PNW Native
Ranges from Alaska to California. (3)
Trees grow up to 40 m (110 ft) tall but often have stunted growth habits at higher elevations. Mountain hemlock prefers subalpine environments in the Puget sound region of the PNW, but north of Vancouver Island it grows at lower elevations more frequently. Needles are bluish-green, 1-3 cm long, and surround all sides of the branch to which they are attached and are unflattened like Western hemlocks. Branches are prone to drooping with a slight upturn at tips, bark is deeply ridged and red-brown. Pollen cones and seed cones are distinct from each other in appearance with a blue-hued pollen cone and a purple-hued seed cone that mature into a brown color. Cones are 3-8 cm (1-3.5 in) long. (1)
Mountain hemlock is a crucial species for watershed protection and helps capture snowmelt runoff in association with other plants. (3) Mountain hemlock often forms overstory due to its low shade tolerance. Unlike other conifers, mountain hemlock does not provide adequate rain cover due to upwards-sloping branches. Mountain hemlock is the predominant timberline tree on the wetter side of the Cascades. Due to the incredibly high snowpacks in the subalpine forests where mountain hemlock grows (up to 6 m/ 20 ft), the tree often has a remarkably brief growing season and stunted and warped growth habit. (1) Growing on steep slopes prone to avalanche, there will often be a pronounced bend at the base known as a 'pistol butt' (2). It is susceptible to Indian paint fungus (Echinodontium tinctorium) which also infects Western hemlocks and true firs. (1)
Mountain hemlock also provides general cover and thermal cover during winters and cold nights, summer ranging grounds for large ungulates and mammals including deer, elk, and bears. The rich understory provides deer food during the summers and is important habitat in Alaska and on Vancouver Island, (3) and north of Jordan River on the Island, squirrels will leave hemlock seed caches in Roosevelt elk footprints (1)
Hemlock species served as supernatural magical objects in various Interior Salish stories told by the Nlaka'pamux and Stl’atl’imx tribes. (3) Northern Coast Peoples including the Haida and Ts’msyen would eat the soft inner cambium of western and mountain hemlock during late the late-spring sap runs. The inner cambium would be cooked, eaten raw, stored in cakes for winter, and eaten at grand feasts. The hemlock boughs were also used to construct herring spawn traps. (4)
Mountain hemlock typically grows at too high of an altitude to be harvested widespread as commercial timber but is occasionally sold with western hemlock. When harvested at the lower extent of its range, the moderately strong wood of the hemlock is used for mineshafts, railway construction crates, cabinets, flooring, ceilings, and finishing. (3)
