The Rocky Mountains subalpine zone is the biotic zone immediately below tree line in the Rocky Mountains of North America. In northern New Mexico, the subalpine zone occupies elevations approximately from 9,000 to 12,000 feet (2,700 to 3,700 m);[1] while in northern Alberta, the subalpine zone extends from 1,350 to 2,300 metres (4,400 to 7,500 ft).[2]
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