Subalpine Larch

(Larix lyallii)

Color Photograph: © by and courtesy of Stephen J. Baskouf

Color Photograph: © by and courtesy of Walter Siegmund

Subalpine Larch (Larix lyallii)

Identifying Characters: The clustered needles of the larches and the spiny appearance of the cones will separate this species from all others except Western Larch.

Similar Species: The cones of Western Larch are 1 to 1.5 inches in length. In contrast the cones of Subalpine Larch are longer (1.5 to 2 inches. Subalpine Larch normally occurs near tree line, but Western Larch is found at lower elevations. The needles of Subalpine Larch are 4 angled to cylindrical in cross-section, but those of Western Larch are 3-sided.

Measurements: Subalpine Larch typically reaches heights between 30 to 50 feet and 1 to 2 feet in diameter. The shape of the tree is not as conical as that of Western Larch.

Cones: Cones 1.5 to 2 inches long, ovoid and slightly cylindrical, located upright on the twigs; cone scales red-purple and exceeded in length by the three-toothed cone brachts; cones appearing spiny.

Needles: Needles deciduous, pale blue-green turning yellow in the fall before being shed; needles 1 to 1.25 inches long, arranged in clusters on small, side twigs; needles 4 sided to cylindrical in cross-section.

Bark: Dark red-brown, thin, becoming furrowed into irregular scaly plates.

Native Range: Subalpine Larch occupies a remote and rigorous environment, growing in and near the timberline on high mountains of the inland Pacific Northwest. Although Subalpine Larch is found in both the Rocky Mountains and the Cascades, the two distributions are separated at their closest points by 200 km (125 mi) in southern British Columbia. This and smaller gaps in the species' distribution generally coincide with an absence of suitable high mountain habitat.

In the Rocky Mountains Subalpine Larch extends from the Salmon River Mountains of central Idaho, latitude 45° 28' N. northward to latitude 51° 36' N. several kilometers past Lake Louise in Banff National Park, AB. Within this distribution, Subalpine Larch is common in the highest areas of the Bitterroot, Anaconda-Pintler, Whitefish, and Cabinet Ranges of western Montana. It is also found in lesser amounts atop numerous other ranges and peaks in western Montana and northern Idaho. In British Columbia and Alberta, Alpine Larch is common along the Continental Divide and adjacent ranges, and in the Purcell and southern Selkirk Ranges.

In the Cascade Range Subalpine Larch is found principally east of the Cascade Divide and extends from the Wenatchee Mountains (47° 25' N.) in central Washington northward to about 21 km (13 mi) inside British Columbia (49° 12' N.). Within this limited distribution covering a north-south distance of only 193 km (120 mi), Subalpine Larch is locally abundant in the Wenatchee, Chelan, and Okanogan ranges. (Silvics of North America. 1990. Agriculture Handbook 654.)

Habitat: Subalpine Larch occurs at timber line on thin, rocky soils. Typically associated with Engelmann Spruce and Subalpine Fir.