Changes in Understory Production Following a Wildlife in Southwestern Ponderosa Pine

Abstract

An area burned by a May, 1972, wildfire and which had been previously sampled in 1972 and 1974 was remeasured in 1980 to determine changes in understory production. The area was stratified into moderately and severely burned areas. By 1974 both herbage and forage production on the moderately burned area were approximately 3 times higher than unburned control sites and did not decline significantly by 1980. While increased herbage production on the severely burned site was similar to that of the moderately burned site in 1974, it declined to only half as much production by 1980. Furthermore, while over 95% of the total herbage production was in forage species for all 3 sampling years on the moderately burned study area, only 30 percent was forage on the severely burned study area by 1980. The decline in total production and shift to non-forage species on the severely burned study area is probably a consequence of heavy grazing which followed the burn.