68 



AMERICAN FORESTRY 



DOUGLAS FIR BARK 



On old trees the bark is dark brown outside and clear red-brown when 

 cut into It is deeply furrowed, and has heavy, irregular ridges. 

 Near the base the bark may be from five to ten inches thick, and on 

 very old trees as much as two feet thick. 



though in the Rocky Mountains it may assume a blue- 

 green shade. The leaves remain on the trees from 5 to 

 8 years, and sometimes 11 years, before they fall. 



It makes the finest appearance in the months of June 

 and July. The rich brown buds with which its sprays 

 are tipped swell and break about this time, revealing the 

 young leaves, which at first are bright yellow, making the 

 tree appear as if covered with gay blossoms; while the 

 pcndulus bracted cones with their shell-like scales are a 

 constant adornment. 



The young trees are mostly gathered into beautiful 

 family groups, each sapling exquisitely symmetrical. 

 The primary branches are whorled regularly around an 

 axis, generally in fives, while each is draped with long, 

 feathery sprays, that descend in curves as free and as 

 finely drawn as those of falling water. 



The buds of Doulas fir enable the observer to tell this 

 tree from all other evergreens except the closely re- 

 lated big-cone spruce. They are sharp pointed and coni- 

 cal, with bright red-brown scales. The buds at the ends 

 of the twigs arc about one-fourth inch long and twice 

 the size of the buds on the sides of the branches. 



The flowers are small, scaly bodies, appearing in the 

 early spring. The orange-red pollen-producing flowers 

 are scattered along the branches at the bases of the leaves. 

 The seed-producing flowers are reddish or rose-colored, 

 growing near the tips of the twigs. Usually they are 

 located in another part of the tree from the pollen- 



producing flowers. The latter fall from the tree after 

 the pollen is shed. The seed-producing flowers develop 

 into cones that droop gracefully from the branches. The 

 cones vary from one and a half to four and a half inches 

 in length and are composed of interlapping scales. Each 

 of the six or seven central scales bears two small, tri- 

 angular winged seeds. 



Douglas fir is easily distinguished from all other 

 native cone-bearing trees by the feathered appearance of 

 the cones. This peculiar feature is due to flexible, tri- 

 dent-shaped bracts that extend conspicuously about one- 

 half inch beyond the cone scales. The nearest relative 

 of Douglas fir, the big-cone spruce, has larger cones and 

 the bracts do not extend much beyond the scales. The 

 Pacific Coast form of Douglas fir has a longer and more 

 cylindrical cone than the mountain form, and the feath- 

 ering is less noticeable because the bracts lie close to the 

 scales instead of protruding at a wide angle, as in the 

 mountain form. 



Nature has provided Douglas fir with highly effective 

 methods for scattering its seeds ; as a result, it takes pos- 

 session of burned forest areas very rapidly. The bare 

 mineral soil which is exposed after a fire has swept 

 through the forest is especially favorable for the germi- 

 nation of the seeds. Trees may begin to bear cones as 

 early as twelve years of age; very old trees produce lit- 

 tle or no seed. Vigorous trees produce a fair crop of 

 cones every year and very large crops every three to 

 five years. 



The color of the wood is light red or yellow, with a 

 narrow band of nearly white sapwood. The wood is 

 heavy, hard and strong, but usually is coarse grained and 

 difficult to work. Each year's growth is plainly marked 

 by a band of light-colored wood formed early in the 

 season which grades into a band of dark-colored, flinty 

 summer wood. Owing to the prominence of the rings, 

 the lumber occasionally may be mistaken for yellow pine 

 or larch. 



The heartwood of Douglas fir is durable in contact with 

 the soil. A fallen fir log in a Washington forest was 

 found to be perfectly sound two inches beneath the sur- 

 face, although a cedar tree 78 years old was growing 

 on it. It is one of the woods extensively used for creosot- 

 ing for structural and bridge timbers and railroad ties. 

 Douglas fir grows under many different conditions of 

 soil and climate. For rapid growth it requires deep, well- 

 drained loam soils and abundant rainfall. It grows 

 from sea level where the rainfall exceeds 100 inches to 

 nearly 11,000 feet altitude and 15 inches of precipita- 

 tion, in the southern part of its range. It develops a 

 wide-spreading and deep root system in deep loam soils. 

 On poorly drained land and shallow soils the root sys- 

 tem is flat and spreading, while on rocky or sandy soils 

 more or less of a tap-root is developed. 



The scientific name for Douglas fir means "false hem- 

 lock." It does not partake closely of the character of the 

 hemlocks, which are noted as being our most shade- 

 enduring species; Douglas fir will live under moderate 

 shade, but will not thrive in dense shade. Its require- 

 ments in this respect vary with soil and moisture condi- 



