WEED ID · PERENNIAL GRASS

King Ranch bluestem

Also called KR bluestem, Old World bluestem

A weedy perennial grass common along Texas roadsides and utility areas. It can start as a bunch, then spread out in mowed turf.

When you’ll see it: Summer through fall

Upright King Ranch bluestem seed stalk with thin, pale fingers fanning out from the top, growing in tall grass beside a parked car — Photo: Tyler Cannon, CC BY 4.0

How to spot it

Starts as a bunch of thin stems that are light green and turn straw colored when mature
Stems can reach about 4 feet tall if left unmowed
Loose seedhead with 3 to 8 branches, silvery to purplish
Seedheads start showing in early summer
In mowed turf, it can spread out by runners instead of staying in a bunch

Why it shows up

King Ranch bluestem spreads mostly by seed. It takes hold fast on bare soil, and it is common along roadsides. In mowed turf it can also spread by rhizomes and runners.

How we treat it

King Ranch bluestem is very hard to control. A pre-emergent will not stop a plant that is already up. We will look at it on a visit and tell you what is realistic, which may mean spot treating with a product labeled for your grass type and coming back. We also fertilize to keep the lawn thick, since this grass moves in fast on bare soil.

What you can do

Dig out small plants early, before they make seed.
Fill in bare spots. This grass takes hold fast on bare soil.
Check lots and roadsides next to your yard, where seed comes from.

WANT IT HANDLED?

Let a licensed applicator take it from here.

Tell us about your lawn. We’ll get back to you with a free quote.

Prefer to talk? 817-382-1722

Licensed applicator, Texas Department of Agriculture · License #0984138