Western Hemlock
Known for its durable timber, the western hemlock is a species of large conifers found in the western coastal regions of North America. It is the dominant climax species in the forests west of the Pacific Coast Ranges.
Scientific Classification
Kingdom | Plantae |
Division | Pinophyta |
Class | Pinopsida |
Order | Pinales |
Family | Pinaceae |
Genus | Tsuga |
Scientific Name | Tsuga heterophylla |
Quick Information
Other Names | Western Hemlock-Spruce, Pacific Hemlock, Coast Hemlock, West Coast Hemlock |
Size | Height: 50 to 70 m (165 to 230 ft); occasionally grows up to 83.34 m (273.42 ft) Trunk diameter: Up to 2.7 m (9 ft) |
Identification | Leaves (Needles): Short-stalked, finely toothed, flat, 5-20 mm long, irregularly spare Cones: Ovoid, short-stalked, thin papery scales; greenish to reddish-purple turning brown with age Bark: Smooth and reddish-brown when young; becomes darker, ridged and scaly upon maturity |
Shape at Maturity | Narrow crown, down-sweeping branches, drooping lead shoot |
Tree Type | Evergreen |
Distribution/Range | Alaska, California, Montana, Idaho, Oregon, Washington (United States); Alberta, British Columbia (Canada) |
Hardiness Zones | 6 |
Growth Rate | Initially slow; once established, seedlings can grow at a rate of more than 24 inches per year |
Lifespan | 400-500 years |
Growing Conditions | Winter Conditions: Average winter temperatures range from -10.9° to 8.5° C Summer Conditions: Average summer temperatures range from 11° to 20° C Rain: 560-1730 mm per year (Rocky Mountains); 380-6650 mm per year (Alaska, British Columbia) Sunlight: Tolerates shade Soil Requirements: Moist, well-drained, acidic, light sandy, medium loamy |
Diseases and Pests | Dwarf mistletoe, Heterobasidionannosum, Phellinusweiri, Echinodontiumtinctorium, Rhizina undulate (root rot), Sirococcus strobilinus; western larch borer, weevil, and hemlock looper cause damage |
Flowering/Fruiting | Floweringbegins in April, continues until May-June; cones mature 4-5 months after pollination, seeds ripen in September |
Breeding System | Monoecious |
Seed Production | Good cone crops occur after 25-30 years of age |
Seedling Development | Germination is epigeal; seedlings are sensitive to cold, heat, drought, and wind |
Wildlife Value | Black-tailed deer and Roosevelt elk feed on the leaves and twigs; black bear cut through the bark of pole-size trees; mountain beaver, brush rabbit, and snowshoe hare clip off branches and stems of seedlings |
Uses | For wood pulp, poles, railway ties, pilings, construction lumber; as specimen trees, hedging plants, and bonsai |
IUCN Conservation Status | Least Concern |
Interesting Facts
- In 1947, western hemlock was designated as the “Washington State Tree.”
- Native people used hemlock bark as a tanning agent and cleansing solution, owing to its high tannin content.
- Its inner bark was used by the Alaska Indians to produce coarse bread.
References:
Published on January 22nd 2017 by admin under Hemlock.
Article was last reviewed on 5th December 2022.