Perennial herb 30 - 70 cm tall Leaves: opposite, stalkless, soft-hairy, finely bristled along the edges, longer than wide, and abruptly or gradually narrowed to a sharp, stiff point. The lower leaves are linear, while the upper leaves (just below the inflorescence) are lance-shaped, and 0.4 - 1 cm long. Inflorescence: terminal, somewhat loose and open branched, covered with slender, lustrous, multicelled, non-glandular hairs, and having twenty-four to fifty flowers with bracts scattered throughout. Flowers: short-stalked (stalks 0.5 - 1 cm long), purple, rarely pink or white, often with a more pale center, 1.5 - 2 cm wide, radially symmetric, with a slender tube, and abruptly flared lobes. The flowers have a faint fragrance. Sepals: five, 0.8 - 1.2 cm long overall, but fused for up to half their length, then separating into awl-shaped lobes with 0.5 - 1.5 mm long, stiff, bristle tips. The sepals are covered with very fine, 0.5 mm long, lustrous, silky hairs. Petals: five, but fused into a 1 - 1.5 cm long, very hairy tube, then separating into 1 cm long, 0.6 cm wide, narrowly inversely egg-shaped lobes with rounded tips. Stamens: five, with filaments attached at different heights along the inside of the petal tube, but never extending beyond the petal tube. Pistil: with a single, three-chambered, superior ovary; and three, short (1.5 - 3 mm long, usually shorter than stigmas or ovary), fused styles, which separate above the middle into three, linear stigmas. Fruit: a three-valved, three-chambered, egg-shaped capsule with one (rarely two), relatively large (up to 6 mm long), ellipsoid seed per chamber. Stems: somewhat stout, with horizontal, non-rooting, non-leafy shoots, and a few, erect, fertile shoots (with leaves and flowers), which are sparsely branched below the inflorescence, and covered with fine, non-glandular hairs.
Similar species: Phlox pilosa ssp. fulgida is one of five subspecies of P. pilosa in eastern North America. These five subspecies can be distinguished by the hairs of the inflorescence. There are only two subspecies in the Chicago Region, this one, which always lacks glandular hairs, and P. pilosa ssp. pilosa, which has evidently glandular hairs in the inflorescence.
Flowering: mid-May to July
Habitat and ecology: Abundant in prairie remnants with dry, loamy soils, and also seen in wetter, calcareous prairies.
Occurence in the Chicago region: native
Notes: This subspecies has been observed to attract small butterflies.
Etymology: Phlox is the Greek word for flame. Pilosa means covered in soft, long hairs. Fulgida means shiny or lustrous, referring to the covering of hairs along the stem and inflorescence.
Author: The Field Museum
From Flora of Indiana (1940) by Charles C. Deam
This is a variety with the inflorescence densely clothed with fine nonglandular hairs; calyx lobes broadish. I have a single specimen referable to this variety. It is from a roadside about 10 miles northwest of Fort Wayne. It was also found by Scott McCoy in Benton and Lake Counties. The range of the variety is in the prairies of the Upper Mississippi Basin to Manitoba.