Photo credit: A.S. Kers/Flickr

Reed Canary Grass

(Phalaris arundinacea)

Report this Species!

If you believe you have found this species anywhere in Pennsylvania, please report your findings to iMapInvasives by submitting an observation record.

Species at a Glance

Reed canary grass is a large cool-season perennial that grows 0.6-2.7 m (2-9 ft) in height and forms large monotypic stands that can dominate an area. Two virtually indistinguishable ecotypes are thought to exist in the United States, including a native ecotype and a more aggressive Eurasian one.

Identification

Leaves: Long, gradually tapering leaves have flat blades and a rough texture on both the upper and lower surfaces. Size ranges from 9-25 cm (3.5-9.8 in) long and 0.5-2 cm (0.2-0.8 in) wide. Coloration can be light green to a straw color. A transparent, thin, membranous outgrowth called a ligule is also present at the junction of the leaf and stalk.

 

Flowers: Densely packed clusters called panicles are generally 7.5-15 cm (3-5.9 in) in length and arise from the stem high above the leaves from May to mid-June. At first, they appear a green to purple color but gradually change to beige over time.

 

Stems/Roots: Sturdy, often hollow, hairless stems are 1 cm (0.4 in) in diameter and have some reddish coloration near the top.

Similar Species

The highly transparent ligule is helpful in distinguishing reed canary grass from the non-native orchard grass (Dactylis glomerata), which has leaves with wider blades, and more narrow and pointed clusters of flowers. Additionally, bluejoint grass (Calamagrostis canadensis) may be mistaken for reed canary grass in areas where orchard grass is rare.

Habitat

A wetland plant, this species typically occurs in soils that are saturated for most of the growing season but where standing water does not persist for extended periods. Ideal conditions typically occur in roadside ditches, rights-of-ways, river dikes, levees, shallow marshes, and meadows.

Spread

Seeds and creeping rhizomes help reed canary grass spread aggressively. Seeds can be moved from one wetland to another by waterways, animals, humans, or machines.

Distribution

Reed canary grass is native to temperate regions of Europe, Asia, and North America. Historically, the Eurasian ecotype was planted throughout the United States for forage and erosion control. It has become naturalized in much of the northern half of the United States and is widespread throughout the Mid-Atlantic region.

 

Note: Distribution data for this species may have changed since the publication of the Mid-Atlantic Field Guide to Aquatic Invasive Species (2016), the source of information for this description.

Environmental Impacts

Reed canary grass forms large monotypic stands that harbor few other plant species and are of little use to wildlife. Once established, it dominates an area by building up a seed bank that can eventually erupt, germinate, and recolonize treated sites.

Video
Note

Information for this species profile comes from the Mid-Atlantic Field Guide to Aquatic Invasive Species (2016).

The Pennsylvania iMapInvasives Program is a partnership of the Western Pennsylvania Conservancy, the Pennsylvania Natural Heritage Program, and NatureServe.

Funding for Pennsylvania iMapInvasives is provided by the Great Lakes Restoration Initiative.

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Pennsylvania Natural Heritage Program, iMapInvasives partner
Great Lakes Restoration Initiative logo, iMapInvasives funding source