Native Range

Western Asia and Indo-Pakistan region

Appearance

Giant reed is a perennial grass typically growing 6½–26 ft (2–8 m) tall from a rhizomatous root system. Stems are round, S–1½ in (1–4 cm) in diameter, and hollow between nodes. Leaves are alternate and very distinctly two-ranked, growing in a single plane. Leaves are a pale blue-green, typically 1–2 ft (30–60 cm) long, and taper to a fine tip. The leaves clasp the stem and have fine tufts of hair at the base. Flowers are borne in large feathery plumes 1–2 ft (30–60 cm) long. Seeds are often absent or are sterile.

Impact

Giant reed forms massive stands in riparian areas, displacing native plants and animals (both terrestrial and aquatic), consuming scarce water resources, and increasing wildfire threats. Large infestations alter channel morphology, increase erosion, facilitate the spread of cattle fever ticks, and impede law enforcement activities on the international border of Mexico and the USA.

Reference

Moran, P.J. and J.A. Goolsby. 2022. Giant Reed (Arundo donax): History and Ecology in North America. In: R.L. Winston, Ed. Biological Control of Weeds in North America. North American Invasive Species Management Association, Milwaukee, WI. NAISMA-BCW-2022-37- GIANT REED-P. https://bugwoodcloud.org/resource/files/23208.pdf

Resources

• A Field Guide for the Identification of Invasive Plants in Southern Forests - USDA Forest Service
• Plant Invaders of Mid-Atlantic Natural Areas - National Park Service and U.S. Fish and Wildlife Service
• Weeds Gone Wild: Alien Plant Invaders of Natural Areas - Plant Conservation Alliance
• Element Stewardship Abstract - The Nature Conservancy
• Fire Effects Information System - USDA Forest Service
• Weed of the Week - USDA Forest Service
• Weed Field Guide - USDA Forest Service

Selected Images

Maps

Invasive Listing Sources

• Alabama Invasive Plant Council
• Apalachicola Invasive Working Group - High
• Arizona Noxious Weeds
• California Invasive Plant Council
• California Noxious Weeds
• Colorado Noxious Weeds
• Georgia Exotic Pest Plant Council - Category 3
• Idaho Invasive Species Act
• Indiana Invasive Species Council - Invasive Plant List
• Invasive Plant Species of West Virginia
• Invasive Species of Concern in Georgia
• Jil M. Swearingen, Survey of invasive plants occurring on National Park Service lands, 2000-2007
• John Randall, The Nature Conservancy, Survey of TNC Preserves, 1995.
• Kentucky Exotic Pest Plant Council - Watch List
• Maryland Cooperative Extension Service.  2003. Invasive Plant Control in Maryland. Home and Garden Information Center, Home and Garden Mimeo HG88. 4 pp.
• National Park Service, Mid-Atlantic Exotic Plant Management Team Invasive Plant List
• National Park Service, National Capital Region Exotic Plant Management Team Invasive Plant List
• Nevada Noxious Weeds
• New Invaders of the Northwest
• New Mexico Noxious Weeds
• Non-Native Invasive Plants of Arlington County, Virginia
• Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
• Ontario’s Invading Species Awareness Program Tracked Species List
• Pennsylvania Department of Conservation and Natural Resources Invasive Plants
• South Carolina Exotic Pest Plant Council
• Tennessee Exotic Pest Plant Council
• Texas Noxious Weeds
• Utah Noxious Weeds - Early Detection
• WeedUS - Database of Plants Invading Natural Areas in the United States
• West Virginia Native Plant Society, Flora West Virginia Project, and West Virginia Curatorial Database System, September 3, 1999
• Wisconsin Noxious Weeds
• Wisconsin's Invasive species rule – NR 40

References