- Myriophyllum aquaticum is an herbaceous, rooted, submerged to emergent plant that invades aquatic habitats throughout much of the United States. Stems are stout and blue-green in color.
- Leaves are abundant, whorled, pinnately compound, and finely dissected. Submersed leaves are 0.6-1.4 in. (1.5-3.5 cm) long and have 20 to 30 divisions per leaf. Emergent leaves are 0.8-2 in. (2-5 cm) long, less divided and greener than the submersed leaves.
- As only female plants occur in North America, reproduction occurs vegetatively. Inconspicuous flowers are formed in the axils of the emergent leaves in the spring (sometimes fall).
- No fertile fruit is known to be produced in the United States.
- Ecological Threat
- Myriophyllum aquaticum's potential range is yet to be determined. In more southern regions, this plant forms monocultures that clog waterways, impeding recreational and commercial boating activities. These monocultures also disrupt the growth of native aquatic plants and provide breeding areas for mosquitoes. Myriophyllum aquaticum is a common water garden plant, which has the potential to escape into local waterways. Control of this plant is extremely costly.
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EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit www.eddmaps.org
State Invasive List - This map identifies those states that list this species on their invasive species list. For more information, visit Invasive.org
Most Troublesome / Most Common Agricultural Weed List
This map identifies those states that consider this species either most troublesome or most common in at least one commodity. For more information, visit the MTMC project page.
|No Data for this state|
|Troublesome or Common weed in one or more crops|
Invasive Listing Sources
- Alabama Invasive Plant Council
- Alabama Noxious Weeds - Class C Noxious Weed
- Apalachicola Invasive Working Group
- California Invasive Plant Council
- Colorado Noxious Weeds
- Connecticut Invasive Plant List
- Connecticut Invasive Plant Working Group
- Delaware Natural Resources and Environmental Control, 2004
- East Central Florida CISMA
- EDDMapS Ontario
- Faith Campbell, 1998
- Georgia Exotic Pest Plant Council - Category 2
- Idaho Noxious Weeds
- Jil M. Swearingen, Survey of invasive plants occurring on National Park Service lands, 2000-2007
- Maine Noxious Weeds
- Maryland Department of Natural Resources, 1994
- Massachusetts Noxious Weeds
- Mid-Atlantic Exotic Pest Plant Council, 2005
- 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.
- New Hampshire Prohibited Aquatic Species
- Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
- Oregon Noxious Weeds
- Tennessee Exotic Pest Plant Council
- Vermont Noxious Weeds
- Virginia Invasive Plant Species List
- Washington Noxious Weeds
- WeedUS - Database of Plants Invading Natural Areas in the United States
- Wisconsin's Invasive Species Identification, Classification and Control Rule
|Common Name Reference:|| USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA, USA.|
|Scientific Name Reference:||USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA, USA.|