Disappearance of dead plant material in a mixed grass prairie.

Disappearance of dead plant material was studied in ungrazed mixed grass prairie in Western North Dakota. Disappearance rates varied both within and between years as well as with method used. The highest rates (2.07 to 3.15 g/m2/day) were recorded early in the season and disappearance continued during the winter but at a slower rate (0.99 g/m2/day). Some differences were found in rates of disappearance of dead material of different species during the first two months. Annual decomposition rates ranged from 400 g/m2 to 526 g/m2. The ash content of dead material showed generally increasing values with advancing decomposition. The turnover time of above-ground biomass appeared to be approximately three years.