Detailed life-history studies of Uvularia perfoliata (D. F. Whigham 1974; D. K. Wijesinghe and D. F. Whigham 1997, 2001; H. Kudoh et al. 1999) have established the genetic basis of its clonal structure.
Perennial herb with a short, slender rhizome stem 15 cm - 0.5 m tall Leaves: alternate, pierced by the stem (perfoliate), 4 - 9 cm long, 1.5 - 4 cm wide, oval to oblong egg-shaped with a pointed tip, with a waxy coating (glaucous) on the lower surface. Two to four leaves grow beneath the fork of the stem. Flowers: one per stem, terminal (but appearing axillary), nodding, pale yellow, narrowly bell-shaped, conspicuously glandular within, with six distinct tepals. Tepals over-lapping, 2 - 3.5 cm long, 3 - 5 mm wide, elongate, not twisted, with a pointed tip. Flower stalk 1 - 2 cm long, with a single, fused bract. Stamens six, 1 - 1.5 cm long. Fruit: a three-lobed capsule, greenish to yellowish brown, egg-shaped. Seeds brownish red, nearly spherical. Stems: one to several, upright, forked above the middle, with a waxy coating (glaucous).
Similar species: The perfoliate leaves distinguish this species and Uvularia grandiflora from U. sessilifolia. Uvularia grandiflora differs by having hairy-veined leaf undersides and few, if any, glands inside its bright yellow flowers.
Habitat and ecology: This eastern U.S. species is rarely found in the Chicago Region. Its typical habitat is woods.
Occurence in the Chicago region: native
Etymology: Uvularia comes from the word uvula (the soft lobe that dangles at the back of the throat) of which the drooping flowers resemble. Perfoliata means "with the leaf embracing or surrounding the stem."
Stem 2-4 dm at anthesis, later taller, forking above, bearing 2-4 lvs below the fork, 1-4 on the sterile branch, and several lvs and 1-3 fls on the fertile branch; lvs perfoliate, oval to lance-oblong, to 9 cm, glabrous beneath; fls yellow; tep 17-25 mm, acute or acuminate, conspicuously glandular-papillose within; 2n=14. Moist woods, preferring acid soils; s. N.H. to s. Ont., and O., s. to S.C., Ga., w. Fla. and e. Tex. May, June.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.