Silverleaf Nightshade (Solanum Elaeagnifolium) Control in Cotton with Glyphosate at Reduced Rates

Abstract

Silverleaf nightshade is a pernicious perennial weed that reduces lint yield and quality on thousands of cotton hectares on the southern High Plains of Texas and in southwestern Oklahoma. Field experiments were conducted in 1992 and 1993 to evaluate silverleaf nightshade control with glyphosate applied at low rates during the previous fall. Glyphosate at the labelled use rate of 1.7 kg ha^-1 gave 97% control of silverleaf nightshade approximately one year after application. Glyphosate at rates of 0.8, 1.1, 1.3 and 1.5 kg ha^-1 provided similar control.