Range Productivity as Influenced by Biennial Sweetclover in Western South Dakota

Abstract

Biennial sweetclover was seeded into a Dense Clay Range Site that was severely depleted by drought and overgrazing. Seeded in 1962 without seedbed preparation, sweetclover has reseeded naturally, and remained a compatable associate with the native vegetation during the five-year study. Combined grass and sweetclover production averaged 1804 lb/acre annually compared to 750 for the control. The grass component was increased by an average of 373 lb/acre as a result of legume supplied nitrogen. Western wheatgrass vigor and forage protein were also improved. Native perennial grasses were not reduced in abundance by sweetclover competition. Sweetclover appears well adapted as a legume for rangelands with heavy clay soils in western South Dakota.