Ohio Perennial and Biennial Weed Guide

Family:

Grass Family (Poaceae)

Other Names:

Phragmites communis, Phragmites maximus, cane grass, common reedgrass, giant reed, quilrod, reed grass.

Origin and Distribution:

Common reed is a native, emergent aquatic grass found in temperate regions around the world. It occurs throughout most of the U.S. and southern Canada, and more locally, in central and northeastern Ohio. This plant grows in wet, moderately fertile soils, such as along the banks of lakes, ponds, streams, marshes, ditches and roads, and in wet fields. Farm and road machinery help to distribute its rhizomes across the landscape, and once established, common reed will spread quickly over an area. Common reed is tolerant of stagnant and gently flowing water, and of both brackish (slightly saline) and alkaline conditions. However, it is not tolerant of high salinity or drought.

Plant Description:

Common reed is a large, bamboo-like, sod-forming perennial grass that reproduces primarily by rhizomes (horizontal underground stems), sometimes by stolons (horizontal stems at the surface of the ground that root at the nodes), and rarely by seeds. This plant grows to impressive heights of 20 feet, with stout, cane-like stems and large, purple, feathery clusters of flowers. Common reed often forms dense patches.

• Root System:

  Common reed has long, stout, scaly, creeping rhizomes (horizontal underground stems) that form extensive mats. Rhizomes typically grow 1 to 3 feet below the soil surface, but can reach depths greater than 6 feet. Roots are produced at the joints (nodes) of the rhizomes.

• Stems:

  The stiff, smooth, erect stems are hollow, round, and unbranched. Stems can grow 1/5 to 3/5 inch wide and 2 to 14 feet tall, sometimes reaching heights of 20 feet. The stems can be almost woody, and are sometimes purplish. Roots grow from the base of flooded stems.

• Leaves:

  Leaves are rolled in the bud. The leaf blade (free part of the leaf) (2 to 24 inches long, 1/2 to 1 1/2 inches wide) is broad, stiff and flat, with rough margins. The leaf surface is hairless and ridge-veined above, and hairless or sparsely hairy below. Leaf blades taper to a long point and narrow slightly toward the stem. The leaf sheath (the part of the leaf surrounding the stem) is smooth, except for fine hairs along the margins. The sheath margins usually overlap and are often purple. The ligule (projection inside on the top of the sheath) is composed of a short membrane crowned with a ring of short, dense, white hairs and long, silky hairs; however, the long hairs fall off as leaves mature. Auricles (appendages at the top of the sheath) are absent.

• Flowers:

  The feathery, plume-like flower head is 5 to 16 inches long and composed of many long branches that point upwards. Narrow clusters of flowers are arranged densely along the branches. The flowers are surrounded by silky white hairs, and are purplish at first, becoming tawny to dark brown at maturity.

• Fruits and Seeds:

  Seeds are brown, thin and delicate. A long, narrow bristle is attached to each seed. The seed and bristle together measure approximately 1/3 inch long.

Similar Species:

Common reed may be confused with johnsongrass (Sorghum halepense) and reed canarygrass (Phalaris arundinacea). All 3 are large perennials with creeping rhizomes, but common reed grows taller than both. In addition, it has a feathery, dense flower head and thin seeds, compared to the nonfeathery flower head and plump, oval seeds of johnsongrass. Common reed has a hairy ligule, while the ligule of reed canarygrass is completely membranous.

Biology:

Flowering occurs from July to September, which is later than for most other grasses. Common reed spreads primarily by rhizomes, and new plants can easily establish from rhizome fragments. Once established, this plant can form large, dense, monospecific colonies. Common reed can encroach into standing water up to 6 feet deep

Common reed is usually a problem in or near fresh or brackish water, but it can also be troublesome on sandy to loamy soils with damp subsoils. Large clumps of grass can block flow in irrigation channels and flood mitigation systems. However, common reed does provide some benefit to the ecosystems that it inhabits. Fish and water birds find shelter and breeding sites in the dense reed stands, and the interwoven networks of rhizomes and roots help to prevent erosion along lakeshores and river banks.

Toxicity:

None known.

Facts and Folklore:

• The genus name, Phragmites, is derived from the Greek word for 'fence', and refers to common reed's fence-like growth along the banks of streams and ponds.

• Redwing blackbirds preferentially nest in common reed stands.

• Common reed was used in earlier times to make pen points (quills). Today, the dried stems are used in the Southwest and Mexico for thatching, mats, cordage and arrows. This species is grown for paper production in Russia.