itchgrass
(Rottboellia cochinchinensis (Lour.) W.D. Clayton)

Overview

Appearance

Rottboellia cochinchinensis is an annual grass that invades disturbed and agricultural areas throughout the southeastern United States.

Foliage

Stems and leaves are covered with stiff, irritating hairs. Stems can reach a height of 1-10 ft. (0.3-3 m). Leaf blades are 5.9-17.7 in. (15-45 cm) long, 0.2-0.8 in. (5-20 mm) wide and flat.

Flowers

The inflorescence is a jointed, cylindrical raceme, 1-6 in. (2.5-15.24) long.

Fruit

Under favorable conditions, Rottboellia cochinchinensis starts producing seeds 6-7 weeks after emergence. Seed production continues throughout the growing season.

Ecological Threat

Rottboellia cochinchinensis invades agricultural fields and other disturbed areas. The hairs on the stems and leaves can cause severe irritation, and the plant is unpalatable to livestock and wildlife. It is native to the Old World tropics, but it is currently widespread throughout the world’s tropical regions and in the southeastern United States.

Resources

• Domestic Programs Pest Evaluation - USDA APHIS PPQ
• Noxious weeds of the Federal Noxious Weed Act - USDA APHIS PPQ
• Federal Noxious Weed Disseminules of the U.S. - USDA-APHIS

Selected Images

Maps

Invasive Listing Sources

• Federal Noxious Weeds
• Florida Noxious Weeds
• Georgia Exotic Pest Plant Council - Category 3
• Maryland Invasive Species Council - Invasive Species of Concern in Maryland
• Massachusetts Noxious Weeds
• Massachusetts Prohibited Plant List
• Mississippi Noxious Weeds
• Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
• South Carolina Exotic Pest Plant Council
• South Carolina Plant Pest List
• Tennessee Exotic Pest Plant Council
• Texas Noxious Weeds
• USDA APHIS Regulated Pest List
• WeedUS - Database of Plants Invading Natural Areas in the United States

References