Reed canary grass (Phalaris arundinacea) is native to Europe, Asia, and North America. The European variety is particularly aggressive and it is likely that the invasive varieties are cultivars that were crossbred for fast growth. Reed canary grass is a cool-season perennial that typically invades wetlands and floodplains but it can also grow in dry soils in shaded wooded areas. It is a sod-forming grass that spreads through rhizomes (underground horizontal stems) and runners. Once it has invaded an area it can completely eliminate other vegetation because of its dense growth. It can even inhibit tree growth in floodplain forests.
Habitat: typically areas with wet soils including primarily wetlands and floodplains adjacent to rivers and streams
Height: 2-9 feet
Site Requirements
Leaves: flat, gradually tapering, hairless blade is rough on both sides, 1-4 feet long and up to 0.75 inches wide; long membranous ligule
Flowering Dates: May-July
The branching flower clusters (panicles) of reed canary grass are 3-6 inches long. Flowers are initially greenish purple and change to yellowish brown as seeds mature.
Control Methods
Reed canary grass is difficult to control so a combination of methods is necessary. Control practices need to suppress above ground growth, address below ground rhizomes and seed bank, and promote native species to compete with reed canary grass. The timing of treatment is important and persistence is key. Generally control methods will need to be applied for at least 3-5 years in a row. Reed canary grass rebounds quickly if a single year is skipped. In Iowa, cattle grazing, disking, mowing, and chemical control have been effective to varying degrees. Our chemical control of unwanted vegetation article has information on specific herbicides to use. For more detailed information on timing and methods of control check out this reed canary grass management guide.
stages of reed canary grass flower clusters - Photo by Leslie J Mehrhoff, University of Connecticut, Bugwood.org
