Zostera japonica

Dwarf eelgrass

Family: Zosteraceae · Type: perennial · Not Native

Conservation status: Cal-IPC Yes

Dwarf eelgrass is a naturalized perennial herb found in northern California coastal areas, occurring in shallow bays and estuaries rooted generally 0 to 1 meters below mean low tide. Flowering from April to August, this marine plant produces small, inconspicuous flowers within its slender green leaves. Growing with thin, ribbon-like leaves up to 20 centimeters long and 1 to 2 millimeters wide, it develops two roots at each node along its underwater stems. Its leaf sheaths are distinctive, featuring open structures with two delicate membranous flaps that help distinguish it from native eelgrass species. This non-native aquatic plant has adapted efficiently to marine environments, spreading through its ability to root and grow in shallow coastal waters.

Habitat: Occ. Shallow water, bays, estuaries

Bloom period: Apr-Aug

Elevation: rooted generally 0-1 m below mean low tide

Bioregions: NCo, expected elsewhere

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.