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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