Green kyllinga

About

A low, mat-forming perennial sedge that thrives in wet, closely mowed lawns. It has been spreading quickly through southern lawns and is very hard to control once mats form.

Also called kyllinga, shortleaf spikesedge

How to identify it

Look for

Fine, glossy, dark green leaves (one to three per stem) with tiny barbs on the edges and triangular stems. The flower head is a small, round, green ball at the top of the stem. Reddish underground runners knit into dense mats, and there are no tubers.

Look-alikes

Yellow and purple nutsedge are taller, form tubers, and have spiky, branched flower clusters instead of one round head.

Where it grows

Moist to wet lawns in full sun, low spots, poorly drained areas and irrigated beds.

When

Grows from late spring until frost and flowers from about May through October; it stays green in mild winters but turns brown in colder areas.

How it spreads

Spreads by seed and by underground runners, and any runner piece with a joint can start a new plant.

Most common in

What to do, gentlest first

Start at the top. Weed killers are a last step; always read and follow the label.

1. Dry out wet spots and mow a bit higher Prevent

   Fix poor drainage and cut back irrigation where it keeps soil wet. Kyllinga thrives when lawns are mowed an inch or lower.

2. Dig out small mats completely By hand

   Dig small patches while soil is moist, taking every runner. Leftover pieces regrow.

3. Halosulfuron, sulfentrazone or imazaquin Conventional spray

   In lawns, spray halosulfuron or sulfentrazone, or imazaquin in warm-season grass, on actively growing plants, and plan on repeat applications.

   Read and follow the label. Many lawn herbicides kill garden plants, so keep spray and drift off beds and vegetables.

Uses, wildlife and pets

Pets

Not listed as toxic to dogs, cats or horses by the ASPCA.