flowering-rush USDA PLANTS Symbol: BUUM
U.S. Nativity: Exotic
Habit: Aquatic Plants Forbs/Herbs
Butomus umbellatus L.

Jump to: Resources | Images | Distribution Maps | Sources
Taxonomic Rank: Liliopsida: Alismatales: Butomaceae
Synonym(s): grassy rush, water gladiolus
Native Range: Eurasia (BAIL);

Butomus umbellatus is a perennial which spreads primarily from rhizomes. This aquatic plant invades along the margins of slow moving waterways. This plant can reach from 1-5 ft. (0.3-1.5 m) in height and can survive in water of up to 9.8 ft. (3 m) deep. It does not tolerate salt water.
The leaves are linear, up to 3.2 ft. (1 m) long and triangular and fleshy in cross-section. The leaves may be erect or floating on the surface of the water.
Flowering occurs in June to August, when umbels of small, 0.75-1 in. (1.9-2.5 cm) wide, pink to white flowers develop.
The fruit is beaked which split at maturity to release the seeds. The seeds float which allows them to be easily dispersed by water.
Ecological Threat
This plant spreads mostly from rhizomes and occurs in wet areas with muddy soil, such as freshwater marshlands, lakes and streams. Butomus umbellatus can displace native riparian vegetation. It can form dense stands which are an obstacle to boat traffic. It is tolerant of a wide range of temperatures which gives it the potential to invade across much of the United States. Butomus umbellatus is native to Eurasia and was first found in Canada in the late 1800’s and in the United States in the early 1900’s.

Identification, Biology, Control and Management Resources

Selected Images from Invasive.orgView All Images at Invasive.org

Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Additional Resolutions & Image Usage

Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Additional Resolutions & Image Usage

Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Additional Resolutions & Image Usage

Steve Hurst, USDA NRCS PLANTS Database, Bugwood.org
Additional Resolutions & Image Usage

EDDMapS Distribution:
This map is incomplete and is based only on current site and county level reports made by experts and records obtained from USDA Plants Database. For more information, visit www.eddmaps.org

State(s) Where Reported invasive.
Based on state level agency and organization lists of invasive plants from WeedUS database.

Invasive Listing Sources:
Connecticut Invasive Plant Working Group
Faith Campbell, 1998
Hoffman, R. & K. Kearns, Eds. 1997. Wisconsin manual of control recommendations for ecologically invasive plants. Wisconsin Dept. Natural Resources, Bureau of Endangered Resources. Madison, Wisconsin. 102pp.
New Hampshire Invasive Species Committee. 2005. Guide to Invasive Upland Plant Species in New Hampshire. New Hampshire Department of Agriculture,  Markets and Food Plant Industry Division and New Hampshire Invasive Species Committee.
Vermont Department of Environmental Conservation