Alpine TundraAt high elevations a very short growing season in combination with frequently strong winds and heavy snowfall (annual precipitation of 40 inches) make an environment quite hostile to plant growth. Here specially-adapted tundra species grow in the harsh climate by forming ground-hugging plants which can survive by avoiding the wind and absorbing heat from the ground. Their compact form also retains any available heat.
In Arizona one can find this community only on the uppermost slopes of Mt. Agassiz and Mt. Humphreys atop the San Francisco Peaks just north of Flagstaff. Of over 80 species of plants found in this zone on the peaks, almost half can be found in polar regions near the Arctic and on high summits north into Canada. A rare plant, the San Francisco Peaks groundsel, has only been found on the peaks and part of the mountains has been closed to travel to protect this rare plant. Geographically isolated areas such as the peaks often have quite distinct species as the area serves as an "island" where species develop in a unique environment. The nearest alpine areas are in southern Utah and southwestern Colorado, too far from the the San Francisco Peaks for successful migration of many species.
Other Biotic Communities Biogeographic Regions