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Taxon  Report  
Najas marina  L.
Marine water nymph,   Spiny naiad
Najas marina is an annual herb that is native to California.
Siskiyou Del Norte Modoc Humboldt Shasta Lassen Trinity Plumas Tehama Butte Mendocino Glenn Sierra Yuba Lake Nevada Colusa Placer Sutter El Dorado Yolo Alpine Napa Sonoma Sacramento Mono Amador Solano Calaveras Tuolumne San Joaquin Marin Contra Costa Alameda Santa Cruz Mariposa Madera San Francisco San Mateo Merced Fresno Stanislaus Santa Clara Inyo San Benito Tulare Kings Monterey San Bernardino San Luis Obispo Kern Santa Barbara Ventura Los Angeles Riverside Orange San Diego Imperial

Bloom Period
Genus: Najas
Family: Hydrocharitaceae  
Category: angiosperm  
PLANTS group:Monocot
Jepson eFlora section: monocot

Wetlands: Occurs in wetlands

Communities: wetland-riparian

Name Status:
Accepted by JEF + PLANTS

Alternate Names:
PLANTSNajas gracilis
PLANTSNajas major var. angustifolia
PLANTSNajas major
PLANTSNajas marina var. recurvata
Information about  Najas marina from other sources
Nursery availability from CNPLX
Commercial availability unknown.
Jepson eFlora


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[Wikipedia] Description, Distribution, Habitat: Description Najas marina is an annual producing a slender, branching stem up to 40 or 45 centimeters in maximum length. The evenly spaced leaves are up to 4 centimeters long, 1 to 3 millimeters wide, and edged in tiny sawlike teeth. The leaf has prickles along its midvein. Minute stalkless, green flowers occur in the leaf axils. The plant is dioecious, with male and female flower types occurring on separate individuals.[6][4][5][7][8] In the British Isles it is possible that only female plants occur. It flowers in mid-summer.[9] Distribution and habitat Najas marina has a wide, almost circumglobal distribution in temperate and tropical regions. It occurs in mesoeutrophic water over deep peat or mud. It was first recorded in the British Isles in 1883 at Hickling Broad in Norfolk where it had become established. Populations declined in the 1960s because of pollution, but action has been taken to reduce the level of nutrients in the Norfolk Broads and the water quality has improved.[11] (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: 05/21/2024).