Responses of Vegetation and Ground Cover to Spraying a High Elevation, Big Sagebrush Watershed with 2,4-D

Abstract

Total production of aboveground biomass on a 238-ha watershed was not affected when big sagebrush (Artemisia tridentata) was controlled by aerial application of 2,4-D (2,4-dichlorophenoxyacetic acid). Grass production increased in the 5 years following treatment, but forb production was not affected by treatment because forbs were in an early phenological stage when sprayed. Five years after treatment, there was a 37% decrease in bare ground, and a 29% and 61% increase in litter and grass cover, respectively, on the treated watershed compared to an adjacent untreated watershed.