Purple and yellow nutsedge are common weeds found throughout the sugarcane industry. Their triangular shaped stem easily distinguishes them from grass and broadleaf weeds. Purple nutsedge is very competitive during sugarcane establishment, particularly after planting and in early spring. Previous research has shown that purple nutsedge can reduce sugarcane tillering and stalk weight if not managed. The fallow period is an opportune time to manage purple and yellow nutsedge. Both species reproduce from tubers, and tillage is not an effective means of control. Glyphosate is effective in managing many problematic weeds during the fallow period; however, when applied alone, does not provide acceptable control of nutsedge.

Halosulfuron, the active ingredient found in the herbicides Permit, Halomax, Herbivore, and Yukon (halosulfuron and dicamba) can be mixed with glyphosate to enhance purple and yellow nutsedge control. The herbicides Envoke (trifloxysulfuron) or Classic (chlorimuron) can also be mixed with glyphosate to enhance yellow nutsedge control and provide residual control of broadleaf weeds. Recently, the 24(c) Special Local Need Label for Classic was renewed and expires on January 31, 2029.

Since the previously mentioned products control nutsedge slowly, they should be applied with the June glyphosate application. Classic herbicide should be applied at least 60 days prior to the planting of sugarcane. For additional information, please refer to the Louisiana Suggested Chemical Weed Control Guide or the herbicide label.