Larix lyallii

Larix lyallii, the subalpine larch, or simply alpine larch, is a deciduous, coniferous tree native to northwestern North America. It lives at high altitudes, from 1,500 to 2,900 meters (4,900 to 9,500 ft), in the Rocky Mountains of Idaho, Montana, British Columbia, and Alberta. There is a disjunct population in the Cascade Range of Washington. Subalpine larch is hardy and can survive at low temperatures and on thin rocky soils, often being found near the tree line. It can grow in a variety of soils as long as the soil is moist but well drained. However, it is relatively shade intolerant. David Lyall seems to have discovered the species between 1858 and 1861. John Bernhard Leiberg described it in 1900....read more on Wikipedia.