common reed
(Phragmites australis (Cavanilles) Trinius ex Steudel)

Overview

Appearance

Phragmites australis is a tall, perennial grass that can grow to heights of 15 ft. (4.6 m) or more. Broad, pointed leaves arise from thick, vertical stalks.

Foliage

Leaves are 6-23.6 in. (15-60 cm) long, 0.4-2.4 in. (1-6 cm) wide, flat and glabrous.

Flowers

The flower heads are dense, fluffy, gray or purple in color and 5.9-15.7 in. (15-40 cm) long. Flowering occurs from July to October.

Fruit

The seeds are brown, light weight, and about 0.3 in. (8 mm) long. In the fall the plant turns brown, and the inflorescences persist throughout the winter.

Ecological Threat

Phragmites australis is usually found in dense thickets growing in or near shallow water. These thickets displace native wetlands plants, alter hydrology and block sunlight to the aquatic community. It is native to Eurasia and Africa. Native Phragmites do occur in the United States and they are sometimes very difficult to distinguish from the exotics.

Resources

• Phragmites Field Guide: Distinguishing Native and Exotic Forms of Common Reed in the U.S. - Plant Conservation Alliance
• A Guide to the Control and Management of Invasive Phragmites - Michigan Department of Natural Resources
• Biological Control of Invasive Plants in the Eastern United States - USDA Forest Service
• Weeds Gone Wild: Alien Plant Invaders of Natural Areas - Plant Conservation Alliance
• Element Stewardship Abstract - The Nature Conservancy
• Morphological differences between native and introduced genotypes - Cornell University
• Weed of the Week - USDA Forest Service
• Plant Invaders of Mid-Atlantic Natural Areas - National Park Service and U.S. Fish and Wildlife Service
• Best Management Practices - Ontarios Invading Species Awareness Program
• Fact Sheet - Ontarios Invading Species Awareness Program

Selected Images

Maps

Invasive Listing Sources

• Alabama Invasive Plant Council
• Alabama Noxious Weeds - Class C Noxious Weed
• Alberta Fisheries Act
• Apalachicola Invasive Working Group
• City of Ann Arbor Michigan Parks and Recreation
• Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, 1994.
• Connecticut Invasive Plant List
• Connecticut Invasive Plant Working Group
• Connecticut Noxious Weeds
• Delaware Invasive Species Council
• Delaware Invasive Species Council Invasive Species List
• Georgia Exotic Pest Plant Council - Category 3
• Hoffman, R. & K. Kearns, Eds. 1997. Wisconsin manual of control recommendations for ecologically invasive plants. Wisconsin Dept. Natural Resources, Bureau of Endangered Resources. Madison, Wisconsin. 102pp.
• Idaho Noxious Weeds
• Indiana Invasive Species Council - Invasive Plant List
• Invasive Plant Association of Wisconsin
• 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
• Kentucky Exotic Pest Plant Council - Severe Threat
• Maine Invasive Plants
• Maryland Aquatic Nuisance Species Plan
• Maryland Cooperative Extension Service.  2003. Invasive Plant Control in Maryland. Home and Garden Information Center, Home and Garden Mimeo HG88. 4 pp.
• Maryland Department of Natural Resources Policy: Restriction on Planting Exotic Invasive Plants
• Maryland Invasive Species Council - Invasive Species of Concern in Maryland
• Massachusetts Noxious Weeds
• Massachusetts Prohibited Plant List
• Michigan’s Prohibited and Restricted Species
• Mid-Atlantic Field Guide to Aquatic Invasive Species
• Missouri SRISP Species List
• New Hampshire Invasive Species Committee. 2005. Guide to Invasive Upland Plant Species in New Hampshire. New Hampshire Department of Agriculture,  Markets and Food Plant Industry Division and New Hampshire Invasive Species Committee.
• New Hampshire Prohibited Aquatic Species
• New Jersey Invasive Species Strike Team 2017 Invasive Species List
• New York Regulated and Prohibited Invasive Species - Prohibited
• Non-Native Invasive Plants of Arlington County, Virginia
• Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
• Pacific Northwest Exotic Pest Plant Council, 1998
• Pennsylvania's Field Guide to Aquatic Invasive Species
• Plant Invaders of Mid-Atlantic Natural Areas
• Rhode Island Natural History Survey
• South Carolina Exotic Pest Plant Council
• South Carolina Illegal Aquatic Plants
• South Carolina Plant Pest List
• Tennessee Exotic Pest Plant Council
• Utah Noxious Weeds - Contain
• Virginia Invasive Species Management Plan 2012
• Washington Noxious Weeds
• WeedUS - Database of Plants Invading Natural Areas in the United States
• West Virginia Invasive Species Strategic Plan and Volunteer Guidelines 2014
• West Virginia Native Plant Society, Flora West Virginia Project, and West Virginia Curatorial Database System, September 3, 1999

References