Robust hemiparasitic perennial 1-2 m, somewhat hairy; lvs opposite, the lower broadly ovate, 2-4 dm, deeply pinnatifid or bipinnatifid, the upper progressively reduced to lanceolate and entire; fls sessile or subsessile in the upper axils, forming elongate, interrupted, leafy spikes; cal 6-10 mm; cor ephemeral, yellow, 1.5 cm, the tube ampliate, longer than the spreading lobes, densely villous within; fr 6-11 mm; seeds 2-2.5 mm. Moist rich woods; O. and c. Pa. to Io. and Kans., s. to Ga. and Tex. June-Sept. (Seymeria m.; Afzelia m.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.