Woody climber with glabrous branches; lvs not glaucous, the lower oblanceolate to broadly oval, acute or obtuse, the uppermost pair connate into an oval or subrotund disk with obtuse ends; fls golden to orange, 3-3.5 cm; cor-tube glabrous outside, glabrous or sparsely hairy inside, gradually expanded upwards, about as long as the lips; style glabrous; 2n=18. Rocky woods and thickets; s. Mo. and Ky. to N.C., Ga., and Ark. Apr., May. Plants with the cor merely yellow, mostly shorter, and more hairy within have been distinguished as var. flavescens (Small) Gleason. They may be hybrids with L. prolifera. (L. flavescens Small, not Dippel; L. flavida)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.