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Alphabetical List of Tree Common Names Alphabetical List of Tree Scientific Names Identification Key Mystery Tree

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mountain hemlock (Tsuga mertensiana)

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  • Needles: Between 1/2" and 1" long; blunt; green to blue-green in color; uniform color on all sides of a single needle; star-like appearance on short shoots.

  • Fruit: Woody cones 1-3" long; thin, rounded scales.

  • Twigs: Moderately stout; many short shoots; terminal branch tips have a natural bend; have small, rounded pegs (leaf scars) on twigs with 1 needle arising from each peg.

  • Distribution: Grow on exposed ridges and slopes in the Pacific Northwest, and in the mountains of British Columbia and Idaho. Found at altitudes up to 11,000 ft. (3300 m).


western hemlock (Tsuga heterophylla)

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  • Needles: Short (under 3/4" long) and blunt; two distinctly different sizes; green above and white underneath each needle; most needles appear to arise from the sides of the twigs.

  • Fruit: Small, woody cones (about 1"); egg-shaped; thin, smooth scales.

  • Twigs: Thin and droopy; have small, rounded pegs (leaf scars) on twigs with 1 needle arising from each peg.

  • Distribution: Primarily found in the coastal regions of the Pacific Northwest. Occurs from sea level to 7400 ft. (2250 m).


For more information about these species, see "Trees to Know in Oregon".


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