Myriophyllum aquaticum
Parrot's feather, Parrot's Feather
Family: Haloragaceae · Type: Herb · Not Native
Conservation status: Cal-IPC Yes
Myriophyllum aquaticum (Parrot's feather) is a non-native California herb in the Haloragaceae family, recognized by stem color, leafiness, and leaf segment count.
Parrot's feather is a naturalized perennial found in northern and central California regions including the Coast Ranges, Sierra Nevada Foothills, Central Valley, San Francisco Bay Area, and Mojave Desert in ponds, streams, and lakes at elevations below 500 meters. Flowering from July to September, this aquatic plant produces small, inconspicuous flowers in terminal emergent inflorescences. Growing with bright green to grayish-green stems less than one meter long, it forms dense, leafy mats throughout water bodies. Its finely dissected underwater leaves have 20 to 30 segments, each approximately 7 millimeters long, creating a delicate, feather-like appearance. This dioecious plant is notable for its ability to spread extensively in aquatic habitats, with no viable fruit production in California.
Identification and appearance
Key characters: 4 sympatric species; distinguished by stem color, leafiness, and leaf segment count
Habitat and range
Habitat: Common. Ponds, streams, lakes
Elevation: < 500 m
California counties: Kings, Marin, San Francisco, San Mateo, Monterey, Sutter, San Luis Obispo, Humboldt, Kern, San Bernardino, Los Angeles, Butte, Sonoma, Placer, Merced, Stanislaus, Glenn, Mendocino, Tulare, Shasta, Yuba, Tehama, San Diego, Napa, Contra Costa, Trinity, Del Norte, San Joaquin, El Dorado
Outside California: southern and eastern United States, warm temperate, tropics worldwide, native to South America
Bloom period
Myriophyllum aquaticum blooms Jul-Sep.
Conservation status
Cal-IPC Yes
How to tell it apart
vs Hippuris: Myriophyllum has feathery divided leaves; Hippuris has simple, undivided linear leaves in whorls.; vs Elodea: Myriophyllum has leaves pinnately divided into thread-like segments; Elodea has simple oval leaves.; vs Ceratophyllum: Myriophyllum leaves fork from a central spine; Ceratophyllum leaves fork repeatedly without central axis.; vs Ranunculus: Myriophyllum has whorled feathery leaves; aquatic Ranunculus has alternate or basal divided leaves.; vs Potamogeton: Myriophyllum has feathery divided leaves; Potamogeton has simple, entire leaves (blade-like or oval).
Frequently asked questions
Is Myriophyllum aquaticum native to California?
No. Myriophyllum aquaticum is not native to California (recorded as not native).
When does Myriophyllum aquaticum bloom?
Myriophyllum aquaticum blooms Jul-Sep.
Where in California does Myriophyllum aquaticum grow?
Myriophyllum aquaticum occurs in Kings, Marin, San Francisco, San Mateo, Monterey, Sutter, San Luis Obispo, Humboldt and other counties, at elevations of < 500 m.
What plant family does Myriophyllum aquaticum belong to?
Myriophyllum aquaticum is in the Haloragaceae family, genus Myriophyllum.
Is Myriophyllum aquaticum invasive in California?
Myriophyllum aquaticum is listed by Cal-IPC with an invasiveness rating of Yes.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.