It lives at high altitudes, from 1,500 to 2,900 meters (4,900 to 9,500 ft),[3] in the Rocky Mountains of Idaho, Montana, British Columbia, and Alberta.

Subalpine larch is hardy and can survive at low temperatures and on thin rocky soils, often being found near the tree line.

[3] Larix lyallii is a small tree, growing from 10 to 25 meters (33 to 82 ft) tall and shorter at higher elevations.

The seed cones, 2.5 to 4 centimeters (1 to 1+1⁄2 in) long, are red-purple when young but become dark brown with age.

There is record of a specimen in Kananaskis, Alberta, which has been understood to be about 2,000 years old, the oldest tree in Canada.