce forest stand densities to levels that allow the potential for sustaining healthy forest
stands for the long term by thinning understory and mid-layer trees.
Maintain structures, features and processes critical to functioning late seral reserves such as
large trees, snags, down logs, soil structure and organisms, etc.
Initiate management activities that will, over time, return wildfire hazard and fuel levels to pre-
settler levels and ultimately restore a disturbance regime that more closely emulates the historic
range of variability.
To minimize the need for continued intervention in the landscape to eventually allow natural
fire cycles to occur under the concept of a "natural fire plan" for the entire watershed.
1
.
.
.
~"'-''''~-''-
· Protect and improve riparian transition zone habitat.
· Improve soil texture in upper soil profiles to increase water holding capacity and surface soil
stability; maintain stability of deeper soil profiles,
· Increase ground layer vegetation including mosses, native grasses and low shrubs to provide
stability to the surface soils.
· Develop an approach for reducing stand density while protecting slope stability in moderately
geologically sensitive areas (hazard 2 zones).
· Maintain landscape level diversity to emulate pre-settler era patterns.
Guiding Principles
· We acknowledge the complexity and uncertainty inherent in ecosystem management and that
we do not completely know how to manage the interlocking ecological functions of a healthy
watershed.
· Activities will be guided by recommendations based on the thorough site evaluation that has
been conducted by experts on geology, silviculture, botany, wildlife and other resources as well
as expertise developed over the past six years of work. Ongoing monitoring will be developed
to allow for adaptive management.
· As has been the case up to now, stand density reduction will be ecosystem driven. The project
will be planned to address forest stand health needs providing timber only as a by-product of
primary restoration objectives. There will be a commitment to carefully determine which trees
are needed (to be left) in the stand to maintain optimal stand and forest health. Ofthose, which
are cut, only logs that are in excess of what is needed for soil development and wildlife needs
(balanced with fire hazard considerations) will be removed to be sold. No trees will be removed
simply to add value to a timber sale,
· Maintain "full site occupancy" by trees on most ofthe forestlands; maintain the largest trees.
· The trees to be cut will mostly be in the age class of 50 -100 years old; this is the age class that
has grown as a result of our fire suppression efforts since 1910. There will be some trees cut in
older age classes if it is determined to be necessary for the health of the stand.
· Thinning will be conservative in scope: while target relative density should be determined by
stand or by ecotype and will be variable, where there is uncertainty in the models (such as in
older stands) we want to err on the side of leaving too many trees rather than removing too
many. The goal in most of the stands is to encourage successional development by releasing
overstory trees and removing elements of early seral stages such as small suppressed
understory trees.
Existing Information:
· Historical (1920) data on stand conditions in parts of the ownership.
· Intensive forest plots detailing current forest stand conditions (density, sizes, crown ratios,
growth rates, down log densities)
· Stand conditions/ Unit Prescriptions (Main 1996, 1998, 1999)
· Cruise data detailing tree characteristics (stand types, timber volumes and quality) (Main 1999)
· Botany surveys on lower part of the ownership,
· Detailed geological hazard mapping and analysis (Bill Hicks...)
· Snags/CWM (Organon monitoring plots)
2
· General riparian conditions survey (USFS)
· Landscape Unit Descriptions (Main (in pub.) Report on Forest Interface: Landscape Unit
Inventory)
· Upper Bear Creek Watershed Analysis (USFS)
Design Features
Activities Will Be Planned Based On Location
There are two distinct "landscape locations" in the City forestlands ownership, which have different
sets of conditions, opportunities and concerns.
The Lower (north) Watershed Area: This area extends from the upper end of Reeder Reservoir to
Granite Street. It is mostly early to mid seral conifer-hardwood forest (60-100 years old) and shrub-
hardwood communities. The area was burned in 1901 and again in 1910 with the northwest portion
burned in 1959. Trees in this area are mostly 8"-22" DBH with some larger trees (24"-30" DBH or
larger) that survived the fires. This area is fairly dry with plant communities in the Douglas fir and
ponderosa pine plant series. (Forested areas are described as landscape units G, H and K in the Draft
Interface Landscape Unit Map; also see page 3 ofMain(1996)),
Most ofthe area (250 acres) has had small diameter (<7 inches DBH) understory trees thinned. Of the
total area of 486 acres, approximately 240 acres are under consideration for further thinning (with
portions of units A, B I, B2, E, H and T (83 acres total) additionally potential for removal of recently
dead trees or thinning of small patches). Of these 240 acres, 182 acres have been identified as having
slope-stability concerns or potential risk to property or the water system infrastructure; some of these
areas will involve very difficult management decisions. Other important issues to consider in this area
include Ashland Creek aquatic and riparian transition zone, the water pipeline, water treatment plant,
and access road.
The Winburn Parcel: This area is 160 acres centrally located in the Watershed with a diversity of
older forest types including some classic old growth conifer forest, some "early old-growth" forest (has
some characteristics of "classic old growth" but is still developing), some with scattered large old trees
with dense younger trees under (can't be defined as "old growth" but is still very important) and some
mid-seral forest (100 years old). Most of this forest has high to very high relative density and needs to
be considered for thinning. Some thinning of small diameter trees (<7" DB H) has been done, and will
be continued. We need to consider further thinning of the intermediate size classes (8"-24" DBH) to
ensure continued survival of the large overstory trees. The primary concern in this area is making sure
that the big trees don't die as a result of our management decision to exclude fire for the past 90 years.
Other important issues to consider here include riparian resources on West Fork Ashland Creek and
Weasel Creek, possible occurrence of rare orchids, dwarf mistletoe, slope stability concerns on at least
40 acres of the area, possible occurrence of red tree voles or other unusual wildlife, and foraging
habitat for northern spotted owls.
The late seral condition of this area makes it a controversial area to do any tree cutting. Stand density
reduction in old growth type forest to correct problems stemming from fire exclusion is not a well-
developed science. Careful planning will be needed to determine the best treatment options and
3
--,-,- ~
considerable effort will need to be made to share observations and proposals with concerned membt::rs
of the community.
Activities Will Be Based On Eco-Type As Designated By Landscape Unit
Each of the two locations has several different eco-types, In the Lower Watershed area are found:
Ponderosa pine series forest, Douglas fir-ponderosa pine forest, moist Douglas fir forest, and riparian
transition zone forest. In the Winburn Parcel are found moist Douglas fir forest, white fir-ponderosa
pine forest, moist white fir forest and riparian forest. One way to describe these eco-types is as
"Landscape Units" (Main in pub.). For each of these landscape units a "desired future condition" will
be described to illuminate what the goal is for the type, We should consider what we want immediately
after treatment is accomplished and then what things will look like in 10 years and then in 20 years.
Coarse Woody Material
The general goal is to utilize large down logs to stabilize surface soils, increase organic content in soils
over the long term and provide habitat for the many organisms which depend on logs. We have data on
existing coarse woody material (CWM=large down logs) in the watershed (on Winburn parcel and on
Forest Service land). We recognize that much of our lands (e,g. the 80-100 year old stands) are
currently at the low end of the range of natural variation for CWM. One recommendation is to leave
amounts equivalent to I standard deviation above average current amounts at most sites and 2 standard
deviations above average current amounts in Riparian Transition Zones (refer to Frank Betlejewski
paper) . Another recommendation has been to leave the equivalent of 10-20 tons per acre.
Wildlife
The project will be designed so that there will be very little negative impact and more likely positive
impact to animal species which currently utilize the area, including spotted owls and arboreal
mammals. The thinning of understory and mid-layer canopy layers allows for easier movement for
owls and forest hawks. During project layout and tree marking, trees that have indications of nest sites
or large cavities will be retained. Additional logs will be added to the forest floor as needed. The
process of snag development through tree mortality is expected to continue after the density reduction
(though significantly slower). Over time, tree mortality is needed to maintain adequate snag densities
to meet wildlife goals.
Additional Design Features
· We want to manage for a diversity of tree species (e.g. more open canopy; lower relative
density) on sites which are currently supporting healthy hardwoods and pine and are on stable
slope positions. In all locations we want to retain black oak and white oak.
· Geologically sensitive zones with high silvicultural risk (high density) will be assessed on a
case by case basis and thinned very carefully to ensure slope stability.
· Tree selection will be determined by a combination of variables, including crown ratio, basal
area, radial growth and species.
· No thinning will be done in actual riparian zones (e.g. roots in the water).
4
· Planning will include further discussion with wildlife and soils experts to determine the
amount (and sizes) of snags and down woody that is needed for long term soil health, moisture
storage, and wildlife.
Methods
Trees should be marked prior to cutting.
Yarding will be done by helicopter.
Haul Routes need to be determined; it is likely that most of the loads will travel down Granite Street
and run through town on East Main to Siskiyou.
Is there potential for contracting for a log sort-yard to allow for specialized marketing of small
diameter logs of various qualities?
Monitoring
This phase of density management will involve larger trees than previous thinning so there is more
potential for impact to wildlife, arboreal plant species and soils. It is expected that over time there will
be changes in understory vegetation and tree growth. However, the proposed treatment will generally
be a light thinning, and yarding will be by helicopter so these impacts should be within a tolerable
range for the elements. Immediate impacts will basically be limited to the trees that are cut, the
"footprint" on the ground where felled trees land. Longer term effects will develop by opening up the
canopy to varying degrees and reducing root structure in the deeper soil profiles.
Monitoring will be designed specifically to:
I) track the changes in ecosystem elements that are likely to change as a result of the density
reduction
2) compare effects of treatments at different locations
3) ensure that the desired effects are produced
The important elements to consider in relation to this project can be narrowed down to; I) those
species which live in trees, 2) soil and geological processes, 3)ground layer vegetation,
Monitoring Elements:
Wildlife: Design features should ensure that there will be little impact to wildlife species so no
monitoring is proposed.
Soils: surface erosion where the tree canopy is significantly reduced (how much is significant?); slides
or accelerated erosion in draws or geologically sensitive areas. (This can be done by contract with
most of it probably accomplished by ReaICorps.)(can we measure the rate of acceleration?... how?)
Botany: Design features should ensure that there will be little impact to plant, moss, lichen and
liverwort species so no species-specific monitoring is proposed. There will be monitoring of ground
layer vegetation on fixed plots.
Implementation Monitoring:
5
>>~'-'~'-"'^~----' ~
Long Term Vegetation Plots: before or immediately after thinning, the existing permanent vegetation
plots will be re-visited and percent cover will be recorded for shrub, grass and dominant forb species.
There will be stages of review for interested parties to assess the progress of the project relative to the
stated goals.
Additional Info needed
spotted owl management recommendations for Winburn parcel (Fred Way)
logging systems plan (Marty)
wildlife features inventory (small contract?)
microflora (lichen,moss) inventories (volunteer with stipend for "expert")
Economics
Desired Future Conditions (Long Term) For Lower Watershed Area
Pine Dominated Type (Landscape Unit D)
This type occurs on upper slope and ridgeline positions and often are currently dominated by white leaf
manzanita. The stands of this type on City ownership have already been treated (manzanita removed)
and are on a trajectory toward this DFC except that there is a general lack of grass layer (planting
needed)
The stands will have relatively open tree spacing (30%-40% canopy closure) to allow for development
of the grass layer, which is native to these sites. Pine will be a major component (Needs to be defined)
along with black oak and madrone. Relatively few down logs (e.g. local estimates of natural levels) A
long term goal of maintaining an average of one large snag per acre. Repeated entries will be needed
to reduce the amount of manzanita that grows on the site. These stands will take the role that they
historically have had of providing breaks in the forest canopy to slow wildfire.
Douglas Fir-Ponderosa Pine Type (Landscape Unit G)
This type is generally on the upper 2/3 of south and west aspects with a mix of pine, Douglas fir,
madrone and black oak on fairly dry sites, mostly with stable slopes. These are good area to manage
for pine and hardwoods.
These stands will have a mix of tree species with ponderosa pine, sugar pine and black oak especially
favored. Tree spacing will be moderate (40-50% canopy closure) to allow for development of a stable
ground layer including a grass component (Western fescue, Idaho fescue, California fescue) and shade
intolerant herbaceous species (such as the rare species Horkelia hendersonii which occurs on these
sites). There will be relatively few logs (e.g. mean local estimates of natural levels). The goal will be to
maintain 2 large (> 17" DBH) snags per acre.
6
Dry Douglas fir Type (Landscape Units Hand J)
This type occurs on north and west aspects and lower 1/3 of some south slopes. There currently is a
mix of Douglas fir and madrone with some ponderosa pine and black oak. Many areas are steep with
slope stability concerns.
The stands will have moderate tree spacing, (60%-70%) canopy closure, with the emphasis on
maintainingfull site occupancy and shade tolerant herbaceous ground species while minimizing the
development of shrubby species. Douglas fir, madrone and black oak will be equally favored with pine
left where it occurs. (Needs to be discussed... the reference notes show that pine and hardwoods
were dominant). There will be a moderate level of Coarse Woody Material (e.g. 1 SD above mean
local estimates of natural levels). The goal will be to maintain 2 large (> 17" DBH) snags per acre.
Moist Douglas Fir Type(Part of Landscape Unit J):
This type occurs on very steep northerly aspects in the southern half ofthe area. Douglas fir is
dominant with some madrone and ponderosa pine present (but at a competitive disadvantage). Slope
stability is usually an issue.
The stands will have a high level of canopy closure (70%+) and relative density (.5) (.6-.65) with an
emphasis on maintainingfull site occupancy and a bit more to be on the conservative side (it is
assumed that these sites are more resilient to beetle damage than the drier types). The number of large
down logs will be higher since it is assumed that those species which rely on large logs will be more
abundant in this type and slope stability is a primary concern. The goal is to maintain 3 large (> 17"
DBH) snags per acre.
Riparian Transition Zones: These are the areas adjacent to streams and draws that hold significantly
more soil moisture than upland areas; these areas are typically very steep with unstable soils and are
important for managing water quality and quantity; these areas are also important for many species of
wildlife. This zone can be defined using "indicator species" of plants and mosses. In the watershed, this
zone generally extends for 100 feet on southerly aspects and up to 300 feet on northerly aspects
adjacent to perennial creeks. On side-draws, this zone can extend 20-50 feet from the bottom of the
draw on southerly aspects and 50-100 feet on northerly aspects.
The DFC for these areas is essentially the same as the moist Douglas Fir Type, Here however, we
should consider leaving a high amount (how many?) of large logs and snags. Restoration work is also
needed in some areas.
7
,--- ""!'
Cutting Big Trees?
Still Very Early Draft
We all agree that large trees are of primary importance in the watershed ecosystems. There is a range of
opinion, though, on what size classes are important and whether any large trees should be cut during a
project like this.
In addressing the question of "what is a big tree?" we believe that we need to think in relative terms on
a site-by-site basis. In a stand that is all 6"-12" DBH trees, a 16" DBH tree is a big tree while in an old
growth stand a 24" tree may be considered to be relatively insignificant. In general we can consider the
upper size class percentiles (say the upper 20%) of trees in a stand to be significant in terms of the
developing overstory. The degree of significance then can be assessed in terms of the number oftrees
in the stand in those larger size classes. When we get into the "old growth" size classes (over 30" DBH,
generally over 150 years old) we recognize that there are important ecosystem contributions beyond
the visible structure of the tree.
In general, the goal is to leave the largest healthiest trees and remove the weakest and smallest trees.
This will mostly mean cutting trees in the 20-90 year age class and 6"-18" diameter size range.
However, trees oflarger/older size/age classes will be cut during this thinning if, after careful
consideration, it is considered to be important to remove the trees using for any of the following
reasons.
I. The stand is of trees that are all generally large and the stand is too dense to sustain further growth as
evidenced by very slow growth rates and weakening crowns. In these stands, which are rare, a very
conservative thinning of the smallest and/or weakest trees will be made allowing for development of
some mortality (for future snags)
2. Trees that are heavily infected with Douglas fir dwarf mistletoe. In these cases, very large trees will
be left if they are surrounded by an adequate number ofmadrone, black oak, pine or white fir to ensure
long term stand stability if Douglas fir is reduced. (Light infections or lower-crown infections will be
pruned out)
3. In some cases, clumps of two or more large trees are growing together and may be stressing each
other. In these cases a conservative approach will be taken and trees removed only if necessary. In
general clumps will be considered as single trees with thinning occurring around them.
4. Hazard Trees along roads or near structures may be considered for removal.
8
.,~'.....~
City Forest Lands Density Mana2ement: Second Phase
Proposed Working Draft Proposal #7 05/17/2002 - 7/03/2002
(Comments from the May 29th meeting, Kerwin's wildlife section, the addition of Marty Main's
Comments and Betlejewski's dead wood text in italics)
Background and Purpose
The City has been working for the past six years to thin small trees and brush on City-owned forest
lands. This work has focused on thinning small diameter understory trees (less than 7" diameter)
which have been carefully burned in small piles. This work has been sufficient to reduce ladder fuels
and create stable stands in some areas, but there are still many stands with a very high density of trees
(greater than 7 inches in diameter) that are seriously stressed during drought periods and subject to
beetle attack as well as other, slower stress-related mortality such as mistletoe,
Based on detailed forest inventories and silvicultural assessments, it is clear that the City needs to
proceed with a second phase of thinning on its lands in the watershed. Many of the forest stands are
overstocked due to the suppression of natural fires in the watershed. The goal of this second phase of
density management is to remove low vigor trees in the understory and middle canopy in order to
attain a stand density that is sustainable over the long term. The focus will be on forest stand health
though there will be an associated fire hazard reduction as a result of reduced tree density, shift in
species composition favoring shade intolerant, fire tolerant species, and reduced potential for future
fuels buildup from tree mortality.
There are many areas of moderate to high geologic hazard where there is a distinct conflict between the
goal of reducing tree density to assure stand health and maintaining enough tree cover to guarantee
slope stability. Up to this point the Commission has deferred any activity in these areas (with one
exception). The problem with continuing to ignore these areas, however, is that sooner or later a
drought event will lead to accelerated tree mortality and we will lose the trees that are holding the soil
in place. As part of this project we are recommending treatments we believe will resolve this dilemma.
As part of the planning for this next phase of the density management, the commission intends to
clarify the Desired Future Condition (DFC) of the various stand types. This process will be
interdisciplinary and look at a variety of resources essential for the maintenance of forest health
including healthy soils, stable slopes, water supply, fire hazard, dead and down woody materials, and
the broad category of protecting biodiversity, which includes managing for existing native animal,
plant and fungi species.
Goals of Vegetation Manipulation
· Reduce forest stand densities to levels that allow the potential for sustaining healthy forest
stands for the long term by thinning understory and middle canopy trees.
· Maintain structures, features and processes critical to the functioning of mature forests such as
large trees, snags, down logs, soil structure, etc.
----" ,-, -"",
· Initiate management activities that will, over time, significantly reduce the likelihood of large
scale, high intensity wildfire and ultimately restore a disturbance regime that more closely
emulates the historic range of variability (frequent, small scale, low intensity fires as opposed to
infrequent, high intensity fires). This will not be accomplished with a single management
action and may take years or decades to complete.
· Minimize the need for continued intervention in the landscape to eventually allow natural fire
cycles to occur under the concept of a "natural fire plan" for the entire watershed.
· Protect and improve riparian transition zone habitat. (i,e. Those areas where the vegetation
shows a distinctly different plant community compared to the adjacent uplands. This plant
community is a result of increased moisture availability and proximity to the stream channel.)
Increase effective ground layer vegetation including woody debris, mosses, native grasses and
low shrubs to provide stability to the surface soils.
· Develop an approach for reducing stand density while protecting slope stability in moderately
geologically sensitive areas (Hazard 2 zones).
· Encourage landscape level diversity by preserving appropriate species
diversity in each landscape unit; species diversity will be based on
landscape unit ecotype.
Guiding Principles
· We acknowledge the complexity and uncertainty inherent in ecosystem management and that
we do not completely understand how to manage the interlocking ecological functions of a
healthy watershed; however, we do have enough information to proceed.
· Activities will be guided by recommendations based on the thorough site evaluations by
individuals with expertise in geology, forest ecology, fire ecology, silviculture, botany, wildlife,
soils, ftsheries and other resources as well as drawing from experience gained over the past six
years of work. Monitoring protocols will be developed to allow for adaptive management.
· No trees will be removed simply to add value to a timber sale. Stand density reduction will be
ecosystem driven. The project will be planned to address forest stand health needs providing
timber and other forest commodities only as a by-product of restoration objectives. What is left
behind is more important than what is removed. Trees will be made available for harvest after
retention trees (including those necessary for standing snags and down logs) are identified,
· The trees to be removed will mostly be in the age class of 50 -100 years old; this is the age
class that has grown as a result of our fire suppression efforts since 1910. There will be some
2
trees cut in older age classes as removal of the 50 to 100 year age class does not reduce stand
densities to desired levels,
· By minimizing the percent removal oftrees (e.g. percent basal area) in any stand or unit on
City property, negative impacts to existing resource values can be greatly minimized. Pre-
settlement basal areas were significantly lower than currently exists post treatment densities
will exceed those of pre-settlement stands.
Trees to be removed shall be driven by ecologically-based stand management goals, and desired
stand densities, structures, and compositions of those stands, rather than by the specific diameter of
age class delineation. Nonetheless, with rare exception, it is the intent of this stand density
reduction project to increase the average post-harvest age and diameter of stands entered. In other
words, management at this time is designed to protect and/or promote increasingly larger diameters
/ older age classes of conifers and hardwoods on the City ownership. Exceptions to this trend
should be clearly identified, mapped and presented with a detailed explanation. It is believed that
trending towards more mature forests will most effectively help promote accomplishment of goals
and objectives identified by the City.
Existing Information:
· Historical (1920) data on stand conditions in parts of the ownership.
· Fire history (after 1700 to 1900) from the Applegate Valley.
Permanent forest inventory plots detailing current forest stand conditions [density, sizes, crown
ratios, growth rates, down log densities (currently only at Winburn)]
· Stand conditions/ Unit Prescriptions (Main 1996, 1998, 1999) if we are going to cite
something, we need to have it in a reference section at the back of the document
· Cruise data detailing tree characteristics (stand types, timber volumes and quality) (Main 1999)
same comment for citation (This information is important because we will then be able to
project what percent of total volume is removed in any harvest.)
· Botany surveys on the lower part of the ownership. Citation?
· Detailed geological hazard mapping and analysis (Bill Hicks..,) Citation?
· Organon monitoring plots
· General riparian conditions survey (USFS) Citation?
3
."_.........-~---
Landscape unit descriptions (Main, "Report on Forest Interface: Landscape Unit Inventory")
Shift to reference section (I believe landscape units would be appropriate to use on the lower
City ownership.)
· Upper Bear Creek Watershed Analysis (USFS) Citation?
Design Features
Activities will be planned based on location. There are two distinct "landscape locations" in the
City forestlands ownership with different sets of conditions, opportunities and concerns.
The Lower (north) Watershed Area: This area extends from the upper end of Reeder Reservoir
to Granite Street. It is mostly early to mid seral conifer-hardwood forest (60-100 years old) and
shrub-hardwood communities. None of these areas have reached mature conditions. Portions of
the area were burned in 1901 and again in 1910 with the northwest portion burning a third time in
1959. Trees in this area are mostly 8"-22" DBH with rare larger trees (24"-30" DBH or larger) that
survived the fires. This area is fairly dry with plant communities in the Douglas fir and ponderosa
pine plant series. (Forested areas are described as landscape units G, H and K in the Draft Interface
Landscape Unit Map; also see page 3 of Main, 1996),
Most of the area (250 acres) has had small diameter (<7 inches DB H) understory trees thinned. Of
the total area of 486 acres, approximately 240 acres are under consideration for further thinning
[with portions of Units A, B I, B2, E, Hand T (83 acres total) having additional potential for
thinning or mortality salvage (removal of dead trees)]. (I did not get to check acreages and/or
elaborate on this but it is probably important to do so.) Of these 240 acres, 182 acres have been
identified as having slope-stability concerns or potential risk to property or the water system
infrastructure. Resource considerations include Ashland Creek, the water pipeline, water treatment
plant, and the access road.
The Winburn Parcel: This area is 160 acres centrally located in the watershed with a diversity of
older forest types including some mature forest that has yet to reach old growth conditions. Most
of this parcel has high to very high relative density and needs thinning. In order to insure ensure
continued survival of the largest overstory trees, additional density management is required. The:
primary concern in this area is making sure that the overstory trees are retained and late
successional values are protected or promoted.
Other important issues to consider here include water quality, resident fish populations on West
Fork Ashland Creek and Weasel Creek, dwarf mistletoe, and slope stability concerns on at least 40
acres of the area,
The mature condition of this forest in most of the Winburn parcel allow for the potential for the
Forest Lands Commission to showcase it's management philosophy here. As this area will receive
the most intense public review, it should be highlighted as an enlightened approach to managing
lands in the watershed. Careful evaluation of management options will determine the best
4
treatment(s) for the Winburn parcel. It is important to note that not all of the Winburn Parcel is
necessarily mature forest of late successional. Considerable in-stand and between-stand variation
in late successional values exist. Some values were modified by the previous harvest. Threats to
late successional values (e.g. wildfire, disease, insects, etc.) also vary by unit or stand. It is more
appropriate to describe the Winburn Parcel as being integral to the late successional reserve,
rather than being entirely late successional itself
Activities Will Be Based On Eco- Type as Designated by Landscape Unit
Each of the two locations has several different plant communities. In the Lower Watershed area,
the Ponderosa pine series, dry Douglas fir series, and moist Douglas fir series can be found. In the
Winburn Parcel, the moist Douglas fir series and the white fir series occur. One way to describe
these eco-types is as "Landscape Units" (Main in pub.). For each of these landscape units a
"desired future condition" will be described to illuminate what the goal is for the type. We should
consider what we want immediately after treatment is accomplished and then what things will look
like in 10 years and then in 20 years. (confusing sentence)
Coarse Woody Material (Additional text by Frank Betlejewski -is this where it goes?)
The general goal is to utilize large down logs to stabilize surface soils, increase organic content in
soils over the long term and provide habitat for the many organisms that depend on logs in various
stages of decay , We have data on existing coarse woody material (large down logs) in the
watershed on Winburn parcel and on Forest Service land. We recognize that much of our lands
(e.g. the 80-100 year old stands) are currently at the low end of the range for natural variation of
course woody material. One recommendation is to leave amounts 5% to 30% of the amount of live
trees present in the stand (Harmon 200 I). Where the amount falls depends on other management
considerations such as plant community, fire danger, rural interface, or potential for insect outbreak
to name a few. The Forest Service is leaving 10-20 tons per acre nearby as part of the Ashland
Watershed Protection Project.
While actions such as mortality salvage can immediately change forest structure by removing the
snags (and subsequently change down log amounts), a more subtle change in the dead wood
component of the Applegate basin has also occurred. Just as fire exclusion has changed the live tree
composition of the forest, fire exclusion has also had an effect on dead tree composition.
Down logs that used to be consumed during fires now have a longer residence time on sites as they
decompose rather than being consumed. This has allowed higher amounts (more tons to the acre) of
fuel to accumulate than what would have occurred with a more frequent fire return interval. In the
same fashion, the absence of fire that would have burned live or dead trees and caused them to fall
(created down logs), or killed live trees (created snags), reduced recruitment of down logs and snags.
If fire had not been excluded, there would be fewer snags and down logs overall, but more recently
killed trees providing more decay class 1 and 2 down logs and snags compared to today. Analyses of
down log and snag data from the Roseburg BLM supports this premise (White personal
communication)
5
........-"'_.~,.,<--
While the exact number of snags and down logs appropriate to a particular plant series with normal
.fire return interval is unknown, recent data analyses in southwestern Oregon do show some patterns.
Snags and down logs are not distributed in the same fashion across the landscape. Snags are
distributed in a more uniform pattern. One approach for managing snags in the Applegate is to
concentrate snags near streams to provide habitat in areas with higher use by wildlife. Snags should
be well distributed along the entire length of the stream. The per acre ratio between riparian area
snags and the number of snags managed for in the uplands is unknown, but a 2 to 1 ratio (2 in the
riparian area and 1 in the upland) is suggested as a starting point.
Down logs distribution is more complex. More than 50% of the acres analyzed show no large down
logs at all. The highest amount of down logs should be left in riparian areas for the reasons
mentioned above for snags. A slightly lower amount could be left on northerly aspects away from
streams; perhaps 67% to 75% of that seen along the streams. Away from streams, the southerly
aspects would have very few down logs. Three out of four acres would have no down logs at all with
the remaining 25% of the southerly aspects having 50 to 75% that seen on the northerly aspects of the
matrix. For example, if a riparian acre had 3 down logs, a northerly aspect acre might have 2, and
one out of4 southerly aspect acres would have one down log
Wildlife (Re-written by Anthony Kerwin)
During project layout and tree marking, trees that haye indications of nest sites or large cavities
will be retained. "^~dditionallogs will be added to the forest floor to provide needed micro habitat&:
PortiONS ef thc City o',,'Ncrship should bc rctaincd untrcatcd c',cn at exccssive densitics to provide
co','Cr, structural divcrsity, or other ',,'ildlifc habitat 'lalucs. It is bctieved that sufficicnt areas oj
uNtreatcd'legctation will bc retaincd/or othcr rcasons (c.g. slopc stability issblcs, prc commcrcial-
sizc classes, ctc) te pr01,ide fer this wildlife habitat nccd on an ownership ey watershed basis.
During project layout and tree marking, trees that have indications of nest sites or large cavities will
be retained. Additional logs will be added to the forest floor to provide needed micro-habitats.
Thinning will be minimized to reduce impact on wildlife. Treatment time will be restricted to
certain times of the year to minimize impact on breeding wildlife species; specific dates will be
determined based on wildlife survey results.
Should small tree removal be inadequate to reduce stand level densities to desired levels, girdling,
as opposed to removal, of large trees will be considered as an option. The goal is to provide for
large snags andfuture coarse woody debris.
6
Cutting trees within riparian corridors (within 150' of streams) will be minimized. Any thinning
that needs to be done within this zone will entail either girdling or retention of downed trees on site
as coarse woody debris unless there is an associated hazard.
Overall treatments will follow these guidelines to maintain or increase wildlife habitat
· Efforts will be made to reduce structural uniformity, horizontally across the landscape.
· Areas untreated because of slope stability issues or other reasons will be utilized to reduce this
horizontal structural uniformity or increase structural diversity
Treatments will aim to retain 1/4 acre of untreated, dense stands for every five acres
· Hardwoods will be retained where possible, especially in the larger age classes
· Canopy gaps will be created or existing gaps will be utilized to increase diversity across the
landscape
· Where possible, a multi-layered canopy will be retained or encouraged, providingfuel
reduction and density reduction goals can be reached
Additional Design Features
· We want to manage for more open stand conditions and lower stand densities on stable,
southerly aspects so that a more diverse vegitational community can be promoted, including
pines, hardwoods, and grasses. a diversity of tree species (e,g. more open canopy; 10'Ner
relative density) on sites which are clHTently supporting healthy hardwoods and pine and are-efl
stable slope positions.
· Geologically sensitive zones with high management risk (high density) will be assessed on a
case by case basis and thinned conservatively to ensure slope stability. These areas are likely to
need a series of entries for density reduction treatments.
· Trees selectedfor removal selection will be determined by a combination of variables,
including species, tree vigor, stand basal area, and individual tree radial growth rates.
· Planning will include further discussion with wildlife and soils experts to determine the amount
(and sizes) of snags and down woody that is needed for long term soil health, moisture storage,
and wildlife.
Methods
· Trees should be marked prior to cutting.
· Yarding will be done by helicopter.
· Haul Routes need to be"determined; it is likely that most of the loads will travel down Granite
Street and run through town on East Main to Siskiyou.
7
.........--~_..,-._~'""',"-"-~..,-'-,...',',..~---'-.._-."'.
Monitoring
It is expected that over time there will be changes in understory vegetation and tree growth,
however, the effects of the density reduction prescribed fire, or other silvicultural treatment aM
prescribed fire treatments need to be monitored to evaluate their effectiveness. Ideally, an
agreement with the university would be desirable as the work could be incorporated into the
curriculum for students and not be a cost for the city. At a minimum, existing Organon plots would
be re-measured the first spring/summer after density management and prescribed fire treatments
were completed. This would include photo points taken on the cardinal (north, south, east and
west) directions for a permanent visual record. (Note: photos should be taken before density
management as well.) Immediate impacts will basically be limited to the trees that are cut and the
"footprint" on the ground where felled trees land. Longer-term effects will develop by opening up
the canopy to varying degrees and reducing root structure in the deeper soil profiles. Reduction may
be very short term if thinning is light; root structure in deeper soil profiles may be improved if
more dominant trees are improved in vigor by stand density reduction.
Monitoring will be designed specifically to:
I) track the changes in ecosystem elements that are likely to change as a result of the density
reduction
2) compare effects of treatments at different locations
3) ensure that the desired effects are produced
Soils: surface erosion where the tree canopy is significantly reduced (how much is significant?);
slides or accelerated erosion in draws or geologically sensitive areas. (This can be done by contract
with most of it probably accomplished by Real Corps.) (Can we measure the rate of
acceleration?. . How?)
Implementation Monitoring:
There will be stages of review for interested parties to assess the progress of the project relative to
the stated goals.
Additional Information Needed
Economics
Logging plan (Marty) This should be integrated with Economics
8
,,--,-.---,^~.......-,,-,_.,--..,_.,.,_.
Desired Future Conditions (Long Term) For Lower Watershed Area may take several entries
Ponderosa Pine Series (Landscape Unit D)
This type of landscape occurs on upper slope and ridgeline positions and often are currently
dominated by WhiteleafManzanita. The stands of this type on City ownership have already been
treated (Manzanita removed) and are on a trajectory toward this DFC except that there is a general
lack of grass layer.
Pine series
. .25 residual relative density
. 80-100 leave basal area
. >25% live crown ratio on leave pine and hardwood trees; >30% on Douglas-fir
. 25-35% residual canopy closure
· will leave a component of the largest hardwood trees per acre up to 30% of the total stand basal
area.
Note: A range is important because we do not want every spot in every stand to have 80-100 leave
basal area. Variability is important! These numbers listed should be targets, not absolutes.
The specific numbers listed could be debated somewhat, but are certainly in the ballpark.
Note: J would also like to include a range of acceptable numbers, not just averages.
Dry Douglas Fir Series (Landscape Unit G, H, and J)
This type is generally on the upper 2/3 of south and west aspects with a mix of pine, Douglas fir,
Madrone and black oak on fairly dry sites, mostly with stable slopes. This type also occurs on
north and west aspects and lower 1/3 of some south slopes. These are good areas to manage for
pine and hardwoods.
9
.....-,--....-.. _...
Douglas-fir Series - Dry end
. .30-.35 residual relative density
. 80-120 leave basal area
. >35% average LCR in leave Douglas-fir; > 30% in pine and hardwoods
. 30-45% average leave canopy closure %
. will leave a component of the largest hardwood trees per acre up to 30% of the stand basal
area.; favor mostly black oak and secondarily Madrone
Moist Douglas Fir Series (Part of Landscape Unit J):
This type of landscape occurs on very steep northerly aspects in the southern half of the area,
Douglas fir is dominant with some Madrone and ponderosa pine present (but at a competitive
disadvantage). Slope stability is usually an issue.
Douglas-fir Series - Wet End
. .35-.40 residual relative density
. 100-150 leave basal area
. >35% average LCR in leave trees
. 35-50% leave canopy closure %
. will leave a component of the largest hardwood trees per acre up to 30% of the stand basal
area.; favor black oak and Madrone
White Fir Series
· .35-.45 residual relative density
. 110-150 leave basal area
· >35% average leave live crown ration (except pine - >30%; unlikely to find many
hardwoods)
· 40-60% leave canopy closure
10
~..~...~..._'
. manage for a hardwood component; unlikely to retain due to annual snow load
These are the areas adjacent to streams and draws that hold significantly more soil moisture than
upland areas; these areas are typically very steep with unstable soils and are important for
managing water quality and quantity; these areas are also important for many species of wildlife.
Density Management Discussion
In general, the goal is to leave the largest healthiest trees and remove the weakest and smallest
trees. This will primarily include removal of trees in the 20-90 year age class and 6"-18" diameter
size range. However, trees of larger/older size/age classes will be cut may be considered for
removal during this thinning if they fall under any of the following criteria:
1. The stand is of trees are all large and the steadily increasing stand density is compromising vigor
and long-term sustainability of the stand is too dense to sustain further growth as evidenced by
very slow growth rates and weakening crowns.
2. Trees that are heavily infected with Douglas fir dwarf mistletoe. Retention of infected Douglas-
fir may be more appropriate on the Winburn parcel (particularly larger brooms in older, larger
Douglas-fir) for spotted owl nesting habitat, structural diversity and other late successional
values. Retention of dwarf mistletoe infected Douglas-jir for other values (wildlife habitat,
structural diversity) should be balanced with potential for encouraging stand development
trajectories that could ultimately result in a significant decline of Douglas-fir in terms of
species composition. Wherever possible, isolation technology should be used where larger
infected trees can be retained if few understory Douglas fir exist in the immediate vicinity and
if the larger trees are surrounded by an adequate number of Madrone, black oak, pine, or white
fir. Removal of dwarf mistletoe infected Douglas fir in younger (< 1 00 year) understory cohorts
should be a priority in most situations, although some retention can still occur (in low
topographical positions; using isolation technology, etc.) In these cases, very large trees will be
left if they are surrounded by an adequate number ofmadrone, black oak, pine or white fir to
ensure long term stand stability if Douglas fir is reduced. (Light inf-ections or lo',ver crown
infections will be pnmed out).
3. In some cases, clumps of twe three or more large trees are growing together and may be
stressing each other in close proximity and removal of one or several could be considered,
especially if those removed are considerable smaller than those retained (e.g. one 24 inch DBH
pine is removed while three 36 inch pines are retained. In general clumps will be considered as
single trees with thinning occurring around them provided additional stand density reduction is
completed around them.
4. Hazard Trees along roads or near structures may be considered for removal.
11
~..._-