From Flora of Indiana (1940) by Charles C. Deam

Infrequent throughout the lake area in marshes, along moist roadsides, and on the low borders of lakes. Smith's report from Clark County should be referred to the preceding species. This species is often confused with Lathyrus palustris. (See that species for discussion.)

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Indiana Coefficient of Conservatism: C = 6

Wetland Indicator Status: FACU