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Taxon  Report  
Myriophyllum spicatum  L.
American milfoil,   Eurasian milfoil,   Spike watermilfoil,   Water milfoil
Myriophyllum spicatum is a perennial herb that is not native to California.
Cal-IPC rating: high
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Observation Search
~685 records in California
redone or more occurrences
within a 7.5-minute quadrangle

Bloom Period
Genus: Myriophyllum
Family: Haloragaceae  
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Wetlands: Occurs in wetlands

Communities: wetland-riparian

Name Status:
Accepted by JEF + PLANTS

Information about  Myriophyllum spicatum from other sources

[www.invasive.org/] Ecological Threat, Invasiveness: Water-milfoil tends to invade disturbed areas and does not typically spread into undisturbed areas where native plants are well established. It can form large, floating mats of vegetation on the surface of lakes, rivers and other water bodies, that impede water traffic and reduce light for native aquatic species. It thrives in areas that have been subjected to natural and man-made disturbance. (contributed by Mary Ann Machi)

[Wikipedia] Europe, Asia, north Africa native: Myriophyllum spicatum (Eurasian watermilfoil[1] or spiked water-milfoil) is native to Europe, Asia, and north Africa, but has a wide geographic and climatic distribution among some 57 countries, extending from northern Canada to South Africa.[2] It is a submerged aquatic plant, grows in still or slow-moving water, and is considered to be a highly invasive species. (contributed by Mary Ann Machi)

Suggested Citation
Calflora: Information on California plants for education, research and conservation, with data contributed by public and private institutions and individuals. [web application]. 2024. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: 05/19/2024).