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Hemlock (Tsuga)

  • Short needles, generally under 1" long.
  • Each needle is borne on a small, raised, rounded peg.
  • Needles of some species are green on top with white bands beneath, while others have uniform color on top and bottom.
  • Some species have needles of 2 distinct sizes, while others have needles of uniform length.
  • Small, woody cones (1-3" long).
  • Trees have distinctive droopy tops and branches.


Hemlocks are noted for short needles and droopy tops and branches. There are only about 10 species of hemlock in the world--mostly in North America, China, and Japan. The Pacific Northwest has two hemlocks: the abundant and commercially important western hemlock and the lesser known mountain hemlock. Even when found growing together, they're easy to tell apart.

mountain hemlock: needles are blue-green on all surfaces, are similar in size, and are uniformly arranged around the twig. Clusters of needles often have a star-like appearance. Cones are cylindrical and are 1 to 3 inches long.

western hemlock: needles are all very short, but have distinctly different sizes on the same twig. They are yellow-green on top, and have two white bands on their undersides. They tend to stick out the sides of the twigs, but also occur on top of the twig. Cones are egg-shaped and about 1 inch long.

species page

For more information on the hemlocks native to the Pacific Northwest, go to the species page or see "Trees to Know in Oregon".

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