Woody Detritus Density and Density Reduction Factors for Tree Species in the United States

Woody detritus biomass estimates are most often achieved by determining the volume of dead wood and then converting to mass by use of density values. There have been few studies on how density (mass/volume) of this material changes during the decay process. The goal of this study was to synthesize both published and unpublished data on woody detritus density so as to improve estimates of coarse woody detritus (CWD) and fi ne woody detritus (FWD) biomass across the diverse forests of the United States. In the case of CWD, a total of 88 species were found to have data on densities for fi ve decay classes that had been published and/or collected in North America from the boreal to the tropical zones. In general, density declined from decay class 1 to 5 with at least fi ve density reduction patterns observed. For FWD, our search indicated approximately 25 species had been sampled.