Nutsedge is difficult to control - when it's pulled by hand, it usually just germinates more nutsedge. Halo 5WDG Select is a selective herbicide for post-emergence control of sedges such as purple and yellow nutsedge, Kyllinga species and certain broadleaf weeds. Halo can be applied to turfgrass, landscape ornamental beds, and on other non-crop sites where weeds are an issue and actively growing. For use on established cool and warm season grass types. 13.5 grams.