Upper Treeline and Alpine Tundra - Mountains and Plains: The Ecology of Wyoming Landscapes - page 230

Chapter 14 Upper Treeline
and Alpine Tundra

Found at the highest elevations, with views of the val-
leys below, alpine tundra is the land of the pika, rosy-
finch, wind-swept trees, and small plants with big
flowers. During the last ice Age, the treeline was lower
and tundra extended over a larger area (see chapter 2).
Alpine animals could move easily from one mountain-
top to another. Since then, as the climate has warmed,
the tundra has been invaded by trees. Will the tun-
dra habitat be further diminished to the point where

many of its inhabitants will be unable to survive in the
region? to make predictions, conservation biologists are
thinking broadly about the tundra environment and
the ecology of the plants and animals that live there.
Subalpine forests give way to alpine tundra at eleva-
tions ranging from about 11,480 feet in the Medicine
Bow Mountains, in southern Wyoming, to about 9,840
feet in the Beartooth and Bighorn mountains on the
border with Montana (figs. 14.1 and 14.2) . 1 Slope expo-

Fig. 14.1. Alpine tundra in the
Snowy Range of the Medicine
Bow Mountains. the bedrock
of this glaciated valley is
Medicine Bow quartzite.
elevation 10,825 feet.

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