Tsuga mertensiana (Mountain Hemlock)

Mountain hemlock is a Pacific Northwest native in the truest sense, found from southern Alaska down through the coastal ranges and Cascades into central California, and east into the mountains of Idaho and Montana. In the wild it grows at high elevations where snowpack is heavy and summers stay cool, often forming the picturesque, wind-sculpted trees at timberline. In the garden it translates into a graceful, narrowly conical tree with thin, slightly pendulous branches and needles that radiate in all directions around the stem, giving each branch a distinctive star-shaped or bottle-brush profile. The foliage color is a soft grey-green to silver-white, cooler and more muted than most conifers.

Young cones are worth noticing: they emerge purple, elongated, and pendant, maturing to brown over the season. Mature trees can reach 30 to 100 feet in the wild, though garden specimens in the maritime Pacific Northwest typically grow more slowly and stay at more manageable scales over a human lifetime. The bark is charcoal grey to reddish-brown, becoming deeply furrowed with age.

Mountain hemlock performs best where summers stay relatively cool and the air stays moist.