Weeds are a common problem in lawns and gardens. One commonly encountered weed, especially in wet years, is yellow nutsedge.
Yellow nutsedge (Cyperus esculentus) is a warm-season perennial. It is not a grass nor a broadleaf weed, but a sedge. The grass-like leaves are light green to yellowish green in color and shiny in appearance. Yellow nutsedge is an erect plant. The stem near ground level is triangular. The leaves come off the stem in sets of threes. Yellow nutsedge reproduces primarily by small underground tubers called nutlets. Plants also produce seeds. Flowers are yellowish or yellowish brown and are borne on small spikelets. Yellow nutsedge grows most rapidly during the warm summer months. It is often found in wet or poorly drained soils.
Control of yellow nutsedge in gardens and lawns is difficult. Patience and persistence will be required.
The best way for home gardeners to control small infestations of yellow nutsedge in gardens is by hand digging. Carefully dig up plants with a small trowel or weeder. (If the plants are pulled, some of the nutlets will break off in the soil and sprout in a few weeks.) When digging yellow nutsedge, the objective is to remove the entire plant, including roots and nutlets.
In lawns, yellow nutsedge can be controlled with herbicides. Multiple applications will be necessary. Begin applying herbicides in late spring/early summer. Products with active ingredients of sulfentrazone (Ortho Nutsedge Killer for Lawns), sulfentrazone plus prodiamine (Bonide Sedge Ender), and halosulfuron (SedgeHammer, Nutgrass Killer II Selective Herbicide, and Hi-Yield Nutsedge Control) provide the best control. The best way to prevent a yellow nutsedge infestation in the lawn is to maintain a healthy, dense stand of turfgrass by following proper cultural practices.
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