Nutsedge: What You Need to Know

Biology:

Nutsedge is a very aggressive and persistent weed that commonly infest lawns, gardens, or any home landscapes during the warmer months. At times, it can be difficult to eradicate and control. Successful management of nutsedge involves both cultural and chemical management.

Identification:

Nutsedge, often called “nutgrass”, closely resembles grass, and can be distinguished by their triangular or V-shaped stems. Most nutsedges are perennial, survive in the soil, sprout in the spring and will die back in the fall when temperatures decrease. The tubers (often called “nutlets”) and rhizomes (underground stems) can grow eight to fourteen inches below the soil surface. New tubers can form patches 10 feet or more in diameter due to the spread of small tubers, by creeping rhizomes, or by seed.

Cultural Control:

Nutsedge thrives in moist areas, and its’ presence could indicate the irrigation is too frequent, possibility of poor drainage, or sprinklers are leaky. Since excessive moist soil will encourage growth, proper irrigation rate and timing are especially important. It is best, for many reasons, to water lawns deeply but infrequently, to allow the surface soil to become dry between water applications.

Chemical Control:

Nutsedge can be controlled chemically with postemergence herbicides. Herbicides should be applied when nutsedge is actively growing and in warm conditions. However, herbicides cannot be applied during hot or dry weather (> 90 F) to minimize the chances for injury to the turfgrass. This presents a big challenge for our technicians when treating for nutsedge since they may be on your property to fertilize but unable to treat the nutsedge due to the temperature at the time of treatment.

Images:

Yellow Nutsedge can be identified by the tall lime green shoots that usually protrude 2-3 inches above your normal healthy grass blades.