Notes: Decay and Dynamics of Snags in the Sierra Nevada, California
A study on the rates of decay, falling, and recruitment in a population of snags (standing dead trees) in the Sierra Nevada, California, during 1975-83 showed that large-diameter (>38 cm dbh) snags fell slower than small-diameter snags. Firs (Abies spp.) fell at a lower rate than pines (Pinus spp.). Snags lost all needles and twigs within five years; 75% of pines and 66% of firs had lost most larger limbs within five years. Compared with the numbers of live trees in the parent stand, rates of new mortality were highest among Jeffrey pine (Pinus jeffreyi Grev. and Balf.) <15 cm dbh. Live-tree morality exceeded the rate that snags fell during our study, causing an increase in the snag population from 1978 to 1983. A Leslie matrix model of this snag population was developed that accounted for falling rates, transitions among decay stages, and recruitment of snags. Use of the model was illustrated using field data from five unburned study plots. For. Sci. 33(3):774-783.
No Supplementary Data
No Article Media