Noble fir is less tolerant than either western hemlock or amabilis 

 fir, its light requirements being much similar to those of Douglas fir, per- 

 haps being a trifle more tolerant than the latter species. Seedlings will 

 germinate either upon bare mineral soil or duff, although the latter 

 condition appears best. Reproduction takes place only in openings, 

 such as are caused by fire or windfall, seedlings seldom being found in 

 the shade of older stands. Rather moist soil conditions seem to be best 

 for the reseeding of this species. The seed seems to be disseminated 

 by the wind over quite a wide range. 



Noble fir is adapted best, probably, to a type of forest where it is 

 able to maintain a dominant position in the stand, such as when in mixture 

 with Douglas fir and western hemlock, or amabilis fir and hemlock. Since 

 it does not reproduce itself under shade, some system of clear cutting will 

 no doubt be necessary to secure natural reproduction. Throughout the 

 lower altitudinal limit of its range, its management should be akin to that 

 of the associating Douglas fir, while at the higher elevations, where for 

 protective reasons widespread clear cutting cannot be followed, some 

 group system of cutting will have to be followed. Due to its superior qual- 

 ities, noble fir should be favored more than any other species, with the 

 exception of white pine, in the upper limits of the lower slope type and 

 in the lower limits of the upper slope type. 



Growth 



It is probably in direct competition with the rather intolerant species, 

 such as Douglas fir, that noble fir attains its best diameter and height 

 growth. 



Figure 1 illustrates graphically the comparative diameter growths 

 of noble fir, Douglas fir, and western hemlock in a mature stand, the trees 

 of all species averaging about 400 years of age. The results are for 

 only the dominant trees upon the tract of all species. 



Table 1 gives the average rate of diameter growth and height growth 

 of noble fir grown in a mixed stand of Douglas fir and western hemlock 

 at an elevation of from 3,000 to 3,500 feet on the west slope of Larch 

 Mountain in Northern Oregon. 



Table 2 gives the seedling height growth of noble fir grown under 

 average conditions in the same locality as were the trees measured for 

 Table 1. 



Table 3 gives the average number of years required for noble fir 

 seedlings to attain various heights. 



Figure II illustrates graphically the seedling height growth of noble 

 fir, Douglas fir, and western hemlock in Western Washington and Oregon. 

 The growth of noble fir seedlings is slower than that of either Douglas fir 

 or hemlock; to attain breast-height, 4.5 feet above ground, it takes noble 

 fir an average of 1 1 years, open-grown western hemlock 7 years,* and 

 Douglas fir 6 years.** 



*Western Hemlock; Its Forest Characteristics, Properties, and Uses, by 

 E. J. Hanzlik and H. B. Oakleaf. 



**Growth and Management of Doug-las Fir, by T. T. Munger. 



51 



