Penstemon linarioides var. sileri

A. Gray

in A. Gray et al., Syn. Fl. N. Amer. 2(1): 270. 1878. (as Pentstemon)

Endemic
Synonyms: Penstemon linarioides subsp. sileri (A. Gray) D. D. Keck P. linarioides var. viridis D. D. Keck
Treatment appears in FNA Volume 17. Treatment on page 105. Mentioned on page 104.

Stems 8–40 cm. Leaves glabrous, glabrate, retrorsely hairy, or puberulent, hairs pointed, cauline 8–26 × 0.5–2 mm, blade linear. Flowers: staminode: distal 3–5 mm densely pilose, hairs yellow, to 1.2 mm, rest of distal 2–3 mm sparsely to moderately pilose.


Phenology: Flowering May–Sep(–Oct).
Habitat: Sandy to clay soils, sagebrush shrublands, oak or oak-juniper woodlands, pine forests.
Elevation: 1200–2400 m.

Discussion

Variety sileri is known from northern Arizona, southern Nevada, and southwestern Utah. Plants with glabrous or nearly glabrous leaves from northern Arizona and southern Utah have been referred to var. viridis. As noted by N. H. Holmgren (1984), such forms occur sporadically through much of the range of var. sileri, suggesting that taxonomic recognition of var. viridis is unwarranted. Some specimens included in var. sileri from northern Arizona, especially from the Kaibab Plateau, have the habit of subsp. compactifolius (included here in var. linarioides) but the leaf pubescence of var. sileri (or var. viridis). Holmgren identified three morpho-geographic races that may warrant recognition.

Selected References

None.

Lower Taxa

None.
Craig C. Freeman +
A. Gray +
Penstemon +
Ariz. +, Nev. +  and Utah. +
1200–2400 m. +
Sandy to clay soils, sagebrush shrublands, oak or oak-juniper woodlands, pine forests. +
Flowering May–Sep(–Oct). +
in A. Gray et al., Syn. Fl. N. Amer. +
Penstemon linarioides subsp. sileri +  and P. linarioides var. viridis +
Penstemon linarioides var. sileri +
Penstemon linarioides +
variety +