Dead and down woody material (logs, stumps, limbs and upturned tree roots) in various stages of decay serves many critical functions.
Dead and down woody material, often referred to as coarse wood material (CWM) or coarse woody debris, is important for nutrient retention and cycling, as nurse logs for regenerating trees and understory plants, and as wildlife habitat. Large (18+ inches) hollow or rotten logs and stumps generally have the greatest value. Softwood stands usually contain more and longer-lasting down woody material than hardwood stands. Maintaining snags and cavity trees will also serve to maintain CWM, as these trees eventually fall over.
Coarse woody material is used by more than 30 percent of the region's mammals, 45 percent of the amphibians, and 50 percent of the reptiles. It's used as a feeding site by rodents, shrews, black bears, and woodpeckers and provides shelter for many small mammals. Seventeen mammal species, including black bear, otter, mink, fisher, weasels, and deer mouse either den or hunt in or under downed logs. CWM creates moist microhabitats used by amphibians. Downed logs create pools and riffles in streams that provide important fish habitat, as well as basking and nesting locations for turtles, waterfowl, mink, and otter. Several ground-nesting birds (including juncos and winter wrens) nest in upturned tree roots. Dead and down woody material provides habitat for many other organisms including insects and other invertebrates, mosses, fungi, and lichens.
Manage for coarse woody material by retaining material that currently exists and allowing its accumulation where it is missing.
2.2 Forest Structure; 3.1 Timber Harvesting Systems; 3.2 Logging Aesthetics; 4.2 Wetlands; 4.3 Forest Management in Riparian Areas; 4.4 Stream Crossings and Habitat; 5.3 Ice and Wind Damage; 6.2 Cavity Trees, Dens and Snags; 6.4 Overstory Inclusions.
DeGraaf, R., M. Yamasaki, W. B. Leak, and A. M. Lester. 2006. Technical Guide to Forest Wildlife Habitat Management in New England. University of Vermont Press and University Press of New England, Burlington, Vt. 305 p.