Antagonism of Johnsongrass (Sorghum halepense) Control with Fenoxaprop, Haloxyfop, and Sethoxydim by 2,4-D

Johnsongrass control in the field was greater with fenoxaprop or haloxyfop than with sethoxydim in 1985 and 1986. Johnsongrass control was reduced under field and greenhouse conditions by adding a dimethylamine salt of 2,4-D. Generally, the antagonism was overcome by increasing the rate of fenoxaprop, haloxyfop, or sethoxydim. Sethoxydim showed less antagonism from 2,4-D than did fenoxaprop or haloxyfop in the greenhouse.