Sltka spruce: uses, growth, management. 
27 
VOLUME. 
The volume growth of Sitka spruce is also rapid and well sus- 
tained. Table 8 indicates the average diameter, height, and volume, 
and the average volume growth that may be expected of dominant 
Sitka spruce trees in the spruce region of Oregon and Washington. 
The figures for diameter, height, and board-foot volume were taken 
from Tables 6, 7, and 11. Those for cubic-foot volume were sup- 
plied from a tree diagram in which the figures for average diameters 
and heights were combined with complete stem analyses of 10 domi- 
nant trees. 
As indicated in this table, the periodic annual volume increment 
of spruce at 100 years exceeds 5 cubic feet, and at 300 years it is 
double .this amount. The periodic annual growth continues greater 
than the mean annual for a long time after 300 years. At 100 years 
of age the volume of the entire stem without bark of dominant Sitka 
spruce trees approaches the high figure of 300 cubic feet, and at 200 
and 300 years it exceeds 1,000 and 2,000 cubic feet respectively. 
Table 8. — Average diameter, height, and volume and average volume groicth of 
dominant Sitka spruce trees in Oregon and Washington. 
Size. 
Volume. 
Annual volume growth. 
Age. 
D. o. b. 
at 15 ft. 
Total 
height. 
Entire 
stem 
without 
bark. 
From 
stump 
height 
to top 
d. i. b. 
of 10 
inches. 
Periodic. 
Mean. 
Periodic. 
Mean. 
Years. 
20 
Indus. 
It 
15.7 
20.5 
24.4 
28.1 
31.5 
34.7 
37.7 
40.6 
43.4 
46.2 
48.8 
51.4 
54.2 
Feet. 
31 
70 
104 
132 
154 
173 
188 
200 
210 
218 
224 
228 
232 
234 
236 
Cu.ft. 
3 
22 
87 
175 
279 
400 
538 
690 
859 
1,036 
1,219 
1,417 
1,617 
1,818 
2,020 
Bd.ft. 
On. ft. 
0.15 
.9 
3.2 
4.4 
5.2 
6.0 
6.9 
7.6 
8.4 
8.8 
9.2 
9.9 
10.0 
10.0 
10.1 
Cu.ft. 
0.15 
.5 
1.4 
2.2 
2.8 
3.3 
3.8 
4.3 
4.8 
5.2 
5. 5 
5.9 
6.2 
6.5 
6.7 
Bd.ft. 
Bd.ft. 
40 
60 
260 
670 
1,230 
1,960 
2,700 
3,690 
4, 640 
5,660 
6,720 
7,800 
8,940 
10, 040 
11,170 
4 
80 
20 
28 
36 
40 
46 
47 
51 
53 
54 
57 
55 
56 
8 
100 
120 
140 
12 
16 
20 
160 
23 
180 
25 
200 
28 
220 
30 
240 
32 
260 
34 
280 
36 
300 
37 
YIELD. 
The yield of Sitka spruce per acre in the virgin forest varies con- 
siderably with its representation as a species in the stand, with the 
density of stocking, and with the quality of site. Although available 
data are not sufficient to furnish yield tables for the wide range 
