Invasive Plant of the Month: September 2012
Phragmites (Phragmites australis)
Also Known As
Common reed, Danube grass
Phragmites is a perennial grass that is native to Asia and Africa. It can form dense stands that include both new growth and dead stems from previous years. Similar in appearance to giant reed (Arundo donax), phragmites can be distinguished by its leaf bases, which are attached by narrow sheaths and do not clasp the stem. Several native phragmites species exist in the United States and are often extremely difficult to distinguish from the exotic species. Phragmites reproduces by seed and by creeping rhizomes.
Phragmites produces thick, hollow cane-like stems that are approximately 1 inch in diameter and can reach up to 20 feet tall. In the autumn, the plant turns tan, the leaves drop off, and only the fluffy plume remains.
Long, narrow leaves have smooth margins and gradually taper toward the tip. Leaves are 6–24 inches long and 0.5–2 inches wide at the base.
Flowers occur in large, feathery flower heads that are 6–20 inches long and golden or purple in color. Flowering occurs from July to October.
Seeds and Fruit
Tiny seeds are about 0.05 inches long.
Phragmites is typically found in or near wetland areas, and along roadsides, riverbanks, lakeshores, and ditches. It can grow in water up to 6 feet deep and can tolerate mostly dry areas.
Species Identification and CharacteristicsBugwoodWiki
Distinguishing Native and Exotic Forms of Common Reed in the US: Plant Conservation Alliance (PDF)
Invasive.org Images and Overview
Invasive Phragmites: What Is It and What Can We Do? (VIDEO)
Plant Conservation Alliance Fact Sheet
USDA Forest Service Fact Sheet (PDF)
Management and Control Resources