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 Most of the old growth Douglas-fir has been used and the second growth wood is now predominate.
Wide ringed second growth Douglas-fir from the coastal states and material grown in the southern
Rocky Mountain states tends to be lighter in weight and to have lower strength properties.
The heartwood is orange red to red or sometimes yellowish. The resin canals, which are seen as
brownish streaks in the latewood, appear somewhat abundant and detectable. The transition from
earlywood to latewood is abrupt. The heartwood of Douglas-fir may be confused with that of the
southern yellow pines, but resin canals are larger and much more abundant in southern pine. Most
Douglas-fir has a distinctive odor.
3.2.1.2 Western Hemlock. Western hemlock (Tsugu heterophylla) grows along
the Pacific coast from Alaska to the San Francisco Bay, and as far inland as northern Idaho and
northwestern Montana. The best stands are found in the humid coastal regions of Oregon,
Washington, and Alaska and on the lower slopes of the Cascade Mountains in Washington and
Oregon.
Western hemlock is moderately light in weight, averaging 29 pounds a cubic foot, and moderately
hard, with a specific gravity of 0.45. It is also moderately weak and its shock resistance is fairly
low. Although western hemlock has moderately large shrinkage, it is comparatively easy to season.
The heartwood is low in decay resistance, but the wood is easy to work with tools and it has satisfac-
tory gluing properties.
The heartwood of western hemlock is light reddish-brown and frequently has a purplish cast, espe-
cially in the latewood bands. Transition from earlywood to latewood is gradual and on the end-
grained surfaces there is little color contrast between the two zones. The wood lacks normal resin
canals.
3.2.1.3 White Fir. Commercial white fir includes white fir (Abies concolor),
grand fir (A grandis), Pacific silver fir (A. amabilis), California red fir (A. magnifica), and noble fir
(A. procera). The species grow throughout the Pacific Coast and Rocky Mountain states. The
largest stands of white fir (A. concolor) probably occur in California, but other states contain larger
stands of the other species.
White fir is light in weight, the various species ranging from 26 to 28 pounds per cubic foot. It is
moderately soft, with an average specific gravity of 0.41, moderately weak, moderately low in
shock resistance, moderately stiff, and low in nail-withdrawal resistance. It is difficult to season, a
fact that retarded its use until satisfactory seasoning methods were developed. Also, its decay resis-
tance is low, but gluing properties are satisfactory.
The heartwood is nearly white to pale reddish-brown and the wood lacks normal resin canals. Tran-
sition from earlywood is more abrupt than in western hemlock. Also, more contrast occurs in the
color between earlywood and latewood on the end-grain surfaces than in western hemlock. Wood
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