sitka spruce: uses, growth, management. 11 
The species attains its maximum development in Washington and 
Oregon. The average tree found in the virgin forest has a height of 
about 230 feet and a diameter of 4 feet, measured 15 feet above 
ground. North of the optimum range in British Columbia it grows 
to maximum diameters of 8 to 12 feet and heights of 160 to 180 feet ; 
but ordinarily it is only 3 to 6 feet in diameter. 6 In Alaska, too, its 
average diameter is 3 feet and its height about 150 feet, but single 
trees frequently exceed this. In California it is smaller than farther 
north and becomes only a medium-sized tree. This subject is dis- 
cussed more fully under the heading " Growth." 
LONGEVITY. 
Sitka spruce is a. long-lived tree. Sudworth reports a maximum age 
of 750 years. 7 During the recent study, however, the oldest tree that 
could be found was 586 years of age. It is doubtful whether many 
individuals ever reach an age of over 600 years, and the mean mature 
age is not more than 450 years. 
DISTINGUISHING CHARACTERISTICS. 
An outstanding characteristic of the appearance in the forest of 
Sitka spruce is its bark (PL VII). The thin, stiff, cupped, and 
elliptical dark purple-gray scales 1 or 2 inches in diameter make 
this species easily distinguishable from its associates in the stand. 
Little protection is afforded to the living tissues, however, by the 
bark, which is only one-half to 1 inch thick. 
The needles are also of distinctive appearance. In spring the yel- 
lowish green color of new needles in sprays that bend downward 
limply at the ends of the branches stands out in contrast with the 
dark bluish green of the older needles ; and although the young leaves 
are soft and velvety to the touch, during the remainder of their 5 to 
6 year existence they are stiff and stand out straight in all directions 
around the twig, each needle tip being keenly pointed and quite 
bristly to the touch. The leaves are somewhat flattened, only indis- 
tinctly four-angled, and about 1 inch long. 
The cones, too, exhibit peculiarities by which this species may be 
identified. They have an average length of 3 inches, are light 
brown in color, elliptical in shape, and hang down conspicuously 
from the upper branches. The cone scales are thin and papery, 
with irregular margins but slightly pointed in general outline, and 
are firmly attached to the central stalk of the cone. Maturity is 
reached at the end of one year's development; soon thereafter the 
scales open and release the small dark brown seeds with their large 
thin wings adhering to them. Most of the cones drop from the 
• " Forests of British Columbia," by EL N. Whitford and R. D. Craig, p. 199, 1918. 
* " Forest Trees of the Pacific Slope," G. B. Sudworth, p. 83, 1908. 
