Cogongrass in Georgia

Cogongrass, Imperata cylindrica (L.), is considered the seventh worst weed in the world and listed as a federal noxious weed by USDA Animal and Plant Health Inspection Service - Plant Protection and Quarantine. Cogongrass was first introduced into the United States near Grand Bay, Alabama in 1911 via seed packing material in shipping containers from Japan.

Since its introduction, it has become widespread throughout Alabama, Mississippi, and Florida and is moving into Georgia and South Carolina. This grass suppresses and eliminates natural vegetation thereby significantly reducing tree & plant regeneration, wildlife habitat, forage, and ecological diversity.

Cogongrass infestations are being found primarily in south Georgia but is capable of growing throughout the state. It grows in numerous soil types with the exception of saturated soils and is highly adaptable from full sunlight to shade. Cogongrass invades forests, pastures, old fields, roadsides, utility rights-of-ways, and ditches. The grass spreads through both rhizomes and seed production. Forming dense mats, it is extremely flammable creating hazardous prescribed burning and wildfire conditions. Cogongrass is difficult to eradicate once it has become established due to the tremendous root system that must be completely eliminated.

The first step in eradicating cogongrass is educating individuals how to identify the grass. The most recognizable feature of cogongrass is the fluffy white seed heads that are produced in the spring (March-June) immediately following grass "green-up." When not in the flowering stage, inspection of the roots is the most identifiable feature. Cogongrass has sharp pointed, scaly rhizomes with a very dense root system. It will usually grow in a circular-shaped pattern. Although not a sole identification feature, the grass also has an off-centered midrib on long leaf blades (1-5 feet).

The Georgia Forestry Commission (GFC) is taking a proactive approach at eradicating cogongrass in Georgia, and formed the Cogongrass Task Force in 2004. A diverse group of government and private agencies and groups have joined forces within this Task Force into a collective effort to detect and eradicate this plant form our State. Anyone suspecting they have seen cogongrass should contact their local Georgia Forestry Commission office. A GFC representative will inspect the site. If confirmed to be cogongrass, a chemical eradication program will be initiated at no expense to the landowner. In the meantime, avoid mowing or disking through or near a known or suspected cogongrass spot since this could move seed or root fragments to other areas.

Join the cogongrass eradication team in Georgia and be a part of protecting our state's forest and wildlife habitat. Report a potential cogongrass sighting online or call your local GFC Forester.

Cogongrass is the only warm season grass that produces cotton-like seeds in the spring.

Cogongrass seeds dispersing
Cogongrass seeds dispersing - Photo by Bill Lamp, Georgia Forestry Commission
Cogongrass flowering
Cogongrass flowering - Photo by Bill Lamp, Georgia Forestry Commission


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