Slender, woody, high-climbing; lvs variable, even on the same plant, lanceolate to broadly obovate, 5-12 cm, on petioles 2-15 mm; cymes long-peduncled, many-fld, produced in only one axil of a pair of lvs; cor-tube 6 mm, the lobes 3-4 mm; fr 15-25 cm. Moist or wet woods on the coast plain; Del. to Tex., n. in the interior to sw. Ind. and se. Mo. July.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
A climbing vine, herbaceous in Indiana, growing in compact, clay soil in low, open woods in southwestern Indiana. The flowers are yellowish and very fragrant. The first specimen I ever found was detected by its odor. I noted a peculiar, pungent fragrance and in searching for the source I found this vine, at least a rod distant. Very rare in our area.
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Indiana Coefficient of Conservatism: C = 8
Wetland Indicator Status: FACW
Diagnostic Traits: vines; leaves opposite, varying from lanceolate to broadly obovate; flowers in axillary cymes, corolla trumpet-shaped, yellow; follicles 10-23 cm long, slender, pendulous.