Few low-growing shrubs survive above timberline |
Tundra (Alpine Life Zone)
Non-technical description: The Alpine Life Zone is characterized by low-growing vegetation (prostrate shrubs, grasses, and forbs)
on the highest mountaintops where the climate (primarily wind and cold) is too hostile for trees.
The Alpine Tundra zone occurs at the highest elevations where the climate is brutal, and the growing season is short and
interrupted. Trees are absent. The vegetation is dominated by low-growing forbs, sedges, bunchgrasses,
and short-stemmed woody shrubs. Common forb species include alpine avens (Geum rossii), Silene acaulis, Eriogonum spp., Draba spp.; sedges include various species of Carex; grasses include tufted hair grass (Deschampsia caespitosa), Trisetum spicatum, Agropyron scribneri, Festuca ovina, Phleum alpinum; and shrubs include willow (Salix spp.).
In the Las Vegas area, the Alpine Tundra association occurs in the Spring Mountains (Mount Charleston) at elevations over about 11,500 feet.
Other peaks in the area may have treeless summits, but they don't have the elevation for Alpine Tundra. |