Taxon  Report   4279    
Hydrilla verticillata  (L. f.) Royle
Hydrilla,  Waterthyme
Hydrilla verticillata
© 2001 CDFA
Photos from
CalPhotos / Calflora
Hydrilla verticillata
© 2001 CDFA
Hydrilla verticillata
© 2001 CDFA
Hydrilla verticillata, a monocot, is a perennial herb that is not native to California; it was introduced from elsewhere and naturalized in the wild. Cal-IPC rating: High

Hydrilla verticillata is classified by the U.S. Federal Government as a NOXIOUS WEED. [USDA 2000]

Interactive Distribution Map

Observation Hotline
(observation details)

point, line, or polygon

one or more occurrences
within a 7.5-minute quadrangle

Plant Characteristics
and Associations

Bloom Period
Hydrilla verticillata
© 2001 CDFA
Genus: Hydrilla
Communities: wetland-riparian

Wetlands: Occurs in wetlands

Name Status:
Accepted by JEF + PLANTS

More information about  Hydrilla verticillata
Photos on Google Images
Jepson eFlora

Records from the Consortium of California Herbaria

ITIS Original Publication citation


Search the International Plants Names Index

Search (Flora of North America)

website references from Google

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]. 2019. Berkeley, California: The Calflora Database [a non-profit organization]. Available:   (Accessed: Jan 20, 2019).