24 BULLETIN 680, U. S. DEPARTMENT OE AGRICULTURE. 



trees a few weeks later. One of the simplest means of identifying 

 this tree is by the 3-pointed, tridentlike, thin bracts 38 protruding 

 from among the cone scales. Cones vary in length from 1^ to A.\ 

 inches, but commonly from about 2\ to 3 inches. The seeds 

 (PI. VI, a) are dull russet-brown, with areas of white. Seed-leaves, 

 about three-fourths of an inch long, vary in number from 6 to 7 

 (PL VIII). 



The wood of Douglas fir varies greatly in quality and in the thick- 

 ness of annual rings, which may be very wide, medium wide, or 

 narrow. Wide-ringed wood is usually a distinctly reddish brown, 

 this being the "red fir" of lumbermen. Narrow-ringed wood is 

 usually a clear yellowish brown, the " yellow fir" and " Oregon pine" 

 of lumbermen. The botanical characteristics of trees furnishing 

 these dissimilar qualities of wood are the same, and there is no 

 foundation for the popular belief that the woods come from two 

 different " varieties" or " species" of trees; indeed, the two grades 

 of wood may sometimes be obtained from the same tree, the wide- 

 ringed wood being in the center of the trunk and the narrow-ringed 

 wood in the outside portion. For the first 50 to 100 years or more 

 diameter growth is rapid, giving wide-ringed wood ("red fir"), 

 while the later stages of growth are, as a rule, slower and give narrow- 

 ringed wood ("yellow fir"). The invariable difference in color 

 between these two grades of wood is often attributed to the character 

 of the soil, but this explanation ignores the fact that both grades 

 may come from the same tree. Grades intermediate between these 

 are also common, especially in trees grown outside of the humid 

 northwestern range, from which the bulk of "red" and "yellow" 

 timber is obtained. Both grades are exceedingly important com- 

 mercially, but the narrow-ringed, yellow wood is the more valuable, 

 being extensively used at the present time for the finest sorts of 

 finishing lumber, for which it competes with high-class pine. 

 Douglas fir wood compares closely in weight and texture with 

 western yellow pine, a cubic foot of thoroughly seasoned fir wood 

 weighing about 32 pounds. The yellow-wooded form is much more 

 durable when exposed to the weather or earth than the red-wooded 

 form, the lasting qualities of both grades being rather remarkable 

 when they are used for piling. 39 



38 As a rule, the bracts of the Rocky Mountain form of Douglas fir are strongly reflexed (PI. VII), those 

 of the Pacific slope tree remaining more or less straight (PI. VI). The latter peculiarity is, however, 

 confined wholly to the more western form of this tree. 



39 In a letter to the writer, dated February 12, 1909, Mr. F. H. Conant says that during lumber operations 

 in (sec. 15, T. 21 N., R. 8 E.) west Washington, two sound logs were cut from a large fallen Douglas fir 

 on the top section of which (then decayed) a 240-year-old western hemlock (cut at that time) had grown. 

 The inference that two sound logs were obtained from the fallen Douglas fir after all those years seems 

 scarcely credible. 



