Forty Years Of Prescribed Burning On The Santee Fire Plots: Effects On Understory Vegetation
The effects of 43 years of repeated prescribed burning on crown cover, species composition, species richness, and diversity in the lower understory strata of the Santee Fire Plots were examined. Five study treatments, installed in 1946, include an unburned control, periodic winter and summer bums, and annual winter and summer bums. Understory cover has not changed in the past 20 years except in the annual winter bum plots where cover of trees < 1.5 m in height declined and grass cover increased. Detrended correspondence analysis indentitied four distinct understory plant communitites corresponding to season and frequency of bum. Distribution of understory species across a tire disturbance gradient is discussed in terms of varying plant adaptations to tire. Species richness, when separated into herbaceous and woody species groups, and Shannon's diversity index varied significantly across treatments.