Field studies were conducted in 1990 and 1991 to evaluate johnsongrass control and interference in corn using combinations of nicosulfuron, EPTC + dichlormid, and cultivation. Nicosulfuron applied to 30-cm-tall rhizome johnsongrass provided greater control and corn yield than a later application to 60-cm-tall johnsongrass. Johnsongrass control and corn yield within the later nicosulfuron treatment were improved by a preplant application of EPTC. EPTC and/or cultivation alone provided less johnsongrass control and lower corn yield than nicosulfuron or handweeding.
