Yellow nutsedge may not be the worst weed problem in athletic fields, but when conditions are right, it can certainly be a nuisance. Fortunately, nutsedge is relatively easy to control when using the proper herbicide at the correct stage of growth. Yellow nutsedge is a perennial weed with coarse, shiny foliage and three-sided stems. It spreads via extensive rhizomes and tubers (often called nutlets), and is often found in poorly-drained areas and in newly established turf. The most effective control of nutsedge with herbicides is obtained when foliage is visible in the turf canopy (3-8 leaf stage), and before tubers mature in early July. It’s important to treat nutsedge before tubers form because these underground structures can give rise to many new plants in subsequent years.
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