Liatris punctata var. punctata

Corms elongate or becoming rhizomes. Leaves 10–14 cm, 1–4 (–5) mm wide. Heads in dense, spiciform arrays (closely spaced, stems usually obscured by heads). Involucres 10–14 mm. Phyllaries in 4 (–5) series. Florets 4–8.2n = 20, 40, 60.

Phenology: Flowering Aug–Oct(–Nov).
Habitat: Grassy prairies, sagebrush prairies, rocky and gravelly ridges and slopes, roadsides, fencerows, stream banks, over granite, limestone, and sandstone, in sands, clays, gypseous clays
Elevation: (50–)100–1900(–2200) m

Alta., Man., Sask., Colo., Ill., Iowa, Kans., Mich., Minn., Mo., Mont., Nebr., N.Mex., N.Dak., Ohio, Okla., S.Dak., Tex., Wis., Wyo.

Discussion

Gaiser distinguished var. punctata (type from Saskatchewan) from var. nebraskana by its thicker, often shorter stems, broader and shorter leaves, leaves and phyllaries with ciliate margins, and phyllaries with lanceolate-acuminate apices. Weak geographic trends exist in these features; variability renders var. nebraskana largely typological and necessitates much arbitrary identification. B. R. Menhusen (1963) also did not find justification for recognizing var. nebraskana. Variation in chromosome number may be associated with some of the apparent polymorphism.

Liatris densispicata was described from sand dunes in Minnesota. It was said to have “an elongate rootstock that runs horizontally in the sand, giving off clusters of aerial stems,” and to differ from L. punctata by “the generally finer and more slender structure of the stem, spike, and leaves” (L. O. Gaiser 1946, p. 363). It was listed as a synonym of L. punctata by G. B. Ownbey and T. Morley (1991).

Selected References

None.

Lower Taxa