sitka. spruce: uses, growth, management. 13 



common. Here the trees, though large and tall, are characterized 

 by large buttressed bases, limbiness, and comparatively short clear 

 length. On these moist sites the trees make a noticeably rapid 

 and well-sustained diameter growth, especially from 100 to 200 

 years of age. In this type Sitka spruce occurs also on tidelands 

 and in swamps where there is considerable inundation ; but, although 

 it can stand these conditions, it prefers an excess of soil moisture 

 only with good drainage and in general avoids stagnant sites and 

 acid soils. In contrast with the stands on the bottoms and benches, 

 those in swamps are quite frequently pure, but the trees here are 

 shorter and much more limby. Trees which occur on exposed situa- 

 tions along the coast are small and scrubby and unfit for commercial 

 uses. 



SLOPE TYPE. 



Spruce stands of the slope type are found on the moist but well- 

 drained hills which border the lowlands and which afford all ad- 

 vantages for excellent growth in their rounded ridges and gentle 

 slopes of deep, rich soil. It is not only in the upland country that 

 this type occurs; similar conditions exist on the rolling, sandy land 

 along the coast. The trees on such sites are fine specimens, large and 

 tall, with long, clear length ; and, in contrast with those of the bot- 

 tomland type they seldom develop buttressed bases. (PI. XL) The 

 wood is characteristically fine-grained, and this fact is frequently 

 mentioned by lumbermen as a means of distinguishing between trees 

 of the two types. Spruce in these stands is more often pure than in 

 mixture, and this is especially true on the sandy lands which border 

 the ocean. (PI. XII.) 



COMPOSITION AND VOLUME OF STAND. 



Pure stands of Sitka spruce are usually not extensive but are apt 

 to be limited to patches of a few acres in contrast with Douglas fir, 

 which occurs pure over great areas. Larger pure forests of spruce 

 are found occasionally, however, 40 or more acres in size in Oregon, 

 Washington, and British Columbia, and even 100 acres in Alaska; 

 but this is the exception rather than the rule. 



When Sitka spruce grows in mixture with other species, the most 

 common associate is western hemlock, and large areas of these two 

 species are found in Alaska and in the States as well. Sitka spruce 

 is also associated with Douglas fir, western red cedar, lowland white 

 fir, silver fir. and Pacific yew throughout the range, with Port Orford 

 cedar and redwood only in southern Oregon and California, and 

 with Alaska cedar and mountain hemlock on the upper slopes in 

 British Columbia and Alaska. In the valley bottoms it occurs with 

 such hardwoods as hroadleaf maple, black Cottonwood, and red alder. 

 (PI. X.; 



