parrotfeather
(Myriophyllum aquaticum)
This species is Introduced in the United States
Appearance
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.
Foliage
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.
Flowers
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).
Fruit
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.
Resources
- Fact Sheet - Ontarios Invading Species Awareness Program
- Global Invasive Species Database - Invasive Species Specialist Group
- Plant Invaders of Mid-Atlantic Natural Areas - National Park Service and U.S. Fish and Wildlife Service
Selected Images
Maps
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 Lists - This map identifies those states that have this species on their invasive species list or law.
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 Invasive Species Council
- Georgia Exotic Pest Plant Council - Category 2
- Idaho Noxious Weeds
- Indiana Invasive Species Council - Invasive Plant List
- Indiana Pest Species
- Indiana Prohibited Plant Species
- Invasive Plant Species of West Virginia
- Invasive Species of Concern in Georgia
- Jil M. Swearingen, Survey of invasive plants occurring on National Park Service lands, 2000-2007
- Maryland Aquatic Nuisance Species Plan
- Maryland Code and Regulations Nonative Aquatic Organisms
- Maryland Department of Natural Resources Policy: Restriction on Planting Exotic Invasive Plants
- Maryland Invasive Species Council - Invasive Species of Concern in Maryland
- Massachusetts Invasive Plants Advisory Group List
- Massachusetts Noxious Weeds
- Massachusetts Prohibited Plant List
- Michigan’s Invasive Species Watch List
- Michigan’s Prohibited and Restricted Species
- Mid-Atlantic Field Guide to Aquatic Invasive Species
- Minnesota DNR invasive species list
- Montana Noxious Weeds
- National Park Service, Mid-Atlantic Exotic Plant Management Team Invasive Plant List
- National Park Service, National Capital Region Exotic Plant Management Team Invasive Plant List
- 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
- New Jersey Invasive Species Strike Team 2017 Invasive Species List
- New Mexico Noxious Weeds
- New York Regulated and Prohibited Invasive Species - Prohibited
- Non-Native Invasive Plants of Arlington County, Virginia
- Non-Native Invasive Plants of the City of Alexandria, Virginia
- Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
- Ontario’s Invading Species Awareness Program Tracked Species List
- Oregon Noxious Weeds
- Pacific Northwest Exotic Pest Plant Council, 1998
- Pennsylvania Department of Conservation and Natural Resources Invasive Plants
- Pennsylvania Noxious Weeds
- Pennsylvania's Field Guide to Aquatic Invasive Species
- Plant Invaders of Mid-Atlantic Natural Areas
- Rhode Island Natural History Survey
- South Carolina Invasive Pest Council
- Tennessee Exotic Pest Plant Council
- Texas Noxious Weeds
- Utah Noxious Weeds
- Vermont Noxious Weeds
- Virginia Invasive Plant Species List
- Washington Noxious Weeds
- WeedUS - Database of Plants Invading Natural Areas in the United States
- West Virginia Invasive Species Strategic Plan and Volunteer Guidelines 2014
- West Virginia Native Plant Society, Flora West Virginia Project, and West Virginia Curatorial Database System, September 3, 1999
- Wisconsin Noxious Weeds
- Wisconsin's Invasive species rule – NR 40
Taxonomic Rank
| Domain: Eukarya |
| Kingdom: Plantae |
| Phylum: Magnoliophyta |
| Class: Magnoliopsida |
| Superorder: Saxifraganae |
| Order: Saxifragales |
| Family: Haloragaceae |
| Genus: Myriophyllum |
| Myriophyllum aquaticum |
Synonyms and Other Names
Other Common Names:
parrotfeather watermilfoil, water-feather, Brazilian water-milfoil, parrotfeather
Related Scientific Names:
Enydria aquatica (Vell.) Verdc. (Synonym)
Myriophyllum brasiliense (Vell.) Verdc. (Synonym)
Myriophyllum proserpinacoides (Vell.) Verdc. (Synonym)
References
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.