Chemical Control of Sorghum halepense in Home Lawns Across Two Different Mowing Heights

Sorghum halepense [L.] Pers. (johnsongrass) is a common perennial grassy weed found throughout the southern United States. While not considered a common weed in home lawns, Sorghum halepense encroachment does occur in newly constructed neighborhoods developed on old pasture lands. Limited published research regarding Sorghum halepense control in home lawns is available even though several herbicides are labeled for Sorghum halepense suppression or control. Therefore, experiments were conducted to examine different combinations of application rates and/or frequencies of fenoxaprop, fluazifop, and topramezone for Sorghum halepense control in tall fescue swards. In addition to examining herbicidal control of Sorghum halepense, weekly mowing heights of 2.5 or 8.9 cm were applied. Fenoxaprop applied at 0.10 kg a.i. ha^-1 for two or three sequential applications or fluazifop at 0.10 kg a.i. ha^-1 resulted in the greatest Sorghum halepense control. A single application of fenoxaprop and all application rates and frequencies of topramezone did not reduce Sorghum halepense compared to controls. Mowing height had no significant effect on Sorghum halepense control.