Cirsium hydrophilum var. hydrophilum
Heads usually 2.5–3 cm. Cypselae oblong, ca. 5 mm. 2n = 32.
Phenology: Flowering spring–summer (May–Sep).
Habitat: Tidal marshes
Elevation: 0–5 m
Of conservation concern.
Suisun thistle is known only from the Suisun Marsh (Solano County) in the Sacramento River delta.
Variety hydrophilum is listed by the U.S. Fish and Wildlife Service as endangered.
"fine" is not a number."broad" is not a number.