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| | Tools and Links Biomass Harvesting Guidelines Discussion ^ Dead wood plays an important role in the ecosystem from wildlife habitat to carbon storage. - Rodents, shrews, carnivores, salamanders, turtles and snakes all rely on dead wood for habitat.
- Birds use standing dead trees to build nests, search for insects, and as a hunting perches. As many as 40% of forest birds depend on tree cavities (Hunter 1990) .
- Logs that fall in the water form critical component of aquatic habitat by ponding water and storing sediments (A. M. Gurnell 1995).
- Amphibians live in and around downed logs. Retention of CWD may play a role in mitigating some of the effects of clearcutting on amphibians (Patrick et al. 2006).
- Dead logs serve a seed bed for tree and plant species (McGee 2001)
- Fungi depend on dead wood for nutrients and moisture and in turn many trees rely on mutualistic relationships with ectomycorrhizal fungus (Hagan and Grove 1999).
- Dead wood slowly releases nutrients back to the soil and the forest.
- Nitrogen fixation in coarse woody material an important source of this limiting element in both terrestrial and aquatic ecosystems (Harmon et al. 1986).
- Woody material on the ground decreases water runoff and erosion.
- About 6% of carbon is stored in forests is in dead wood (Environmental Protection Agency 2007).
In general, northern forests have less dead wood in them now then before Europeans arrived. Old growth forests tend to have more logs, snags, and other dead wood than managed or younger forests. For example, old growth hemlock-hardwood forests in the Adirondack park have a greater volume of coarse woody debris, both snags and logs, than second growth stands (Ziegler 2000). While dead wood accumulates in forests it doesn't last forever. On average snags typically last about 10 years, while logs last twice that long (Harmon et al. 1986). Although in the Hubbard Brook Experimental Forest in New Hampshire, snags and coarse woody debris had residence times of 15, and 6.2 years, respectively (Siccama et al. 2007). Timber harvests tend to increase the amount of dead wood on the ground as branches, tree tops, and small trees are left after the large, more valuable trees are removed. The amount of dead wood on the ground generally increases with the intensity of the harvest (Park et al. 2005, Li et al. 2007). Harvesting approaches can be designed to increase dead wood and other old growth characteristics (Keeton 2006). While an intensive harvest such as a patch cut may produce a large amount of dead wood in the short term, it also leaves few trees to die and become dead wood in the future. Moreover, as utilization (the amount of wood from the forest used) increases, intensive harvests can reduce both the amount of dead wood in both the short and long term.
1 A. M. Gurnell, K. J. G., G. E. Petts,. 1995. The Role of Coarse Woody Debris in Forest Aquatic Habitats: Implications for Management. Aquatic Conservation: Marine and Freshwater Ecosystems 5(2):143-166.
http://dx.doi.org/10.1002/aqc.3270050206
2 Environmental Protection Agency. 2007. Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2005. USEPA #430-R-07-002, Washington, DC.
3 Hagan, J. M., and S. L. Grove. 1999. Coarse Woody Debris: Humans and Nature Competing for Trees. Journal of Forestry 97(1):6-11.
http://www.ingentaconnect.com/content/saf/jof/1999/00000097/00000001/art00006
4 Harmon, M. E., J. F. Franklin, F. J. Swanson, P. Sollins, S. V. Gregory, J. D. Lattin, N. H. Anderson, S. P. Cline, N. G. Aumen, J. R. Sedell, G. W. Lienkaemper, K. Cromack Jr., and K. W. Cummins. 1986. Ecology of Coarse Woody Debris in Temperate Ecosystems
Advances in Ecological Research. Pages 133-302 in A. M. a. E. D. Ford, editor. Academic Press.
http://www.sciencedirect.com/science/
5 Hunter, M. L. 1990. Wildlife, Forests, and Forestry. Prentice-Hall, Englewood Cliffs, NJ.
6 Keeton, W. S. 2006. Managing for Late-Successional/Old-Growth Characteristics in Northern Hardwood-Conifer Forests. Forest Ecology and Management 235(1-3):129-142.
http://dx.doi.org/10.1016/j.foreco.2006.08.005
7 Li, Q., J. Chen, D. L. Moorhead, J. L. DeForest, R. Jensen, and R. Henderson. 2007. Effects of Timber Harvest on Carbon Pools in Ozark Forests. Canadian Journal of Forest Research 37(11):2337–2348.
http://dx.doi.org/10.1139/X07-086
8 McGee, G. G. 2001. Stand-Level Effects on the Role of Decaying Logs as Vascular Plant Habitat in Adirondack Northern Hardwood Forests. The Journal of the Torrey Botanical Society 128(4):370-380.
9 Park, B. B., R. D. Yanai, and R. H. Germain. 2005. Effects of Silvicultural Treatments on Coarse Woody Debris in the Catskill Region. in L. S. Kenefic and M. J. Twery, eds., editors. Changing Forests - Challenging Times: Proceedings of the New England Society of American Foresters 85th Winter Meeting. GTR-NE-325. USDA Forest Service. Northeastern Research Station, Newtown Square, PA.
http://www.nrs.fs.fed.us/pubs/6810
10 Patrick, D. A., J. Hunter, Malcolm L., and A. J. K. Calhoun. 2006. Effects of Experimental Forestry Treatments on a Maine Amphibian Community. Forest Ecology and Management 234(1-3):323-332.
http://www.sciencedirect.com/science/
11 Siccama, T. G., T. J. Fahey, C. E. Johnson, T. W. Sherry, E. G. Denny, E. B. Girdler, G. E. Likens, and P. A. Schwarz. 2007. Population and Biomass Dynamics of Trees in a Northern Hardwood Forest at Hubbard Brook. 37(4):737–749.
10.1139/X06-261
12 Ziegler, S. S. 2000. A Comparison of Structural Characteristics between Old-Growth and Postfire Second-Growth Hemlock-Hardwood Forests in Adirondack Park, New York, U. S. A. Global Ecology and Biogeography 9(5):373-389.
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