Tsuga heterophylla
Western hemlock is an attractive, large canopy tree with graceful, evergreen foliage and a distinctive, drooping leader tip. In May and June, it prolifically grows papery, light brown male and female cones. Male cones are exceptionally small, usually less than ¼”, while females are up to 1” and egg-shaped. Female cones release their seeds in fall, much to the delight of countless species of birds and mammals. The feathery bows also provide excellent cover for wildlife.
- Plant type/canopy layer: evergreen perennial large tree
- Size at maturity: 50’ - 200' tall, trunk grows incrementally over decades until eventually reaching 25’ - 40' wide when it’s 1000 years old (literally!)
- Light requirements: full shade, part sun/part shade
- Moisture requirements: dry to moist soil (prefers moist)
- Bloom time: cones develop in May - June (then mature throughout summer and disperse seed in September/October)
- Growth rate/ease: slow growing, moderately easy to grow
- Wildlife support: seeds are an important food source for chickadees, siskins and crossbills; bark is eaten by native squirrels, porcupines and other mammals; foliage and twigs are eaten by deer and elk; overall plant is a caterpillar host plant and larval food source for around 50 species of native moths and butterflies, supports countless species of beneficial and pest-eating insects, and is a favorite nesting tree for many birds
- Native habitat/range: commonly found in moist, deep forests, at elevations below 3000’, from the west Cascades to the coast, from northern California to southwestern Alaska, as well as the Rocky Mountains of Canada, Montana and Idaho. Portland Plant List - yes.
- Special features & uses: evergreen; wildlife favorite; landscape uses include woodland gardens, erosion control and screens; the inner cambium is edible in winter as a survival food and branch tips can also be used to flavor meat and stave off starvation; medicinally, the needles can be chewed and used for burns, a decoction of pounded bark has been used to treat tuberculosis, an infusion of bark used to treat hemorrhage, and pitch can be used to prevent chapping and sunburn and to heal abrasions; other human uses include using bows as temporary shelters and to wrap/cover food in earthen ovens, making the bark into a brown dye for fishing nets and to smoke hides. The wood makes excellent firewood and building material for tools, masks, dishware, and utensils. Today, western hemlock continues to be used for timber and paper.
Gardening with Western Hemlock: This slow-growing and long lived giant typically sprouts up, in the shade of earlier succession species, often on nurse logs or other loamy soils that are moist and rich in humus. So, when you happen upon them in the forest, it’s usually a sign that you’re in a relatively ancient and healthy part of the forest. Bringing this tree into a habitat garden requires moist, well-drained soils rich in organic matter. It will grow slowly in full shade, and more quickly with a little sunshine. When it’s given the right conditions, and the space and time to thrive, it can easily become one of the most cherished trees for humans and wildlife alike.
Photo Credit 1: "Tsuga heterophylla (Western Hemlock)" by S. Rae is licensed under CC BY 2.0
Photo Credit 2: "Tsuga heterophylla" by gertjanvannoord is licensed under CC BY-ND 2.0
Photo Credit 3: "Hemlock (Tsuga heterophylla)" by Holy Outlaw is licensed under CC BY-ND 2.0