Plants solitary or in groups, with thick, fleshy rhizomes. Leaves basal; petiole indistinct, flattened, 3-10 cm; blade linear or elliptic to ovate, 6-25 cm, fleshy, base attenuate, margins entire or subentire, ciliate, surfaces usually densely short-hairy, often tangled brown-hairy along proximal midveins. Inflorescences (30-)50+-flowered, open, often lax thyrses, 25-125 cm, purple-tipped stipitate-glandular. Flowers: sepals reflexed, triangular to ovate; petals white to cream or rarely purple, not spotted, linear to narrowly elliptic, not clawed or slightly clawed, 2-3 mm, longer than sepals; filaments linear, flattened; pistils connate to 1/2 their lengths; ovary 1/2+ inferior, appearing superior in fruit. Capsules green, folliclelike. 2n = 56, 84, 112. Flowering spring. Marshy meadows, mucky seepages in woods, swamp forests, montane bogs and seeps; 100-1400 m; Man., Ont., Sask.; Conn., Del., Ill., Ind., Iowa, Ky., Maine, Md., Mass., Mich., Minn., Mo., N.H., N.J., N.Y., N.C., Ohio, Pa., R.I., Tenn., Vt., Va., W.Va., Wis. Purple-petalled populations of Micranthes pensylvanica have been known as Saxifraga purpuripetala and are found in Maine, New York, Pennsylvania, and Vermont.
Perennial herb 30 cm - 1.5 m tall Leaves: basal, short-stalked, to 20 cm long, spoon-shaped to oblong or lance-shaped, non-toothed or toothed, slightly hairy, leathery. Flowers: borne on an inflorescence that is compact when young but becoming loose and elongate with age. Each flower has reflexed sepal lobes, greenish white or purple petals (2 - 3 mm long) with one or three veins, and ten stamens. Fruit: dry, inflated, opening along one side (follicle), 3 - 5 mm long. Each cluster of follicles is attached at least to the middle. Flowering stem: erect, somewhat stout, finely grooved, hairy, leafless.
Similar species: Parnassia glauca has leaves reaching twice as long as wide, a hairless flowering stem, and solitary flowers with five stamens and a single-chambered ovary.
Flowering: early May to late June
Habitat and ecology: Local in moist habitats such as calcareous springs, boggy places in the dune area, moist meadows, and upland swamps.
Occurence in the Chicago region: native
Etymology: Saxifraga comes from the Latin words Saxum meaning rock, and frango meaning "to break." Pensylvanica means "from Pennsylvania."
Erect, 3-10 dm; lvs all basal, entire to glandular- denticulate or obscurely serrulate, sparsely hairy, the larger ones 10-20 cm; infl at first compact, later usually lax and elongate; sep soon reflexed; pet greenish-white or purple, 2-3 mm, 1-nerved or 3-nerved, narrowly lanceolate to lance-ovate; body of the follicles erect, connivent at least to the middle, the styles erect or divergent; diploids and polyploids to 14x, based on x=14. Wet meadows and bogs; Me. to Minn., s. to Va. and Mo. May, June. (Micranthes p.; S. forbesii)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.