Cultivation Legacy Effects On Vegetation Structure and Plant Community Composition Following Shrub Reduction in Utah
Location
USU Eccles Conference Center
Abstract
We studied big sagebrush plant community responses to a two-way chain harrow and broadcast seeding of herbaceous species at eight Wyoming big sagebrush sites with the same ecological site classification; five were cultivated for dryland wheat production during the 1950-1980s, then seeded with introduced forage grasses and reverted back to grazing lands, while three had not been previously cultivated. Five years after treatment, densities of sagebrush seedlings and snakeweed plants increased in cultivated sites during the second and third year after treatment. In addition, perennial forb cover increased for cultivated sites, while perennial grass biomass increased for non-cultivated sites. Plant community change after treatment also varied between non-cultivated and cultivated sites, and response to treatment was most strongly correlated with reductions in sagebrush cover, increases in the perennial grass bulbous bluegrass, and increases in 10 herbaceous species—four of which were seeded. Our results emphasize that broad variability in plant community responses to sagebrush reduction is possible within the same ecological site classification, and that cultivation history can leave long- lasting legacy effects.
Cultivation Legacy Effects On Vegetation Structure and Plant Community Composition Following Shrub Reduction in Utah
USU Eccles Conference Center
We studied big sagebrush plant community responses to a two-way chain harrow and broadcast seeding of herbaceous species at eight Wyoming big sagebrush sites with the same ecological site classification; five were cultivated for dryland wheat production during the 1950-1980s, then seeded with introduced forage grasses and reverted back to grazing lands, while three had not been previously cultivated. Five years after treatment, densities of sagebrush seedlings and snakeweed plants increased in cultivated sites during the second and third year after treatment. In addition, perennial forb cover increased for cultivated sites, while perennial grass biomass increased for non-cultivated sites. Plant community change after treatment also varied between non-cultivated and cultivated sites, and response to treatment was most strongly correlated with reductions in sagebrush cover, increases in the perennial grass bulbous bluegrass, and increases in 10 herbaceous species—four of which were seeded. Our results emphasize that broad variability in plant community responses to sagebrush reduction is possible within the same ecological site classification, and that cultivation history can leave long- lasting legacy effects.