Cogongrass (Imperata cylindrica) is an invasive weed that can choke out even the most hardy native plants. The Asian native grass is a federally regulated noxious invasive weed, and is considered one of the worst weeds in the world. Cogongrass can easily displace native plants that are used by birds, animals and insects for forage and shelter. The weed also poses a threat as a fire hazard. Cogongrass burns very hot and will burn beneficial plants commonly managed with fire. When cogongrass is detected in South Carolina, the Department of Plant Industry assists property owners in determining appropriate eradication methods. DPI monitors all known cogongrass sites to prevent further spread.

Cogongrass grows from a crown and is not a branching grass. It can grow as tall as five feet. You can tell cogongrass apart from other weeds in one of three ways:

cogongrass flowers

Flowers are usually a light maroon color before they open during late April-May, although mowing or chemical treatment may prompt the plant to flower at other times.

cogongrass leaf and ruler

Leaves are about 0.5-1.0 inches wide and usually have a conspicuous, offset midrib sometimes white on older plants.

cogongrass rhizomehd

Rhizomes are sharply pointed, segmented, and hard underground stem at its base from which its roots emerge in dense mats. While the sharp rhizome is a great diagnostic characteristic, please DO NOT dig up any suspect grass. One segment of a rhizome can start a new plant.

If you suspect you have found Cogongrass please report it using the Cogongrass Reporting Tool.

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