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cogongrass

Imperata cylindrica (L.) Beauv.

USDA PLANTS Symbol: IMCY
U.S. Nativity: Exotic
Habit: Herb


Synonym(s): cogon grass, alang-alang, Japanese blood grass

Appearance
Imperata cylindrica is a perennial, colony-forming grass which can grow up to 6 ft. (1.8 m) tall.
Foliage
Leaves have an off-center, whitish midrib and finely serrated margins. Leaves are up to 6 ft. (1.8 m) long, 0.5-0.75 in. (1.3-1.9 cm) wide, stiff, and have a sharp, pointed apex. Rhizomes are whitish, branched, scaly and sharp at the tips.
Flowers
Flower heads are 2-8 in. (5.1-20.3 cm) long, silvery-white and cylindrical.
Fruit
Imperata cylindrica is best identified in the spring by the large fuzzy panicle of flowers and seeds, giving the plant a cottony or silky look.
Ecological Threat
Imperata cylindrica is an extremely aggressive invader with the capability of invading a range of sites. It forms dense, usually circular infestations that exclude all other vegetation. It is native to Southeast Asia and was accidently introduced into the southeast United States in packing material in the early 1900s. It was also intentionally introduced for erosion control and livestock forage.


Identification, Biology, Control and Management Resources

Invasive Species Management Plans for Florida - University of Florida - Center for Aquatic and Invasive Plants
Nonnative Invasive Plants of Southern Forests - USDA Forest Service
Biological Control of Invasive Plants in the Eastern United States - USDA Forest Service
Domestic Programs Pest Evaluation - USDA APHIS PPQ
Cogongrass Web Site - Bugwood Network
Identifying and Controlling Cogongrass in Georgia - GA Invasive Species Task Force
Weeds Gone Wild: Alien Plant Invaders of Natural Areas - Plant Conservation Alliance
Federal Noxious Weed Disseminules of the U.S. - USDA-APHIS
Weed of the Week - USDA Forest Service
Identification and Biology of Non-Native Plants in Florida's Natural Areas - University of Florida