Tahoe draba, Draba asterophora

Kuvaus:

Tahoe draba, Draba asterophora, Slide Mountain, Sierra Nevada, Carson Range, Humboldt Toiyabe National Forest, elevation 2690 m (8830 ft). Substrate is rocky granitic colluvium. Also visible are needles of lodgepole pine (Pinus contorta subsp. murrayana).This rare plant is known only from the Mount Rose and Slide Mountain areas of the northern Carson Range in extreme western Nevada, in and just outside of the Lake Tahoe drainage basin. The diploid progenitor of this autotetraploid species survives in a separate population at the south end of the Carson Range in the Heavenly Mountain and Freel Peak areas on either side of the California-Nevada border. An auto-octoploid named var. macrocarpa comprises a third isolated population in the Cup Lake area of California.