Shrub control and seeding influences on grazing capacity in Argentina.

Abstract

Total vegetation cover, forage species cover, litter cover, and carrying capacity were determined during 3 growing seasons (1979-80, 1980-81, and 1981-82), for plots cleared of shrubs with or without sowing of native grasses in a site characteristic of the Monte Phytogeographical Province in mid-west Argentina. We tested the hypothesis that shrub removal with or without sowing of native grasses increases aerial cover of forage, especially species capable of quick establishment ("pioneers"), that ultimately results in a greater carrying capacity. When shrubs were removed and the cut material was left on the soil surface, average cover of forage species increased 156% over the control at the end of the third growing season. Increased carrying capacity (229%) also resulted from shrub control on the study area. Sowing with grasses produced a response in only 1 species. Thus, shrub control with or without additional sowing of native grasses appears capable of improving the carrying capacity of shrub communities of low forage value, typical of this temperate arid zone.