Plants annual, from somewhat succulent roots. Stems 1-several, initially erect, often becoming prostrate or ascending, usually 1.5-3 dm. Leaves compound; blade with 2 orders of leaflets and lobes; ultimate lobes elliptic, variable in size, margins incised, apex subapiculate. Inflorescences racemose, commonly 6-10-flowered, equaling or barely exceeding leaves, sometimes poorly developed, cleistogamous-flowered racemes present, inconspicuous, 1-5-flowered; bracts elliptic, 6-12 × 3-7 mm, proximal bracts often leaflike or variously incised, distal reduced and entire. Flowers erect; pedicel slender, 6-15 mm or more; sepals lanceolate, ca. 1 mm; petals pale yellow, spurred petal 7-9 mm, spur incurved, ca. 2 mm, crest high, marginal wing well developed, both crest and wing wrinkled or dentate, unspurred outer petal similar to spurred petal, 6-8 mm; inner petals 5-7 mm, blade apex ca. 2 times wider than distinctly lobed base, claw 2-3 mm; nectariferous spur less than 1/2 length of petal spur; style 1.5-2 mm; stigma wider than long, with 4 terminal papillae. Capsules pendent, linear, straight or sometimes reflexed, (14-)18-20(-22) mm. Seeds ca. 2 mm diam., minutely decorated on narrow marginal ring. Flowering early-late spring. Wooded slopes, bottomlands, and rock outcrops, in moist, loose soil; 0-650 m; Ont.; Ala., Ark., Del., D.C., Fla., Ill., Ind., Iowa, Kans., Ky., La., Md., Mich., Miss., Mo., Nebr., N.J., N.Y., N.C., Ohio, Okla., Pa., S.C., Tenn., Va., W.Va.
From Flora of Indiana (1940) by Charles C. Deam
Local in the northern part of the state, becoming rather frequent in some of the Ohio River counties. It is found in rich, moist, sandy soil in woodland, usually on slopes and on the wooded bluffs of streams.
Green or glaucous annual 1-3 dm, at first erect, often becoming prostrate, the stem sympodial; racemes barely if at all exceeding the lvs; bracts ovate, foliaceous, 3-8 mm; cor pale yellow, 7-9 mm, incl. the 1-2 mm spur; crest of the upper pet usually toothed; frs spreading or drooping, 1.5-2 cm, on pedicels commonly (0.5-)1-1.5 cm; fls sometimes cleistogamous; seeds ca 2 mm wide, with a narrow, acute ring-margin; 2n=16. Moist soil; e. N.Y. to s. Ont., s. Mich. and S.D., s. to N.C., La., and Okla. Apr., May.
The Asian C. ophiocarpa Hook.f. & T. Thompson sometimes escapes from cult.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.