 |
|
Strategic Planning
and Policy Section's
Coarse Woody Debris Library
For More Information, Click on the Desired Title
- Woody Debris in the Forest of British Columbia: A Review of the Literature and Current Research -- Land Management Report Number 78
- Federal Forest Lands in British Columbia: A brief to the Old-Growth Project Research
Working Group
- Old-growth Forests and Canada's Carbon Balance
- Quantities of Coarse Woody Debris in Old-Growth Forests.
- Final Supplemental Environmental Impact Statement: On management of habitat for late-
successional and old-growth forest related species within the range of the northern spotted owl,
Volume 1
- Prediction of Forest Health, in part, with the Distribution of Coarse Woody Debris Biomass
- The Decay Classes of Coarse Woody Debris and the Wildlife That Use Them
- Dying, Dead, and Down Trees
- Seeing the Forest Among the Trees: The Case for wholistic forest Use
- Dead and Down Woody Material
- Vegetation Inventory Working Group Pilot
- Appendix 24--Wildlife Uses of Downed Logs
- From the Forest to the Sea: A Story of Fallen Trees
- Guidelines for Maintaining Biodiversity During Juvenile Spacing
- Source distances for coarse woody debris entering small streams in western Oregon and
Washington
- Concepts in Ecosystem Management
- Characteristics of Logs Used by Western Red-Backed Voles, Clethrionomys californicus,
and Deer Mice, Peromyscus maniculatus
- Plant and Mammal Changes on a Clearcut in West-Central Oregon
- Coarse Woody Debris in Douglas-Fir Forests of Western Oregon and Washington
- Use of Woody Ground Litter as a Substrate for Travel by the White-Footed Mouse,
Peromyscus leucopus
- Scale Dependent Analyses of Habitat Selection by Marten in the Sub-boreal Spruce
Biogeoclimatic Zone, British Columbia
- Long-Term Experiments on Log Decomposition at the H.J. Andrews Experimental Forest
- Proceedings of the Forest Ecosystem Dynamics Workshop
- The Importance of Seral Stage and Coarse Woody Debris to the Abundance and
Distribution of Deer Mice on Vancouver Island, British Columbia
- Rotten Luck--The Role of Downed Wood in Ecosystems
- Wildlife Habitats of the North Coast of California: New Techniques for Extensive Forest
Inventory
- Economic Implications for Management of Structural Retention on Harvest Units at the
Blue River Ranger District
- Woody Debris and Abundance of Rodents on Clearcuts in Sub-Boreal Spruce Forest
- Effects of Some Clearcutting Practices on Small-Mammal Populations in Western Oregon
- Use of Woody Debris by Plethodontid Salamanders in Douglas-Fir Forests in Washington
- Coarse Woody Debris and Debris-Dependent Wildlife in Logged and Natural Riparian
Zone Forests--A western Oregon Example
- Coarse Woody Debris in Mixed-Conifer Forests - Sequoia National Park, California
- Southern Red-backed Vole, Clethrionomys gapperi, Populations in Relation to Stand
Succession and Old-growth Character in the Central Rocky Mountains
- Small Mammal Mycophagy near Woody Debris Accumulations in the Stehekin River
Valley, Washington
- Small Mammal Populations and Food Selection in Relation to Timber Harvest Practices in
the Western Cascade Mountains
- Small Mammals and Reforestation Following Prescribed Burning
- Small Mammals in old Field Succession
- Input and decay of coarse woody debris in coniferous stands in western Oregon and
Washington
- Ecology of Coarse Woody Debris in Temperate Ecosystems
DOCUMENT #1
Woody Debris in the Forest of British Columbia: A Review of the Literature and Current
Research -- Land Management Report Number 78
CITATION:
Caza, C. L. 1993. Woody Debris in the Forests of BC: A Review of the Literature and Current
Research. BC Ministry of Forests, Land Management Report, Number 78, Research Branch,
Victoria, February 1993.
KEYWORDS\CONCEPTS: Utilization, geomorphology, micro-climate, micro-topography, organic
matter, ecosystems, microorganisms, habitat, diversity, old-growth forests, hill slope, invertebrates, bark
beetles, wood borers, termites, carpenter ants, decomposition, reforestation, seedlings, soils, silviculture.
SYNOPSIS:
The authors had several objectives in mind in the undertaking of this report: to review the published
literature on the ecology of woody debris; to determine what data are available on amounts of wood debris
in BC forests, to identify proposed or ongoing research on woody debris within the Ministry of Forests, and
to discuss the research needed to fill the gaps in qualitative and quantitative understanding of the role of
woody debris in BC Forests. An annotated bibliography with abstracts was also prepared as part of the
final report and is included as Appendix 3.
Top of Document
DOCUMENT #2
Federal Forest Lands in British Columbia: A brief to the Old-Growth Project Research Working Group
CITATION:
Trofymow, J. A., June 8, 1990. Forestry Canada. Federal Forest Lands in British Columbia: A
brief to the Old-Growth Project Research Working Group. pp. 10
KEYWORDS\CONCEPTS: National forests, forest inventory, unharvested forest, national parks,
conservation areas, Indian lands, military lands, transport lands, environmentally sensitive areas.
SYNOPSIS:
The purpose of this brief is to describe the forest inventory data available for federal lands, the amount of
forest land and the potential for significant areas of old-growth forests on those lands. Federal lands
comprise about 1% of the total land area in BC. Approximately 60% of that 1 million her. contain
productive forests. With the exception of the National Parks, few of the federal forest lands potentially
contain significant (>100 ha) reserves of old-growth forests. Most of the lands are in small holdings,
although the Chilcotin Military Reserve and Dominion Coal Blocks potentially contain several thousand
hectares of mature or older unharvested forest. Some military lands on the coast contain small areas of
rarer forest types in the CDF biogeoclimatic zone.
Top of Document
DOCUMENT #3
Old-growth Forests and Canada's Carbon Balance
CITATION:
Trofymow, J.A. June 8, 1990. Forestry, Canada. Old-growth forests and Canada's carbon balance,
A brief to the Old-Growth Project Research Working Group. pp. 7
KEYWORDS\CONCEPTS: Deforestation, fossil fuel, reforestation, old-growth forests, carbon dioxide,
ecosystems, climatic change, biogeoclimatic zones, greenhouse gases, forest biomass, forest soils.
SYNOPSIS:
Over the last century, land use changes such as deforestation increasing fossil fuel consumption have been recognized as major causes of the rise in atmospheric C. Reforestation has been proposed as a means to offset further increases in atmospheric C. As a result, questions have been raised as to relative importance of old-growth and young forests as sinks for CO2. Conversion of old-growth forests in the US has resulted in a net release of significant amounts of C to the atmosphere. Little information is available on the amount and nature of the C contained in BC forest ecosystems.
Climatic changed induced shifts in the distribution of biogeoclimatic zones may be of importance in the
choice of location and extent of old-growth conservation areas. While significant shifts in the ecoclimatic
regions of Canada have been predicted as a result of global warming, no predictions are available for BC.
The complex effects of BC's topography requires that a more comprehensive approach be used. Little is
known if the direct effects of increased CO2 concentrations on tree growth will be able to compensate for
the indirect effects of increased CO2 on climate.
Top of Document
DOCUMENT #4
Quantities of Coarse Woody Debris in Old-Growth Forests.
CITATION:
Trofymow, J. A., Forestry Canada. Beese, W. J., MacMillan Bloedel, September 1990. Forestry Canada.
Quantities of coarse woody debris in old-growth forests. A brief to the Old-Growth Project
Research Working Group. pp. 21.
KEYWORDS\CONCEPTS: temperate forests, terrestrial systems, coastal forest, Pseudotsuga Menzeisii,
Pseudotsuga - Tsuga heterphylla, Picea sitchensis, geomorphic agents, habitat aquatic, terrestrial,
ecosystems, biological, decomposition.
SYNOPSIS:
The purpose of this brief is to describe what information is available on the amounts of CWD in old-
growth forests, particularly for those forest types found in BC. Such information is needed to develop
suitable definitions of old-growth forests and to develop guidelines for CWD in managed forests.
Hopwood (1991) has summarized some of the guidelines on CWD management for forests in the US
Pacific Northwest.
Top of Document
DOCUMENT #5
Final Supplemental Environmental Impact Statement: On management of habitat for late-
successional and old-growth forest related species within the range of the northern spotted owl,
Volume 1
CITATION:
F.E.M.A.T. February 1994. Final Supplemental Environmental Impact Statement: On management
of habitat for late-successional and old-growth forest related species within the range of the
northern spotted owl, Vol. 1. pp. S-19-S-20.
KEYWORDS\CONCEPTS: Coniferous forests, habitat, mammals, riparian zones, diversity, fish,
aquatic, watersheds, successional reserves, northern spotted owl, cavity nester, Congressionally Reserved
Areas, connectivity.
SYNOPSIS:
Temperate coniferous forests of the Pacific Northwest provide habitat for a diverse array of mammal
species. habitat components important to mammals other than bats include: dead, standing wood; dead,
downed wood; live old-growth trees, and riparian zones. Large, decayed logs and snags are important to
many mammals as resting and denning sites. Large expanses of live, old-growth trees are important to
some mammas such as the fisher because they provide continuous canopy cover.
Top of Document
DOCUMENT #6
Prediction of Forest Health, in part, with the Distribution of Coarse Woody Debris Biomass
CITATION:
St. Pierre, Betsy. 1993. Distribution of Coarse Woody Debris Biomass. Wildlife Habitat Canada
Research Proposal, Department of Biology and Institute for Research on Environment and Economy,
University of Ottawa. pp. 15.
KEYWORDS\CONCEPTS: Biodiversity, biomass, wildlife, temperate forests, species composition,
snags, ecosystem, soil stability, nutrient cycling, moisture retention, habitat, mycorrhizal fungi, decay,
bacteria, fungi, decomposition.
SYNOPSIS:
Accelerating losses of both biodiversity and long-term productivity may now be more threatening to the
integrity of the few remnant temperate rather than tropical ecosystems. Temperate forests with enough
coarse woody debris biomass to produce a variety of size and decay classes may contain the structural
hetrogeneity necessary for many kinds of geomorphic and habitat functions. An index of structural
diversity produced by a gradient of biomass may provide a state variable for predicting effects of further
disturbance on functional and biotic diversity in these forests.
The objectives of this research are to (1) compare the distribution of CWD biomass in five decay and size
classes in natural vs. harvested forests with similar conditions affecting CWD input and decay rates and (2)
predict the distribution of CWD biomass over decay and size classes which (a) maximize species diversity
of five ecologically important groups and (b) stabilize at least one ecosystem function such as water
holding capacity or soil organic matter (SOM) inputs.
Most CWD biomass is expected to be found in unlogged vs. logged forests and in large undecayed vs.
small logs. The expected additional biomass and structural heterogeneity in natural forests is expected to
be associated with increased diversity in five indicator groups, inputs of potential SOM, and water storage
capacity in the forest floor. Permanent plots will be established for measuring cumulative effects of
continuous CWD inputs and decay. The results will be important for : (1) scientists who are developing
ecological theory regarding the role of heterogeneity in ecosystem function; (2) landscape architects who
restore damaged souls and simplified ecosystems; and (3) forest managers who wish to sustain biotic and
functional diversity while extracting fiber.
Top of Document
DOCUMENT #7
The Decay Classes of Coarse Woody Debris and the Wildlife That Use Them
CITATION:
Tripp, Tania. August 1994. The Decay Classes of Coarse Woody Debris and the Wildlife that can
use them. Integrated Resource Section, Ministry of Forests, Victoria, British Columbia. pp. 16
KEYWORDS\CONCEPTS: old-growth forest, migration, classification, minerals, nitrogen, cellulose,
mammals, fungi, bacteria, sapwood, bark beetle, salamander, predators, invertebrates, vertebrates, burrow
systems.
INTRODUCTION:
Coarse Woody Debris (CWD) is used for a wide variety of purposes, from feeding and breeding to
preening, by numerous wildlife species. Factors influencing the type and extent of animal use include
physical orientation (vertical or horizontal), size (diameter and length), decay state, species of CWD and
overall abundance of CWD.
There are three major sources of CWD in an old-growth forest: (1) uprooting of live trees, with or without
complete crowns; (2) breakage of crown and stem of live trees; an (3) breakup and fall of snags. Because
size of trees and the manner in which woody material comes to be on the ground vary widely, the resulting
pieces of woody debris are heterogeneous in size and shape. Regardless of its original size, wood passes
through the various stages of decay; the smaller it is, the faster it breaks down and disappears.
Top of Document
DOCUMENT #8
Dying, Dead, and Down Trees
CITATION:
Hunter, Malcolm L. Date ?. Regents Prentice Hall. Wildlife, Forests, and Forestry; Principles of
Managing Forests for Biological Diversity. Dying, Dead, and Down Trees. pp. 157-180,
Chapter 10.
KEYWORDS\CONCEPTS: Deadwood, ecosystem, organic matter, nutrients, fauna, organisms,
decomposed, decay, heartwood, termites, salamanders, flora, tree species, vegetation, snag, fungi, bark
beetles, deciduous species, wildlife, cavity-using, nest boxes, clearcuts.
SYNOPSIS:
To many people there is nothing quite so useless as a dead tree, except possibly a fifth wheel on a cart, and
when people are called "deadwood" it is not because they are mature and respected members of an
organization. It is hardly surprising that people find dead things unattractive. It is even less surprising that
most foresters would perceive a dead tree as an affront to their efforts because, if they have done their job
well, trees are harvested before they die and go to waste. No one denies truisms such as "death is part of
life"; it is simply a choice between a quick, meaningful death effected by a machine versus a slow, rotting
death brought on by disease and other debilitating agents. Unfortunately, there is a basic flaw in this
perspective: Dying, dead, and down trees are important components of forest ecosystems and cannot be
excised without incurring many negative consequences.
Top of Document
DOCUMENT #9
Seeing the Forest Among the Trees: The Case for wholistic forest Use
CITATION:
Hammond, Herb, Date ?. Seeing the Forest Among the Trees: The Case for Wholistic forest
Use. pp. 29-30.
KEYWORDS\CONCEPTS: Snags, micro-climates, old-growth, mammals, organic matter, mycorrhizal
fungi, habitat cavity, forage, insects, defoliating, bacteria, fungi, decomposers.
SYNOPSIS:
One of the most important aspects and legacies of ancient forests are large old trees which became large
dead trees. Large snags (standing dead trees), fallen trees on the land, and fallen trees in streams or other
water bodies are unique "products" of old growth forests.
This report looks at the structural framework of forests. As these giants fulfill their life cycle in the old
growth forest--first as standing live trees, then as snags, next as fallen trees, and finally as decomposing
organic matter, giving birth to forest soil--forests of the past are linked to today's forests and forests of the
future.
Top of Document
DOCUMENT #10
Dead and Down Woody Material
CITATION:
Bartels, R., Dell, J.D.; Knight, R.L.; Schaefer, G. 1985. Management of Wildlife and Fish Habitats in
Forests of Western Oregon and Washington, Part 1--Chapter Narratives, Dead and Down
Woody Material. United States Department of Agriculture, Forest Service, Pacific Northwest Region.
Chapter 8, pp. 171-186.
KEYWORDS\CONCEPTS: Tree mortality, forest management, snags, structural features, old-growth,
decomposed, alder, cottonwood, moisture content, nitrogen, nonsymbiotic bacteria, regeneration, nutrient
cycling, mycorrhizal fungi, lichens, spores, fungi.
SYNOPSIS:
Dead and down woody material in the form of stumps, root wads, bark, limbs, and logs, in various stages
of decay, occurs in most forest ecosystems. This is especially true of the temperate and high temperate
conifer forests west of the Cascade Range where highly productive forest sites are capable of procuring
large volumes of wood fiber. These dead and down materials have long been viewed as potential wood
products that should be salvaged, as fuels that create fire hazards, as physical barriers to tree planting, and
as a haven for small mammals which may impede forest regeneration. All of these are valid concerns;
however, dead and down woody material serves many important functions that should be recognized. Not
only is this material important in mineral cycling, nutrient mobilization, and natural forest regeneration, but
it also creates a structure and diversity of habitats that are valuable to a great many wildlife species,
terrestrial and aquatic.
Intensified forest management, responding to the ever-increasing demand for forest products, will have a
strong influence on the amount and distribution of woody material that remains as wildlife habitat through
present and future stand rotations. Leaving the perpetuation of large down material to chance will
probably result in its disappearance from the managed forests of the future, along with the loss of
dependent plant and wildlife species.
Top of Document
DOCUMENT #11
Vegetation Inventory Working Group Pilot
CITATION:
Parminter, J. 1994. Vegetation Inventory Working Group Pilot. Ministry of Forests, Research Branch.
pp. 17
KEYWORDS\CONCEPTS: graminoids, bryophyte, lichen, shrubs, nutrients, topography, ecological,
xeric, subxeric, submesic, mesic, subhygric, hygric, hydric, subhydric, land cover designation, humus, soil
organic horizon.
SYNOPSIS:
This report lists the attributes, with the accompanying instructions describing how the data was collected
and two reference sheets contain summaries of the newer material for field use. Ecological attributes are
also included in order to integrate information on site conditions, site history, soil, understorey vegetation,
wildlife trees and coarse woody debris with the timber inventory data.
No tree descriptions are included here ass they form part of the timber data rather than the ecological data
collected at each main plot. The information collected on the timber data forms enables stand descriptions
based on numbers of trees by species, size, (DBH and height), age and condition (quality and wildlife tree
class).
Top of Document
DOCUMENT #12
Appendix 24--Wildlife Uses of Downed Logs
CITATION:
Thomas, J.W. (ed.). 1979. Appendix 24--Wildlife uses of downed logs, In: Wildlife habitats in
managed forests, the Blue Mountains of Oregon and Washington. USDA For. Ser. Agric. Handb.
553. Washington, D.C. pp. 392-398.
KEYWORDS\CONCEPTS: amphibians, reptiles, birds, log classes, cover, feeding, reproduction.
SYNOPSIS:
In chart form the various wildlife within the forest which uses downed logs. Includes cover, feeding, and
reproduction.
Top of Document
DOCUMENT #13
From the Forest to the Sea: A Story of Fallen Trees
CITATION:
Maser, C., Tarrant, R.F., Trappe, J.M. and Franklin, J.F. (tech. eds). 1988. From the Forest to the
Sea: A Story of Fallen Trees. PNW Research Station, USDA Forest Service, Portland, Oregon.
pp. 3.
KEYWORDS\CONCEPTS: Decomposition, habitat diversity, ecosystem function, land, water, sea.
SYNOPSIS:
Large, fallen trees in various stages of decay contribute much-needed diversity of ecological processes to
terrestrial, aquatic, estuarine, coastal beach, and open ocean habitats in the Pacific Northwest. Intensive
utilization and management can deprive these habitats of large, fallen trees. This publication presents
sound information for managers making resource management decisions on the impact of this loss on
habitat diversity and on ecological processes that have an impact on long-term ecosystem productivity.
Top of Document
DOCUMENT #14
Guidelines for Maintaining Biodiversity During Juvenile Spacing
CITATION:
FRDA. Date? Guidelines for Maintaining Biodiversity during Juvenile Spacing. Canada-British
Columbia, Forest Resource Development Agreement. pp. 1
KEYWORDS\CONCEPTS: Stand level attributes, snags, wildlife, decaying, soil nutrients, understorey,
fungi.
SYNOPSIS:
A one page document describing habitat features at the Stand Level, such as snags, live trees, coarse woody
debris and understory shrubs and herbs.
Top of Document
DOCUMENT #15
Source distances for coarse woody debris entering small streams in western Oregon and
Washington
CITATION:
McDade, M.H., Swanson, F.J., McKee, W.A., Franklin, J.F. and Van Sickle, J. September, 1989. Source
distances for coarse woody debris entering small streams in western Oregon and Washington. Can.
J. For. Res. 20: 326-330.
KEYWORDS\CONCEPTS: Forest ecosystems, stream-bank erosion, landslides, riparian forests, forest-
stream linkages, old-growth forests, hardwoods.
INTRODUCTION:
The objective of this study was to determine the source-distance patterns of coarse woody debris in
selected streams flowing through natural conifer forests in the Cascade and Coast mountains of western
Oregon and Washington. Several stand and landform conditions were sampled to estimate their effects on
source-distance patterns of stream-side forests. The authors sampled old-growth and mature forests
containing confers and hardwoods to provide data on a range of tree heights. Hillslope steepness was
considered in the sampling as the authors expected that if debris slid down steep slopes, source distances
would be greater at sites with steeper side slopes and narrower floodplains. Sampled sites included a range
of stream orders from first to third because floodplain width in this region generally increases with
increasing stream order.
Top of Document
DOCUMENT #16
Concepts in Ecosystem Management
CITATION:
Olympic Learning Centre. 1994. Concepts in Ecosystem Management: Coarse Woody Debris;
Forest Structure; Forest Canopy; Forest Edges; Underground Ecosystems, Stream Processes;
Landscape Patterns
KEYWORDS\CONCEPTS: Nutrients, closed forest, mycorrhizzal fungi, photosynthesis, global organic
carbon, bromeliads, predators, insects, decomposition, northern spotted owl, harvesting, clear-cut, stream
processes, water chemistry, landscape, biological functions, drainage basin, ecological functions.
SYNOPSIS:
A series of information sheets, each two pages long on coarse woody debris, forest structure, forest canopy,
forest edges, underground ecosystems, stream processes, and landscape patterns.
Top of Document
DOCUMENT #17
Characteristics of Logs Used by Western Red-Backed Voles, Clethrionomys californicus,
and Deer Mice, Peromyscus maniculatus
CITATION:
Hayes, J.P. and Cross, S.P. 1987. Characteristics of Logs used by Western Red-backed Voles,
Clethrionomys californicus, and Deer Mice, Peromyscus maniculatus. Canadian Field Naturalist. 101
(4): 543-546.
KEYWORDS\CONCEPTS: Red-backed vole, Clethrionomys californicus, Deer Mouse, Peromyscus
maniuclatus, logs, microhabitat.
ABSTRACT:
Capture success at 48 structurally varied logs was compared for both the Western Red-backed Vole and the
Deer Mouse. The number of vole captures was positively correlated with mean log diameter and the size
of log overhang--that is, the semitrangular space between the edge of the log and the ground. Log
overhang may provide cover and serve as a travel corridor for Western Red-backed Voles. The number of
Deer Mouse captures was not significantly correlated with any of the measured log variables. The state of
the log did not significantly influence capture success of either species.
Top of Document
DOCUMENT #18
Plant and Mammal Changes on a Clearcut in West-Central Oregon
CITATION:
Gashwiler, Jay, S. 1970. Plant and Mammal changes on a clearcut in west-central Oregon. Ecology
51: pp. 1018-1026.
KEYWORDS\CONCEPTS: Clearcut, Deer mice, Peromyscus maniuclatus, watershed, precipitation,
old-growth forest, volcanic origin, vegetation, ground cover, understorey, herbaceous cover, fireweed,
woody plants, stump collars, seedlings,.
ABSTRACT:
Plant composition and coverage and small mammal populations were compared in virgin forest (control)
and clearcut (experimental) areas from April 1954 to October 1965. Changes in ground cover vegetation
were modest on the control area but marked on the experimental area. A late fall burn on the experimental
area may have retarded herbaceous plant establishment. Nearly half of the herbaceous species were
invaders not found in the virgin Douglas-fir (Pseudotsuga menziessi) forest. Ground plant coverage was
less than 23% in the virgin forest; one year after the clearcut area was burned, the cover was 2%; and by
ten years it was above 53%. Woody plant coverage (mostly sprouts) was slightly more abundant the first 2
years after burning. Herbaceous species then became dominant for a 3-year period, after which woody
plants gradually gained dominance.
Deer mice (Peromyscus maniculatus) increased on the experimental area soon after the burn. The
populations varied from an estimated 0.9 to 12.8 animals per acre and fluctuated widely and irregularly.
Townsend's chipmunk (Eutamias townsendii), Oregon vole (MIcrotus oregoni), and snowshoe hare (Lepus
americanus) populations also increased on the area at different periods after the burn. Trowbridge's shrews
(Sorex trowbridgii), vagrant shrews, (sorex vagrans), and ermine (mustela erminea) were present on both
areas in relatively low numbers. Redback voles (Clethrionomys occidentalis), Douglas' squirrels
(Tamiasciurus douglasii), and northern flying squirrels (Glaucomys sabrinus), were not found on the
clear-cut. California ground squirrels (Spermophilus beecheyi), migrated to the clearcut and established a
modest population. Richardson's voles (Microtus richardsoni), jumping mice (Zapus trinotatus), bushy-
tailed woodrats (Neotoma cinerea), and a pika (chotona princeps) were visitors.
Top of Document
DOCUMENT #19
Coarse Woody Debris in Douglas-Fir Forests of Western Oregon and Washington
CITATION:
Spies, Thomas et al. 1988. Coarse Woody Debris in Douglas-Fir Forests of Western Oregon and
Washington. Ecology. 69(6): 1689-1702.
KEYWORDS\CONCEPTS: decay rate, fire, old-growth stands, Pacific Northwest, succession,
Pseudotsuga menziesii.
ABSTRACT:
Amounts and structural characteristics of coarse wood debris (CWD) were examined in relation to stand
age and site moisture condition in 196 Pseudotsuga menziesii stands in western Oregon and Washington.
Stands ranged from 40-900 year old, and most, if not all, originated after fire. In a chronosequence from
the Cascade Range, the amount of CWD followed a U-shaped pattern for stands <500 yr. old, with
moderate levels (92 Mg/ha) in stands <80 yr. old, lowest levels (<50 Mg/ha) in stands 80-120 yr. old, and
highest levels (173 Mg/ha) in stands 400-500 yr. old. After 500 yr. the amounts of CWD declined to
intermediate levels. In the southern Coast Range, lowest levels (32 Mg/ha) of CWD were in the youngest
stands (60-80 yr.) primarily because they inherited little CWD from the preceding (prefire) stands. In the
Cascade Range, levels of CWD inherited from overall decay rate constant (k for snags and logs in the
Cascade Ranged, calculated indirectly from the chronosequence, was 0.029 yr. Volume and biomass of
CWD differed significantly in old growth stands (>200 yr. old) among site moisture classes. Dry sites
averaged 72 Mg/ha, moderate sites 137 Mg/ha, and moist sites 174 Mg/ha.
The dynamics of CWD were modeled for three fire histories, each beginning with an initial fire in an old-
growth stand but differing in number and severity of subsequent fires. All three models exhibited low
values of CWD between 80 and 200 yr. The lowest and most prolonged minimum in CWD during
succession occurred when additional fires burned early in succession, which probably happened preceding
many stands in the southern Coast Range. The results of the study indicate that a steady-state condition in
CWD may not be reached for >1000 yr., and that the nature and timing of disturbance play a key role in the
dynamics of CWD in the region.
Top of Document
DOCUMENT #20
Use of Woody Ground Litter as a Substrate for Travel by the White-Footed Mouse,
Peromyscus leucopus
CITATION:
Planz, J.V. and Kirkland, G.L. Jr.. 1992. Use of Woody Ground litter as a substrate for travel by the
white-footed mouse. Canadian Field-Naturalist. 106(1): 118-121.
KEYWORDS\CONCEPTS: White-footed mouse, Peromyscus leucopus, fluorescent tracking, deciduous
forest, habitat use, woody ground litter, predation risk.
ABSTRACT:
Use of woody ground litter by white-footed mice as a substrate for travel was studied in a middle-aged,
deciduous forest in south-central Pennsylvania using a fluorescent pigment tracking technique. Mark-
recapture data on 45 P. leucopus and mapped trails of 17 individuals were obtained from April through
December 1986. Following collection of data on the movements and habitat utilization of white-footed
mice in an unmanipulated system, selected quadrants within the study site were cleared of all woody
ground litter greater than 10 mm in diameter to assess the importance of such litter on habitat utilization
and movements by P. leucopus. There was a significant decrease in the number of captures of white-
footed mice on cleared plots between the pre- and post-litter removal phases of the study. Although woody
ground litter comprised only an estimated 8.2% of the ground cover on the study site, approximately half
the total distance traveled by P. leucopus was on woody ground litter. The use of woody ground cover
for travel by P. leucopus may represent a trade-off between the risks of predation from rattlesnakes
(Crotalus horridus) that use ground litter as ambush sites and nocturnal raptors that are more common and
employ auditory cues to locate prey.
Top of Document
DOCUMENT #21
Scale Dependent Analyses of Habitat Selection by Marten in the Sub-boreal Spruce
Biogeoclimatic Zone, British Columbia
CITATION:
Lofroth, E.C. and Steventon, J. D. 1993. Scale Dependent Analyses of Habitat Selection by
Marten in the Sub-Boreal Spruce Biogeoclimatic Zone. B.C. Ministry of Environment, Wildlife
Habitat Branch, Victoria, B.C. pp. 109.
KEYWORDS\CONCEPTS: Sub-boreal Spruce Biogeoclimatic zone, xeric habitat, wetlands, canopy
closure, marten, stand scale, ecosystems, habitat selectivity, voles, subnivean, foraging, regeneration.
ABSTRACT:
Winter habitat selection by radio-collared marten (Martes american) in the Sub-Boreal Spruce (SBS)
Biogeoclimatic Zone was examined at landscape, stand and patch scales between January 1988 and
September 1991. Capture data indicate that the moist cold subzone of the SBS was more productive as
marten winter habitat than the lower elevation dry cool subzone. Landscape scale habitat use for 7 adult
marten (4 males, 3 females) revealed that marten preferentially included mature to old-growth seral stage
habitat types of mesic to gyric moisture regimes within their home ranges. Three male marten included
substantial areas of young forest seral stage habitat types which may provide them with access to alternate
prey during periods of high prey population cycles. Stand scale analyses indicate that, within individual
home ranges, marten do not prefer any particular habitat types but do avoid some habitat types, particularly
young seral stages, xeric habitat types and wetlands. This apparent lack of preference at the stand scale is
likely a consequence of landscape level selectivity. Marten exhibited selectivity at the stand scale for
habitats types classified by their structural features. These habitat preferences were related to the
abundance of coarse woody debris, deciduous canopy closure, high shrub and low shrub closure, and
abundance and size of trees and snags. At the stand scale, marten did not prefer any particular class of
coniferous canopy closure. Within habitat types, marten were selective at the patch scale. Structural
characteristics at marten sites were significantly different from the prevailing characteristics of the habitat
types that these sites were in. Selectivity occurred for all structural attributes examined with the exception
of mean snag diameter. The author's results have implications for forest management, in particular forest
harvesting types, rates and cutblock sizes, site preparation tactics, and stand tending practices. If marten
are to be maintained in an area, forest management practices must be implemented that promote a
distribution of seral stages (including old growth) with structural features necessary for marten winter
habitat.
Top of Document
DOCUMENT #22
Long-Term Experiments on Log Decomposition at the H.J. Andrews Experimental Forest
CITATION:
Harmon, M.E. 1986. Long-Term Experiments on Log decomposition at the HJ Andrews
Experimental Forest. United States Department of Agriculture, Forest Service, Pacific Northwest
Research Station. pp. 1.
KEYWORDS\CONCEPTS: Decay, decomposition, Douglas-fir, fallen trees, Pacific silver fir, western
hemlock, western red cedar.
SYNOPSIS:
A long-term decomposition experiment was established at the HJ Andrews Experimental Forest, Oregon,
during 1985 to test the importance of substrate heterogeneity, colonization patterns, and invertebrates on
the decomposition of logs. The duration of the study is anticipated to be 200 years. A total of 530 logs (50
centimeters in diameter and 5.5 meters long) were placed at six old-growth forest sites. Characteristics
measured for each log at the start of the experiment included diameter, length, volume, surface area, bark
cover, and the total volume, density, and moisture content of outer bark, inner bark, sapwood, and
heartwood. A subsample of logs was examined for lignin, cellulose, ash, calcium, copper, iron, nitrogen,
potassium, magnesium, manganese, phosphorus, sulfur, and zinc content. Data on initial conditions and
subsequent measurements are being stored at the Forest Science Data Bank, Oregon State University,
Covallis.
Top of Document
DOCUMENT #23
Proceedings of the Forest Ecosystem Dynamics Workshop
CITATION:
Marshall, Valin. 1993. Proceedings of the Forest Ecosystem Dynamics Workshop. Government of
Canada, Province of Canada, pp. 98.
KEYWORDS\CONCEPTS: Forest ecosystem, socio-economic fabric, genetic resources, biodiversity,
global significance, chronsequences, western hemlock, old-growth, vegetation diversity, conservation.
INTRODUCTION:
As the 1990's began, Forestry Canada, Pacific and Yukon Region, embarked on a series of changes that
would better position the authors to address the new issues facing the forest sector. In this process a wide
range of clients were survey to identify the specific items of concern, and from their responses a new look
to programs was fashioned. Among the scientists affected were those associated with the Shawnigan Lake
Experiment studying fertilization and thinning. The group comprise specialists in fundamental aspects of
tree growth and forest ecosystems, and had evolved a team approach to their work. The new task was to
develop a research program that would take one of the most nebulous and intangible topics on forestry's
corporate table today--the environment.
This document summarizes the work completed up to the time of the full-scale review, and presents the
recommendations of the review panel. While the panel recommended a number of changes, it also
provided solid assurance that the Program is proceeding in the right direction, on several fronts that are
clearly of importance today.
Top of Document
DOCUMENT #24
The Importance of Seral Stage and Coarse Woody Debris to the Abundance and
Distribution of Deer Mice on Vancouver Island, British Columbia
CITATION:
Carter, David W. 1993. The importance of seral stage and CWD to the abundance and distribution
of deer mice on Vancouver Island, BC.
KEYWORDS\CONCEPTS: Forest landscapes, deer mouse, reproduction, herb, shrub, young forest,
mature forest, seral stages, microhabitat.
INTRODUCTION:
Abundance and demography of deer mice in herb, shrub, young forest, and mature forest seral stages of
coastal forest were examined during 1988 and 1989. Deer mice were more abundant in herb and shrub
seral stages than in young and mature forests. Deer mouse populations in younger seral stages produced
more juveniles and had greater rates of juvenile recruitment, whereas the population in the mature forest
had less immigration and higher adult survival. Deer mouse abundance was positively correlated with
abundance of coarse woody debris in all four seral stages. Woody debris had greater influence on deer
mouse abundance in the herb seral stage and mature forest than it did in the shrub seral stage and young
forest.
Fluorescent powder tracking was used to follow movements of deer mice and determine their habitat
selection in the herb seral stage and mature forest. Travel routes of deer mice in both habitats were
strongly associated with coarse woody debris. In the herb seral stage, deer mice usually traveled beside or
under pieces of woody debris, whereas in mature forest, deer mice usually traveled on top of the woody
debris. In coastal forest landscapes, coarse woody debris is an important habitat component which affects
the abundance, distribution and behavior of deer mice.
Top of Document
DOCUMENT #25
Rotten Luck--The Role of Downed Wood in Ecosystems
CITATION:
Environment Canada. Date ? Rotten Luck--The Role of Downed Wood in Ecosystems. (Brochure).
Environment Canada, Ministry of Forests, Province of British Columbia and The Centre for
Applied Conservation Biology, University of British Columbia.
KEYWORDS\CONCEPTS: Ecosystems, beetles, termites, bacteria, fungi, nutrients, shelter, predators,
growing sites, estuaries.
INTRODUCTION:
When a tree dies its life is only partly over. As wood decays it continues to play an essential role in may
different ecosystems--in forest, in streams, in estuaries and in the ocean. As they decay, fallen trees,
broken branches, slabs of bark and upturned roots:
* provide food
* provide shelter
* create growing sites for plants and fungi
* enrich and stabilize soils
* contribute to stream ecosystems
Downed wood is also a biological legacy--a link between present and future forests.
Top of Document
DOCUMENT #26
Wildlife Habitats of the North Coast of California: New Techniques for Extensive Forest
Inventory
CITATION:
Ohmann, Janet L. 1992. Wildlife Habitats of the north coast of California: new techniques for
extensive forest inventory. Forestry Sciences Laboratory. Portland, Oregon. pp. 48
KEYWORDS\CONCEPTS: Wildlife habitat relationships, multi resource inventory, forest inventory,
wildlife habitat assessment, snags, California (north coast).
BACKGROUND:
A study was undertaken to develop methods for extensive inventory and analysis of wildlife habitats. The
objective was to provide information about amounts and conditions of wildlife habitats from extensive,
sample-based inventories so that wildlife can be better considered in forest planning and policy decisions at
the regional scale. The new analytical approach involves identifying habitats present on field plots,
estimating area present in each habitat condition, and linking the habitat classifications with wildlife-
habitat relationship models to describe habitat suitability for wildlife species. The habitat classification
system and wildlife-habitat relationship models of the California Wildlife Habitat Relationship Program are
used in a a case study of the north coast region of California. Tree vegetation types occupy 93 percent of
all forest land, and shrub habitats occupy 5 percent. Redwood and Douglas-fir are the most abundant tree
habitats; chamise-redshank chaparral is the predominant shrub habitat. Outside parks and National Forests,
mid successional stages dominate the forest landscape in occupying two-thirds of the timberland area.
Two-thirds of forest stands have moderate or dense canopy closure. The suitability of available habitats for
reproduction and feeding for eight wildlife species are presented. The estimates of habitat area indicate the
availability and patterns of occurrence of these vegetation conditions at a broad scale and should be useful
in evaluating potential impacts of proposed actions affecting broad-scale alterations of habitat. The
estimates of habitat suitability are used appropriately in regional-level predictions of species occurrence
and habitat suitability. Extensive inventory data on special habitat elements such as snags, nontree
vegetation, and spatial features of habitat also can be used in resource assessments and ecological research;
for example, only 9 percent of the habitat area rated as being of high or medium suitability for reproduction
for pileated woodpeckers supports snag habitat required by the species. large snags are most abundant in
dense, pole-sized and larger stands in the redwood type and in large-treed stands of all densities in the
Douglas-fir type. Data from continuing forest inventories also are useful for regional level monitoring of
wildlife habitats and in habitat simulations.
Top of Document
DOCUMENT #27
Economic Implications for Management of Structural Retention on Harvest Units at the
Blue River Ranger District
CITATION:
Weigand, J.F. and Burditt, A.L. 1992. Economic Implications for Management of Structural
Retention on Harvest Units at the Blue River Ranger District. Blue River Ranger District,
Willamette National Forest, Oregon. pp. 17.
KEYWORDS\CONCEPTS: Timber harvests, stand structure, retention, green trees, snags, down wood.
BACKGROUND:
Timber sales offered at the Blue River Ranger District since the 1988 introduction of management for stand
structural retention were studied to describe and quantify, where possible, economic implications of that
management. Values for the potential lumber from merchantable green trees ranged from $102 to $1114
per acre among the harvest units surveyed thus far. Protecting residual stand structure by not broadcast
burning created an average savings of $237 per unburned acre. When postsale snag creation was necessary
to meet stand prescription requirements, average topping cost per tree was $44.50 in 1989 but dropped to
$32.50 in 1990/ Declines in revenues from future firewood sales may result from retention of stand slash
and down wood. Administrative costs for the USDA Forest Service and logging costs for contractors have
not been detailed. Response by bidders to sales with more than 2.0 million board feet of timber has not
significantly changed since management for residual stand structure was introduced. Concerns that
management for structural retention might reduce timber supplies for the wood products industry and
timber revenues for the Forest Service have not been borne out thus far.
Top of Document
DOCUMENT #28
Woody Debris and Abundance of Rodents on Clearcuts in Sub-Boreal Spruce Forest
CITATION:
Nowotny, C., Sullivan, T.P. and Harestad, A.S. 1990. Woody debris and abundance of rodents
on clearcuts in sub-boreal spruce forests. Unpublished manuscript. 21 pgs.
KEYWORDS\CONCEPTS: Rodents, deer mice, micro-habitat, debris volume, predators, decomposition.
SYNOPSIS:
The authors examined the relationship between rodent densities and volumes of post-harvest debris in
clearcuts in sub-boreal spruce forest of central BC. Estimates of rodent densities were obtained using
conventional grid systems and an index line method. volumes of debris were calculated from diameter
measurements made along transect lines. Densities of individual species and of all rodents combined were
compared with debris volumes. Although a wide range of rodent densities and debris volumes were
recorded, no significant correlation's between the two variables were obtained.
Top of Document
DOCUMENT #29
Effects of Some Clearcutting Practices on Small-Mammal Populations in Western Oregon
CITATION:
Hooven, E.F. and Black, H.C. 1976. Effects of some clearcutting practices on small mammal
populations in western Oregon. Northwest Sci. 50: 189-208.
KEYWORDS\CONCEPTS: harvesting, vegetation, topography, precipitation, clearcutting, crown cover,
understorey, perennials, logging, vegetative composition.
ABSTRACT:
Changes in small mammal populations and vegetation on two clearcuttings and one uncut stand of 125 year
old Douglas-fir, in the foothills of the Cascade Mountains in western Oregon were noted, from 1964 to
1970. Mark-release-capture methods were followed each summer on a monthly basis. In all, more than
3630 small mammals of 23 species were caught during three years of live-trapping from 1968 to 1970.
Five species comprised more than 90 percent of the total catch.
Logging and controlled slash burning profoundly affected habitats occupied by small mammals. rapid
changes in plant abundance occurred in the unburned unit, and vegetative recovery was dominated by
herbaceous annuals two years after clearcutting.
Shrews and chipmunks were affected adversely by logging. conversely, populations of deer mice and
Oregon creeping voles were affected favorably by both logging and slash burning and increased in
abundance after treatment on both clearcuttings.
Top of Document
DOCUMENT #30
Use of Woody Debris by Plethodontid Salamanders in Douglas-Fir Forests in Washington
CITATION:
Aubry, Keith B., Lawrence, L.C. and Hall, P.A. 1988. Use of woody debris by plethodontid
salamanders in Douglas-fir forests in Washington. USDA For Serv. Pac. Northwest Res. Stn.,
Olympia, Washington. No 65 of the Old-growth For. Wildlife Habitat Project. pp. 32-32.
KEYWORDS\CONCEPTS: Harvesting, Douglas-Fir, amphibian, spotted owl, northern flying squirrel,
red tree vole, Pacific Northwest, natural regeneration, silvicultural treatments.
ABSTRACT:
Ensatina eschscholtzii was found most often under pieces of bark, whereas Plethodon vehiculum occurred
primarily under logs. Captures of both species were highest in young stands, but occurred in all age
classes. The results suggest that the retention of coarse woody debris in managed forests would provide for
the habitat needs of these species.
Top of Document
DOCUMENT #31
Coarse Woody Debris and Debris-Dependent Wildlife in Logged and Natural Riparian
Zone Forests--A western Oregon Example
CITATION:
Cline, Steven P., and Phillips, Charles A. 1983. CWD and debris-dependent wildlife in logged and
natural riparian zone forest-A western Oregon example. In Proceedings of the symposium on
Snag Habitat management. June 7-9 1983, Northern Arizona University, Flagstaff. USDA For. Ser. Gen.
Tech. Rep. RM-99. Rocky Mountain Forest and range Experiment station, Fort Collins, Colorado.
KEYWORDS\CONCEPTS: Riparian zone, biological interaction, stream ecosystems, timber
management, landslides, buffer strips.
SYNOPSIS:
A reconnaissance study was carried out to determine some structural aspects of riparian zone forests and
the effects of logging upon woody debris wildlife habitat. A literature search was also conducted to gather
information upon the debris--dependent wildlife in riparian zone forests, and how they are influenced by
timber management. this information was synthesized in a hypothetical example of snag management in
the Coast Range of Oregon. The authors found that snag habitat of the larger woodpeckers was reduced by
clearcutting we it was predicted that shortened rotations in the future will reduce or even locally
exterminate 20 birds and five mammal species. Snag requirements were calculated of hole-nesting birds
that are not met using only snags in riparian zone buffer strips. An active program of dead tree
management on upland areas is also necessary.
Top of Document
DOCUMENT #32
Coarse Woody Debris in Mixed-Conifer Forests - Sequoia National Park, California
CITATION:
Harmon, Mark E., Cromack, K. and Smith, B.G. 1987. CWD in mixed-conifer forests. Sequoia National
park, California. Can. J. For. Res. 17: 1265-1272.
KEYWORDS\CONCEPTS: Forest stands, decay classification, chronosequence, tree species, carbon,
nitrogen, riparian zone.
SYNOPSIS:
The decay rate of Abie concolor logs and cover, mass, and volume of logs and snags in six mid-elevational
forest stands of Sequoia National Park, are reported.
Top of Document
DOCUMENT #33
Southern Red-backed Vole, Clethrionomys gapperi, Populations in Relation to Stand
Succession and Old-growth Character in the Central Rocky Mountains
CITATION:
Nordyke, Kirk A., and Buskirk, Steven W. 1991. Southern red-backed vole, Clethrionomys gapperi,
populations in relation to stand succession and old- growth character in the central Rocky mountains.
Canadian Field-Naturalist. 105(3): 330.
KEYWORDS\CONCEPTS: southern red-backed vole, conifer, old-growth stands, succession.
ABSTRACT:
The effects of old-growth character, microhabitat characteristics, and successional stage on the Southern
Red-backed Vole were investigated in conifer forests of southeastern Wyoming in 1986 and 1987. Small
mammals were snap-trapped in Lodgepole Pine, mature spruce-fir and old-growth spruce-fir habitat types.
Vole abundance was greatest and body condition best in old-growth spruce-fir. vole captures best fit a
second degree polynomial model when regressed on old-growth rating in 1987; understory cover followed
a similar pattern with rating. Abundance was positively correlated with understory cover both years, and
because of this relationship and the bimodal response of both of these to old-growth rating, understory
cover may influence distribution of C. gapperi more than do other habitat features. Vole abundance was
positively correlated with stage of decay of logs.
Top of Document
DOCUMENT #34
Small Mammal Mycophagy near Woody Debris Accumulations in the Stehekin River
Valley, Washington
CITATION:
Rhoades, F. 1986. Small Mammal Mycophagy near woody Debris Accumulations in the Stehekin
River Valley, Washington. Northwest Science. 60(3): 150-153.
KEYWORDS\CONCEPTS: fungi, hypogeous fungi, sporocarps, spores.
ABSTRACT:
Fungi are important in the diet of many small mammals. The digestive tracts of 32 small mammals trapped
near woody debris piles were examined for presence and abundance of spores of hypogeous, epigeous and
wood-inhabiting fungi. All animals contained fungal spores, usually in abundance high enough to suggest
that each animal had recently consumed fungi. Spores of hypogeous fungi were the most abundant,
especially those of genera Alpova and Rhizopogon.
Top of Document
DOCUMENT #35
Small Mammal Populations and Food Selection in Relation to Timber Harvest Practices in
the Western Cascade Mountains
CITATION:
Gunther, P.M., Horn, B.S. and Bab, G.D.. 1983. Small Mammal Populations and Food Selection in
Relation to Timber Harvest Practices in the Western Cascade Mountains. United States Forest Service,
Skykomish Ranger District, Washington. Northwest Science. 57(1): 32-44.
KEYWORDS\CONCEPTS: logging, western hemlock, clearcuts, vegetation, food selection.
ABSTRACT:
In contiguous forests, cover is an important factor limiting small mammal presence and relative abundance.
Small mammals were snap-trapped in a mature conifer forest, unburned clearcuts, and burned clearcut in
the western Cascade Mountains in central Washington. The largest populations were in unburned
clearcuts, and the smallest overall population was in the forest. Sorex trowbridgii was the most abundant
insectivore caught. Clethrionomys gapperi was the most abundant rodent caught in most clearcuts, and its
population was the largest of any species in the study area. Vegetation and percent cover were analyzed in
the study area, and small mammal stomach contents of all nine animal species were examined. In the
forest and burned clearcut, small mammals ate more invertebrates than any other food type. In unburned
clearcuts, fungi and ephiphytic lichens and conifer seeds were the major foods eaten by rodents.
Top of Document
DOCUMENT #36
Small Mammals and Reforestation Following Prescribed Burning
CITATION:
Ahlgren, C.E. 1966. Small mammals and reforestation following prescribed burning. Journal of Forestry. 64: 614-618.
KEYWORDS\CONCEPTS: Soil moisture, ecological factors, microbial populations, burning, deer mice,
reproduction, trapping.
ABSTRACT:
Changes in populations of small mammals were investigated on four jack pine tracts in northeastern
Minnesota. One tract was left uncut, one was cut with slash evenly distributed, and two were cut and
subjected to controlled burning. North American census trapping methods were used in July and October
for three consecutive years. Populations of deer mice were significantly higher on burned tracts than on
unburned tracts the first and third post-fire years. This increase was related to the supply of seed released
by burned jack pine and also other seed exposed in the upper layers of soil, as well as to cover conditions.
Since burning created habitat and food conditions favorable to the increase of seed eating mouse species
they must be taken into consideration in post-fire reforestation.
Top of Document
DOCUMENT #37
Small Mammals in old Field Succession
CITATION:
Hirth, Harold F. 1959. Small Mammals in old Field Succession. Ecology. 40: 417- 425.
KEYWORDS\CONCEPTS: Successional stages, strip mines, floodplains, tree ring counts, vegetational
succession.
SYNOPSIS:
The purposes of this study were to examine small mammal populations in upland old field successional
stages in New England during the different seasons in one year and to evaluate biotic and other
environmental factors in the successional series that affect these populations.
Top of Document
DOCUMENT #38
Input and decay of coarse woody debris in coniferous stands in western Oregon and
Washington
CITATION:
Sollins, P. 1981. Input and decay of coarse woody debris in coniferous stands in western Oregon
and Washington. Can. J. For. Res. 12: 18-28.
KEYWORDS\CONCEPTS: Conifer forests, tree mortality, topographic features, Douglas-fir.
ABSTRACT:
The decay rate at the old-growth stand, calculated indirectly by dividing bole mortality of fallen and
standing dead woody material was 0.028 year. This rate, three to five times those previously calculated
directly from change in density alone, was almost identical to values calculated elsewhere from change in
both volume and density. Decay rates based on change in density alone include only respired and leached
material and exclude the large amount of material lost in fragmentation. This study shows the value of
permanent plots, undisturbed by salvage logging, for retrospective studies of decomposition, nutrient
cycling and productivity.
Top of Document
DOCUMENT #39
Ecology of Coarse Woody Debris in Temperate Ecosystems
CITATION:
Harmon, M.E., et al. 1986. Ecology of Coarse Woody Debris in Temperate Ecosystems, Advances in
Ecological Research, Volume 15, pp. 133-302.
KEYWORDS\CONCEPTS: Temporal patterns, agents of mortality, decomposition, decay, biomass,
plant habitat, animal habitat, nutrient cycles, ecosystems, aquatic, terrestrial, carbon budgets.
SYNOPSIS:
This article partially parallels the structure of a forest-ecosystem compartment model. Coarse Woody
Debris in a temperate forest and stream ecosystems is emphasized and includes only selected references on CWD in tropical and boreal ecosystems for comparative purposes. In Section II, the rate at which CWD is added to ecosystems via tree mortality and breakage of stems and branches, as well as by physical transport from adjacent ecosystems, is considered. As soon as CWD is created, biological and physical processes begin to degrade it. Section III examines the processes involved in decay and decomposition rates of CWD. Of these, respiration and fragmentation have received most study, whereas leaching, burial and physical transport have received least. In Section IV, rates of tree death and decomposition is examined as well as disturbances to forests control the amounts of CWD in temperate ecosystems. The functional importance of CWD depends not only on the amount of CWD, but also on its distribution is terms of size, spatial arranfgement, degree of decay, species, and
position (i.e. snags versus logs). In Section V the focus is on the influence that CWD exerts on organisms
and processes within ecosystems, as a plant, vertebrate, and invertebrate habitat, as well as its role in
nutrient cycles and in controlling geomorphic processes. The ecological behavior and significance of
CWD varies markedly between aquatic and terrestrial environments and between managed and "natural"
lands. The article concludes with a comparison of these environments.
Top of Document
Contact Shane
Ford if you have comments on the presentation of this information.
Ministry of Forests
Forest Practices Branch
PO Box 9513 Stn. Prov. Govt.
Victoria, BC
V8W 9C2
Phone: (250) 387-1310
Fax: (250) 387-1467
Last modified May 30, 2001
|
