Author: Nathan Wade

Publisher:

Published: 2022

Total Pages: 0

ISBN-13:

Fire exclusion, climatic change, and mismanagement have led to woody shrub encroachment and exotic species invasions on rangelands. The impacts of fire and fire seasonality (fall and spring) on black greasewood (Sarcobatus vermiculatus, Hook., Torr.) survival, density, structure, and plant communities were studied. The impact of an integrated fire-herbicide treatment was also examined on greasewood survival, density, and structure. Research was conducted at two greasewood-dominated sites, in Miles City, MT, USA and in Laramie, WY, USA. The MT site was dominated by C3 exotic grasses, and the WY site was dominated by C4 native grasses. Fire, regardless of season and site, did not impact shrub survival and density, but decreased shrub volume for a predicted 4 – 5 years. Fire, regardless of season or site, also had no impact on native or exotic plant abundance. Current-year biomass increased in spring burns in MT and decreased in spring burns in WY. With fire-herbicide treatments, 4 treatments were studied (control, fall burn, herbicide, and fall burn with herbicide). Both herbicide treatments had the lowest survival rates, with herbicide alone being the lowest. Shrub density, height, canopy area, and volume were lowest in both herbicide treatments. Shrub volume was predicted to take >10 years after herbicide application to recover. Besides shrub survival, there were no differences in shrub density and structure between the two herbicide treatments. Greasewood is resilient and future studies can investigate the impact of repeated fire and herbicide treatments on greasewood and associated plant communities.