giant reed
(Arundo donax L.)

Overview

Appearance

Arundo donax is a perennial grass that can reach up to 20 ft. (6.1 m) in height. Although it can be much shorter when damaged or stressed. The stem resembles a corn stalk.

Foliage

Leaves are long, flat and grow up to 1.5 ft. (0.5 m) long. They can be green or have variegated green and white stripes the length of the blade.

Flowers

Flowering occurs in late summer to early fall, when plants are most easily recognized because of the large, dense flower plumes that develop at the tops of the culms. The plums can grow up to 3 ft. (0.9 m) in length.

Fruit

No fruits or seeds typically outside of its native range. The plant spreads through rhizomes and stem nodes that come in contact with the soil.

Ecological Threat

Arundo donax invades wetlands such as ditches, stream banks and lake shores. Arundo donax competes for water, nutrients and radiation, suppresses and excludes native vegetation which degrades wildlife habitat, increases fire risks and interferes with flood control. Arundo donax is native to India and was introduced into the United States in the early 1800s for ornamental purposes.

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