Trees to 50m; trunk to 2m diam., usually (when forest grown) branch-free over most of height; crown short, conic. Bark reddish brown, scaly, with deep furrows between flat, flaky, cinnamon-colored plates. Branches horizontal, occasionally drooping in lower crown of open-grown trees; twigs orange-brown, initially pubescent, becoming glabrous or very sparsely pubescent during first year. Buds dark brown, generally puberulent, scale margins erose. Leaves of short shoots 2--5cm × 0.65--0.80mm, 0.4--0.6mm thick, keeled abaxially, with shallow convex midrib adaxially, pale green; resin canals 20--50 µm from margins, each surrounded by 5--7 epithelial cells. Seed cones 2--3 × 1.3--1.6cm, on curved stalks 2.5--4.5 ´ 3.5--5mm; scales 45--55, margins entire, adaxial surface pubescent; bracts tipped by awn to 3mm, exceeding scales by ca. 4mm. Pollen 71--84µm diam. Seeds reddish brown, body 3mm, wing 6mm. 2 n =24.

Mountain valleys and lower slopes; 500--1600m; B.C.; Idaho, Mont., Oreg., Wash.

Western larch, when forest grown, is usually branch-free over most of its height. This is one of the most valuable timber-producing species in western North America. Its wood is made into framing, railway ties, pilings, exterior and interior finishing work, and pulp. In some localities it is the preferred firewood.