Stems: apical internode shorter than adjacent one or almost absent. Leaf blades variable, rarely broadly ovate or suborbiculate. Inflorescences: branching from 2–10 nodes, mostly dichasial. Sepals not imbricate or broader beyond middle or, if imbricate, leaves not broadly ovate to suborbiculate. 2n = 16.

Phenology: Flowering summer–fall (Jun–Oct).
Habitat: Ditches, marshes, lake margins, desiccated temporary pools
Elevation: 0–400 m

Distribution

• Generated Map
• Legacy Map

B.C., N.B., N.S., Ont., Que., Sask., Ala., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., Ohio, Okla., Oreg., Pa., R.I., S.C., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., widely introduced in Central America, South America, Europe, Pacific Islands (Hawaii, New Zealand).

Discussion

The records of subsp. mutilum from British Columbia and Saskatchewan and from California, Colorado, Oregon, and Utah (no details seen) are almost certainly all the result of introduction, as may be some other peripheral records.

Selected References

None.

Lower Taxa

None.