Cogongrass (Imperata cylindrica) is an invasive weed originating from Southeast Asia that can be found lining roadways in Alabama, Mississippi and Florida. Now known as one of the world’s worst weeds, cogongrass was initially introduced into Mississippi and Florida as potential forage for wildlife species and as a soil stabilizer. However, cogongrass chokes out native plant life and poses a fire hazard during the dry season. Cogongrass was first spotted in South Carolina in 1987 in Hampton County.
Cogongrass spreads through the use of rhizomes, which are underground stems from which roots emerge. The rhizomes of this grass are sharp, segmented and hard, and one piece of rhizome will readily form a new plant. For this reason, please do NOT attempt to dig up suspect cogongrass. The grass flowers during late April and through May. The flowers of cogongrass are white and fluffy, making the weed easily recognizable. The leaves of cogongrass are finely serrated, which reduce its value as a wildlife foraging source. The midrib of a cogongrass leaf is conspicuous and offset from the center of the blade, a characteristic that also helps in cogongrass identification.
The dense mats of cogongrass displace valuable native plant species and create a fire hazard during prescribed burns, when it burns fast and hot. This weed increases the frequency and intensity of fires, and if left to grow on its own can fundamentally alter an ecosystem. Once cogongrass is established, the weed is extremely difficult to eliminate. Cogongrass inhabits right-of-ways, forests, agricultural fields, and residential, commercial and industrial areas.
There are several active sites in South Carolina that are being eradicated by the Cogongrass Task Force. If you suspect you have found cogongrass, please contact Clemson University Department of Plant Industry (firstname.lastname@example.org) or submit your observation to the Cogongrass Survey Program.