14. Coarse Woody Debris – Some Recommendations Made
386. Public perception as messy logging that wastes wood has influenced
CWD management. This has led to a policy of 'zero waste tolerance.'
The importance of CWD in stream ecosystems and the role of snags are more
widely accepted. Management requires increased understanding of its importance
in the forest management arena, the environmental community, and the general
public (Voller and Harrison, 1998).
387. Future forests will contain much less coarse woody debris (CWD),
and that debris will be smaller and of different quality than that seen today.
We have the technology to remove most coarse woody debris from the forest;
in fact, current wood utilization standards encourage such removal.
Moreover, converting natural forests to intensively manipulated stands reduces
tree life spans from centuries to decades; future trees will be much smaller
than they are today, and wood quality will undoubtedly be different from
that of today’s forests (Maser, Tarrant, Trappe and Franklin, 1988,
pg25-par3).
388. Forest floor diversity is partly maintained by windthrown trees
that create a pit-and-mound topography as they are uprooted (Maser, Tarrant,
Trappe and Franklin, 1988, pg45-fig.2.7).
389. NOTE Class system chart is on Page 32 (Maser, Tarrant, Trappe
and Franklin, 1988).
390. Certainly our knowledge of biological processes and their interactions
within forest is incomplete, and we know too little about the cumulative
effect of a wide range of stresses on the ecosystem. But integrative
research at the ecosystem level shows clearly that the many processes operating
within forest inter-connect in important ways. Further, diversity of microscopic
and macroscopic plant and animal species is a key factor in maintaining these
processes (Maser, Tarrant, Trappe and Franklin, 1988, pg1-par2).
391. Forest managers need to know what actually happens in order to
plan harvests that will protect essential element and nutrient cycles and
streams from low pH precipitation (Hornbeck, 1992, page 151).
392. With the latter information known, we need to know more about
the fallen trees contribution to the forest as a whole and to the quality
of the soil in particular (Maser and Trappe, 1984, pg49-par1).
393. Managers, of once fertile forest, need to know how the system
will benefit from fallen trees over the long run (Maser and Trappe, 1984,
pg48-par2).
394. The physical qualities of a fallen tree – moisture, temperature,
essential element content, and pH are likely to change markedly with so called
but poorly defined “stand removals, regeneration, reforestation and so called
regrowth” (Maser and Trappe, 1984, pg49-par1). Note, especially when they are
removed.
395. Recent and current research in Old-growth forest are revealing
much about the roles and qualities of fallen trees. Understanding this
information may allow use of fallen trees as sensitive barometers of “habitat
health” of a system (Maser and Trappe, 1984, pg49-par1).
396. Large, fallen trees are unique, critical, dynamic components of
forests (Maser and Trappe, 1984, pg1-par2).
397. Up to a century ago western stream systems also characteristically
contained abundant pieces and aggregations of large, woody debris, but that
debris has been systematically removed to improve navigation, flood control,
and drainage. We now have the technological capability to remove more and
more woody debris from the forest floor. Conversion of forests from virgin
to managed status reduces rotation ages from centuries to decades with a
consequent reduction in average size of trees and change in wood quality
(Maser and Trappe, 1984, pg1-par4).
398. Coarse woody debris can be incorporated into the surface soil
horizon as freezing and thawing cycles move CWD into the soil. Additionally,
CWD can be covered as soil moves downhill. Depending on the forest type,
large amounts can be left in the form of decaying tree roots. All of
these materials, in the advanced stages of decay, can be active parts of
the soil system as soil wood. (Carbon Based Cellulose) Because CWD is an
important component of a functioning ecosystem, a portion of this material
must be maintained. As the demand for forest products and the ability to
utilize more fiber increases, less material is being left after timber harvesting
or after salvage operations. These operations, in combination with past practices
of slash disposal and site preparation, have reduced organic material in
the forest floor, making CWD management critical (Harvey and others 1987).
Consequently, recommendations for maintaining CWD for different ecosystems
and forest types are needed (Graham, Harvey, Jurgensen, Jain, Tonn and Page-Dumroese,
1994).
399. Obviously, not all of the organic matter in the forest floor is
derived from CWD; some is derived from foliage, fine woody material, or other
organic components. Harmon and others (1986) summarized the few studies showing
the contribution to the forest floor and found it to range from 24
to 74 percent. Our past work showed that CWD contributed up to 58 percent
of the organic materials to the forest floor; in this study CWD contributed
up to 100 percent of the organic materials. Because of this variation, the
range of 25 to 50 percent seemed suitable and conservative for the sites
we sampled in the Rocky Mountains (Graham, Harvey, Jurgensen, Jain, Tonn
and Page-Dumroese, 1994). Question: What percentage of organic matter
is added by CWD in old growth areas in the ANF? What bio-indicator
was used to determine the amount of CWD needed for the functionality of the
systems parts and processes with respect to soil, fauna and flora survival?
400. Ectomycorrhizae absorb moisture and essential elements, and translocate
them to their host plants, making ectomycorrhizae essential for the development
of such ecosystems (Harley and Smith 1983; Harvey and others 1979; Harvey
and others 1987; Marks and Kozlowski 1973; Maser 1990). Therefore, we assume
their presence and abundance to be a good indicator of a healthy, functioning
forest soil. Ectomycorrhizae have a strong positive relationship with soil
organic materials (Harvey and others 1981). Soil wood, humus, and the upper
layers of mineral soil that are rich in organic matter are the primary substrates
for the development of ectomycorrhizae. (Graham, Harvey, Jurgensen, Jain,
Tonn and Page-Dumroese, 1994).
401. Further more, woody debris is one of the slowest components of
the ecosystem to recover after disturbance. Therefore, short intervals between
timber harvests can reduce ecosystem carbon storage in coarse woody debris
even when the living portion of the ecosystem has recovered. Conversely,
allowing debris to accumulate would result in more carbon, being stored in
the ecosystem than has been predicted by current projections, which assume
that a steady state is reached in less than 100 years (Harmon and Hua, 1991).
402. Past efforts at estimating global detrital storage (including
duff, coarse woody debris, and soil organic matter) have assumed that only
a small fraction of carbon is stored in coarse woody debris. This assumption,
at least for old-growth forests, is a mistake. Given the tack of data on
the mass of coarse woody debris in various biomes, global carbon storage
in woody debris cannot yet be directly estimated (Harmon and Hua, 1991).
403. Studies of a forest containing Fagus – Betula in New England have
29% of the total detritus in coarse woody debris. A forest containing trees
of the Quercus species has been noted to have 9%. More than half the
total detritus (54%) at Andrews in Coarse Woody Debris (Harmon and
Hua, 1991).
404. Models of forest recovery that exclude symplastless wood do not
account for the substantial amount of carbon that is being absorbed by recovering
forest in the later stages of succession. (Harmon and Hua, 1991).
405. Preservation of a threatened or endangered species involves preservation
of its habitat and the diversity that habitat entails. When such becomes
a goal of forest management, managers need information not only on owls or
small mammals, but also on the mycorrhizal fungi that form the base of the
food web. Removal of ectomycorrhizal tree hosts removes the energy
source of ectomycorrhizal fungi, which will not fruit without their host
plants (Amaranthus, Trappe and Bednar, 1994).
406. Fungal diversity has usually been overlooked in considerations
of the management of forest. The more obvious plants and animals attract
the attention of the casual observer, but foresters and ecologists need to
recognize that the health of the forest depends on organisms and processes
below ground (Amaranthus, Trappe and Bednar, 1994).
407. Data shows leaving materials behind with soil contact is what
is needed for once fertile forest health and not removal of such (Amaranthus,
Trappe and Bednar, 1994).
408. NATIONAL WOOD FIBER NEEDS indicate substantial increases in demand
for wood fiber - based products. This demand has resulted in increased efforts
to remove all available fiber at harvesting sites. Intensive fiber removal
or intense wildfire potentially reduces the parent materials (duff and wood
residues) available for the production of organic reserves in forest soils.
This reserve, primarily in the form of humus, decayed wood, and charcoal,
has been shown critical to the support of both nonsymbiotic nitrogen fixing
and ectomycorrhizal activities in forest soils of western Montana.
Harvest and fire-caused reductions of organic materials on and in northern
forest soils have been linked to reforestation problems. This study was undertaken
to provide a preliminary estimate of the impact of varying amounts and kinds
of soil organic matter on ectomycorrhizal development in mature western Montana
forests (Harvey, Jurgensen and Larsen, 1981).
409. Both season and site affect the relation between the number of
active ectomycorrhizae and soil organic matter in these ecosystems. In the
dry season or on the drier site, the high soil organic matter content yielded
larger numbers of active ectomycorrhizae than did the low organic matter
conditions. Forest management decisions with potential to disturb soils and
reduce woody residues, particularly in dry Northern Rocky Mountain habitat
types, should take into consideration the importance of soil organic reserves
and their affects on ectomycorrhizae as a factor in forest soil quality.
A consistent effort should be made to retain a moderate quantity of large
woody materials. Preliminary estimates indicate that approximately 25-37
tons/hectare (Harvey, Jurgensen and Larsen, 1981).
410. Evidence that soil organic reserves, particularly wood, play important
roles in maintaining forest site quality emphasizes the need to properly
manage woody materials. Thus, the viewpoint that woody residue represents
only waste or a fire hazard must be reassessed. Forest users and managers
must recognize the benefits, equivalent to long-term fertilization, which
woody and other organic reserves contribute to forest ecosystems (Maser and
Trappe, 1984, pg1-par3).
411. Woody debris is generally removed from streams or forests in the
name of economic progress, but what are the short-term and long-term biological
consequences? (Maser and Trappe, 1984, pg1-par5)
412. How is habitat diversity affected, and what is the impact on long-term
site productivity? (Maser and Trappe, 1984, pg 1-par5)
413. Forests of the future will have far less woody material contributed
to the forest floor than forests of the past, and that material will differ
in size and quality from the woody debris that has been historically prominent
in forest habitats (Maser and Trappe, 1984, pg1-par4).
414. Large, fallen trees in various stages of decay contribute much-needed
diversity to terrestrial and aquatic habitats in western forests. When most
biological activity in soil is limited by low moisture availability in summer,
the fallen tree-soil interface offers a relatively cool, moist habitat for
animals and a substrate for microbial and root activity. Intensified utilization
and management can deprive future forests of large, fallen trees. The impact of
this loss on habitat diversity and on long-term forest productivity must be
determined because management need sound information on which to base
resource management decisions (Maser and Trappe, 1984, Abstract-par2).
415. Decaying trees comprise considerable accumulations of mass, nutrients
and elements in unmanaged, old growth forest. Some of the largest accumulations
occur in the unmanaged forest of the Pacific Northwest. Coarse woody debris
can range from 130 to 276 tons per acre in stands from 100 to more than 1,000
years old. Although here we are concerned with Douglas fir, neither decaying
wood nor research data are unique to forests of the Pacific Northwest.
McFee and Stone ( 1966) Observed that decaying wood persisted for more than
100 years in New York and others pointed out that substantial accumulations
in old-growth forest in Poland. These observations evidence the long-term
continuity of decaying trees as structural components in forest (Maser and
Trappe, 1984, pg 16-par1).
416. Please note that other recommendations are provided with respect
to streams, water, oceans, wetlands, etc. in several docs, one being (Maser,
Tarrant, Trappe and Franklin, 1988).
417. In New England, intensive harvesting (wood removal) in the form
of whole-tree clearcutting results in important losses of plant essential
elements such as Ca, K, and N. Shortages of plant-available essential
elements might develop in regenerating stands, particularly in the years
immediately after harvest when leaching losses and plant uptake are high.
Net losses in input-output budgets and preferential uptake by trees for essential
elements such as Ca suggest that there also could be essential element limitations
during future rotations. Until these concerns are researched more carefully,
whole-tree clearcutting should be applied with caution (Hornbeck et al.,
1990, page 63)
418. Checklist of plants and animals. There are few checklists of either
plants or animals that inhabit fallen Douglas fir in Pacific Northwest. [Let
alone, in other areas with other species, in the USA – (Termed as profiles
or unique features)]. No checklist of the microorganisms in fallen
trees of western old-growth forest is available [I know of none in the east.];
the subject has hardly been studied. (Higher fungi have been cataloged
for many kinds of so-called rotten wood in Europe.) Lawton listed the
mosses that occur on so called rotten wood or stumps in the Pacific Northwest.
Deyrup (1975, 1976) has done a thorough job with insects and has identified
about 300 species associated with fallen Douglas fir. The only published
checklist for vertebrates that use fallen trees is for northeastern Oregon
(Maser and others 1979 not listed in references here). (Maser
and Trappe, 1984, page 18-par 2)
420. Conclusion: What parts and processes of this once fertile
forest were knowingly sacrificed to the mere interest of production of board
foot and or lumber degrade factors?
What were the tools, indicators, used to understand these parts and processes?
What was the major factor to determine one to be sacrificed?
In summation, we must not sacrifice the options of future generations on
the altar of cost-effectiveness through decisions based on insufficient data.
It is the professional charge of researchers to obtain the needed data and
of managers to apply it (Maser and Trappe, 1984, pg49-par3).
421. The USFS claims to foster concepts of tree biology in old growth areas.
Does this mean they claim to have no responsibility to flora and fauna here
in this “Burn and Clearcut Project”?
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