Page author: David Giblin
Myriophyllum aquaticum
parrot's feather, water feather, South American water milfoil
WTU specimens
Other herbaria

Distribution: Occurring on both sides of the Cascades crest in Washington; widely distributed throughout much of North America.

Habitat: Ponds and slow-moving streams.

Flowers: May-July

Origin: Introduced from South America

Conservation Status: Not of concern

Description:
General:

Perennial, aquatic herbs, the stems sturdy, 2-4 mm. thick and 1-9 dm. long, completely submerged until time of flowering.

Leaves:

Leaves in whorls of 4-6, all finely pinnatifid, 2.5- 5 cm. long, the 25-37 divisions filiform; stipules linear.

Flowers:

Flowers in the axils of submerged leaves along the main stem, with minute, linear to filiformly dissected bracteoles; sepals 4, attached to the top of the inferior ovary; staminate flowers with 4 small petals and 8 stamens; pistillate flowers with no petals, the stigmas plumose.

Fruits:

Achene 1.5-2 mm. long.

Accepted Name:
Myriophyllum aquaticum (Vell.) Verdc.

Synonyms & Misapplications:
Myriophyllum brasiliense Cambess. [HC]
Myriophyllum proserpinacoides Gillies ex Hook. & Arn.
Additional Resources:

PNW Herbaria: Specimen records of Myriophyllum aquaticum in the Consortium of Pacific Northwest Herbaria database.

WA Flora Checklist: Myriophyllum aquaticum checklist entry.

E-Flora BC: Myriophyllum aquaticum atlas page.

CalPhotos: Myriophyllum aquaticum photos.

USDA Plants: Myriophyllum aquaticum information.

17 photographs:
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