Alaska-cedar also called yellow cedar (which disputed genus has been variously Chamaecyparis, Cupressus, and Xanthocyparis), extends from coastal mountains in Alaska to a very few locations in the Siskiyou Mountains in California. It can grow to 130 feet in the northern part of its range but in the Siskiyou Wilderness, in Six Rivers National Forest, at the extreme southern range of the species, trees were not half that tall.
Alaska-cedar thrives in coastal rainforests, and recent research into large-scale die-offs indicates that Alaska cedar depends on heavy coastal snowpack for insulation. Thinner snowpacks due to climate change have allowed increased damage from freezing.
Alaska-cedar has been considered one of the finest timber trees in the world. The wood has been used for flooring, interior finish, and shipbuilding, and was used by many Northwest Coast peoples for bows, paddles, dishes, and many other items.
Alaska-cedar is long-lived. One, on Vancouver Island, now deceased, had 1,636 annual rings (Lanner). A specimen in BC is 1,834 years old. Gymnosperm Database
A notable hybrid with Monterey cypress (Cupressus macrocarpa) is Leyland cypress, (Cupressus x leylandii), popular for rapid growth and slender shape, but possibly less desirable now now due to its susceptibility to drought. Leyland cypress was developed in Britain around 100 years ago for suburban hedges.
A note about hyphenated names: I've followed a common convention of using the hyphen, Alaska-cedar, since it is not a true cedar (genus Cedrus). Other writers omit the hyphen.
Scale-like needles are small, and branchlets are pendulous. Seed cones are spherical, about one third inch in diameter, take two years to mature, and have spikes or horns at the end of each scale, like a large juniper "berry" with spikes.
Photo of Alaska-cedar pollen cones by Ken Denniston, from Northwest Conifers, http://nwconifers.com
Alaska-cedar at Buck Lake, Six Rivers National Forest
These Alaska-cedars comprise a small stand at Devil's Punchbowl, 4840', Six Rivers National Forest. When I first looked closely at the bark, I thought the black coloration was mold or fire damage. Later I learned that it is due to a scale insect. In photo below you can see one stump at the lower left side. I did not pay attention to that, but have since learned that more than a dozen trees were cut—for firewood?!—between 2009 and 2012. Michael Kauffmann has written an excellent blog post about this incident. Check it out here
Alaska-cedar at the Regional Parks Botanic Garden in Tilden Park near Berkeley, California