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

Our only specimens are from a wooded bluff along the Ohio River about 6 miles above Cannelton and from a wooded bluff in Jefferson County. I reported Oxalis Brittoniae Small from Steuben and Wells Counties. (Proc. Indiana Acad. Sci. 1904: 220. 1905.) I am now referring these specimens to Oxalis europaea Jordan. Pepoon reported Oxalis filipes Small from Lake and Porter Counties for Umbach but Fassett (Rhodora 35: 200. 1933) refers the Lake County specimen to Oxalis stricta and says there is no specimen labeled Oxalis filipes from Porter County.

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Indiana Coefficient of Conservatism: C = 0

Wetland Indicator Status: N/A

Diagnostic Traits: Stems mostly erect, mostly less than 30 cm, pilose to glabrous but lacking septate hairs; leaves alternate, trifoliate; flowers mostly 1-2 per cyme; petals yellow, 4-11 mm; capsule fruits 8-12 mm, glabrous to sparsely puberulent, not villous.