Plants 40-180 cm. Corms globose. Stems glabrous. Leaves: basal and proximal cauline (mostly arising from congested nodes) 1-nerved, lance-linear to linear, 100-380 × (1-)2-6(-9) mm, abruptly reduced distally, glabrous (minutely white-dotted by stomates), weakly, if at all, gland-dotted (glandular hairs usually not evident). Heads in compact, racemiform arrays. Peduncles (ascending) 1-7 mm. Involucres turbinate-campanulate, 5-7 × 4-5 mm. Phyllaries in 2-3(-4) series, lanceolate to oblong or elliptic-oblong, unequal, essentially glabrous, margins with hyaline borders, apices usually rounded-retuse and minutely involute-cuspidate to apiculate. Florets 3-5; corolla tubes glabrous inside. Cypselae 2.5-4 mm; pappi: lengths ± equaling corollas, bristles barbellate.

Flowering Aug-Oct(-Nov). Sand ridges and flats, roadsides, pine woods, sand pine-scrub, longleaf pine-scrub oak; 0-100 m; Fla., Ga.

R. P. Wunderlin (1998) treated Liatris laevigata and L. tenuifolia as varieties in one species; A. Cronquist (1980, p. 207) also treated them within one species, as 'two well-marked but wholly confluent geographic vars.' They have been noted to grow intermixed in Osceola County, Florida (L. laevigata, Ray et al. 10472, NCU; L. tenuifolia, Ray et al. 10423, NCU). Unequivocal intermediates have not been seen in the present study. With the observation of consistent morphologic differences in habit, vestiture, and leaf punctation, and their broad sympatry in Florida, it seems appropriate to recognize them at specific rank.

Liatris laevigata is restricted to peninsular Florida and immediately adjacent Georgia (e.g., Floyd´s Island, Charlton County, Cypert 240, SMU). Leaf width is markedly variable, and collections of narrow-leaved forms sometimes have been identified as L. tenuifolia. Narrow-leaved forms of L. laevigata apparently are more common in southern Florida (Collier, Dade, Glades, Lee, Monroe, Okeechobee, Palm Beach, and Polk counties). Broader-leaved plants apparently tend to have larger corms, which may be related to age or habitat.