Tsuga mertensiana aka Mountain Hemlock

Tsuga mertensiana, or mountain hemlock, is an evergreen conifer. It belongs to the pine family. Its range runs from Alaska through British Columbia to California. It also grows in Idaho, Montana, Oregon, Washington, and Nevada. Most stands grow in mountains, though Alaskan trees reach sea level. It thrives where winters last long and summers stay cool.

The tree grows slowly and forms a dense, cone-shaped crown. Its branches spread, with tips that turn upward. The top shoot may lean, and fine twigs may droop. Published heights range from 30–100 feet (9–30.5 m). RHS lists garden height as above 39 feet (12 m). Spread estimates differ, from 10–15 feet (3–4.6 m) at NC State. RHS gives a broader range of 13–26 feet (4–8 m). Exceptional trees reach 175 feet (53.3 m). Flexible trunks bend under snow, then rise after it melts.

Young bark is thin and scaly, with brown to black tones. Older bark turns reddish brown and develops deep cracks. Brown shoots carry needles around their sides, rather than flat rows. The needles are blue-green, grey-green, or silvery, with blunt tips. Each tree bears both pollen cones and seed cones. Young seed cones often look purple and hang from branches. They grow about 0.16–0.26 feet (0.05–0.08 m) long. Their scales curve back as the cones mature. Cones turn brown and open from September to November. Birds and squirrels eat the seeds.

Grow this tree in sun or part shade. Give it moist soil that drains well. NC State favours acid soil; RHS also lists neutral and alkaline soils. Both sources allow several soil textures, including clay, loam, and sand. Cool, moist air helps growth, while hot summers limit success. NC State lists USDA zones 5–8; RHS rates it H7. It suits woodland gardens, screens, and single-tree plantings. Young trees can form hedges with light trimming. Established trees need no routine pruning. Serious diseases are uncommon, but spider mites and woolly adelgid may attack.

PFAF records inner bark as a food used during shortages. Young leaves and shoot tips have served as tea ingredients. It reports no known hazards, rather than proof of complete safety. Indigenous peoples used leaves on burns and bark for several ailments. These records describe past uses, not tested treatments. Bark also supplied dye and tannin for hides. Other recorded uses include resin and scented cones for potpourri.