Soft rush is a perennial, tussock-forming plant that often infests low-lying grazing areas in Florida. Experiments were conducted to determine the most effective herbicides for control of soft rush. Herbicide treatments included triclopyr fluroxypyr at 0.43 0.15 and 0.86 0.30 kg/ha, 2,4-D amine at 1.12 and 2.24 kg/ha, 2,4-D amine carfentrazone at 1.12 0.02 and 2.24 0.02 kg/ha, aminopyralid at 0.12 kg/ha, and 2,4-D amine dicamba at 1.61 0.56 kg/ha and were applied to soft rush with and without mowing to a 15-cm stubble height. Aminopyralid and triclopyr fluroxypyr did not control soft rush with or without mowing 1 and 12 mo after treatment (MAT). When mowing occurred prior to application, treatments containing 2,4-D provided at least 81% control of soft rush 1 MAT. In contrast, control was no greater than 59% when treatments were applied without mowing soft rush. Mowing had no impact on soft-rush control with herbicides 12 MAT. Applications of 2.24 kg/ha 2,4-D provided at least 90% control 12 MAT, but this was not significantly different from the premix of 2,4-D dicamba or 2.24 0.02 kg/ha 2,4-D carfentrazone treatments. Therefore, effective control of soft rush can be obtained with the use of 2,4-D amine or products that contain 2,4-D amine.
Nomenclature: 2,4-D amine; fluroxypyr; triclopyr; carfentrazone; dicamba; aminopyralid; soft rush, Juncus effusus L. IUNEF; limpograss, Hemarthria altissima (Poir.) Stapf & C.E. Hubb.