Glyphosate for Johnsongrass (Sorghum halepense) Control in No-Till Sorghum (Sorghum bicolor)

Abstract

Field experiments were conducted to evaluate johnsongrass control in no-till grain sorghum with glyphosate treatments applied in mid-June, late July, and mid-September before planting grain sorghum the following spring. Mid-June applications provided the best johnsongrass control. Ammonium sulfate enhanced the activity of glyphosate for only the late-July applications. In separate experiments, herbicide systems comprised of fall applications of glyphosate and/or spring applications of foliar and residual herbicides were evaluated. Fall applications of glyphosate provided superior johnsongrass control and grain sorghum yields.