reed mannagrass

Cyperales > Poaceae > Glyceria maxima (Hartman) Holmb.

Reed mannagrass is a perennial, semi-aquatic, rhizomatous grass. Stems are unbranched and can reach 2-8.2 ft. (0.6-2.5 m) in height. Leaves are 12-23.6 in. (30-60 cm) long, 0.2-0.8 in. (6-20 mm) wide, with an acute apex and a prominent midrib. Flowering occurs in June-August, when flowers appear in 6-12 in. (15-30 cm) long panicles. This plant reproduces primarily vegetatively and occurs in sunny to semi-shady wetlands, where it can form dense impenetrable stands. Reed mannagrass is native to northern Eurasia and was first found in North America in 1940 on the edge of Lake Ontario.

Identification, Biology, Control and Management Resources

  • Weeds of the Week - USDA Forest Service, Northeastern Area, Forest Health Protection

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Leslie J. Mehrhoff, University of Connecticut,

Leslie J. Mehrhoff, University of Connecticut,

Invasive Reference(s):

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External Links

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