Western hemlock (Tsuga heterophylla) is the state tree of Washington, and the largest species of hemlock, growing up to 200′ tall with a trunk diameter of up to 4′. It makes a beautiful addition to any property where it has room to grow.
Western hemlocks grow into a narrow, upright, somewhat ragged cone as they grow, with very top of the tree typically drooping over just a little bit. The needles are short and flat, averaging less than 1″ long. The small round cones dangle from the branches and have long, thin, flexible scales. The bark is thin, brown, and furrowed in texture.
This tree is an important source of food for many birds and mammals. Yellow-bellied sapsuckers nest in the tree’s cavities, and barred owls prefer dense stands of Western hemlock. Flying squirrels and other small mammals nest in hemlocks, and many animals browse the inner bark and young needles and take shelter in the dense foliage.
Western hemlock is a very shade-tolerant tree, with young plants able to grow under a closed canopy of fast-growing, shade-intolerant conifers such as Douglas-fir. Disturbances like fire or logging open up sunny areas where new generations of Douglas-fir and other sun-loving seedlings can survive, but without that disturbance, hemlocks end up dominating the canopy…and Western hemlocks can live up to 1200 years old! If you are in a forest made up of mostly large hemlocks, you know that forest has been undisturbed for a very long time.
