Much like no. 1 [Strophostyles helvula (L.) Elliott]; perennial; lfls 2-5 cm, never lobed, but occasionally with barely concave lateral margins, pilose beneath, glabrous or minutely short-hairy above; bracteoles ovate or oblong, blunt, to half as long as the cal-tube; seeds 3-5 mm, rarely longer; 2n=22. Dry, sandy, upland woods; s. N.Y. to Fla. and Tex., chiefly on the coastal plain, n. in the interior to s. Ind., Mo., and Okla.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
This species is rare to infrequent and has the habitat of the preceding species. It is possibly restricted to the southern counties. The specimens collected and reported from Marshall and Putnam Counties were found in ballast along railroads and may be introduced. All of my specimens are from wooded slopes and fallow fields.
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Indiana Coefficient of Conservatism: C = 4
Wetland Indicator Status: FACU
Diagnostic Traits: perennial vine with trifoliate leaves; leaflets oblong or narrowly ovate, unlobed, pilose beneath; bracteoles about half as long as adjacent calyx tube; calyx 4-lobed, glabrous; legumes rounded, 3-6 cm.