Calflora, a 501c3 non-profit
Distribution by County   2893    
Egeria densa  Planch.
Brazilian water weed,   Brazilian waterweed
Egeria densa is a perennial herb that is not native to California.
Cal-IPC rating: high
Record Count by County

Alameda: 6 Kern: 1 Placer: 3 Solano: 5
Amador: 1 Lake: 4 Sacramento: 32 Sonoma: 13
Butte: 12 Los Angeles: 5 San Diego: 2 Stanislaus: 2
Calaveras: 4 Madera: 3 San Francisco: 3 Sutter: 5
Colusa: 1 Marin: 14 San Joaquin: 23 Tulare: 1
Contra Costa: 16 Mariposa: 1 San Luis Obispo: 1 Tuolumne: 2
El Dorado: 3 Merced: 7 San Mateo: 2 Yolo: 9
Fresno: 4 Mono: 11 Santa Clara: 2 Yuba: 8
Imperial: 1 Napa: 9 Santa Cruz: 2
Inyo: 1 Nevada: 2 Shasta: 4

Suggested Citation
Calflora: Information on California plants for education, research and conservation, with data contributed by public and private institutions and individuals, including the Consortium of California Herbaria. [web application]. 2026. The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: 01/19/2026).