22 BULLETIN 13, tT. S. DEPARTMENT OF AGRICULTURE. 
Table 4. — Yield per acre in cubic feet, quality II. 
Aver- 
Diam- 
Num- 
ber of 
trees 
per 
acre. 
Aver- 
Diam- 
Num- 
ber of 
trees 
per 
Age. 
age 
height 
eter 
breast 
Basal 
area 
Total 
Age. 
age 
height 
eter 
breast 
Basal 
area 
Total 
of domi- 
high of 
per 
vield. 
of domi- 
high of 
per 
yield. 
nant 
average 
acre. 
nant 
average 
acre. 
trees. 
tree. 
trees. 
tree. 
Years. 
Feet. 
Inches. 
Sq.ft. 
Cu.fl. 
Years. 
Feet. 
Inches. 
Sq.ft. 
Cu.ft. 
10 
6.0 
1.4 
2,015 
20 
650 
60 
74.5 
10.7 
397 
248 
8,500 
15 
12.0 
2.2 
1,834 
50 
1,150 
65 
79.0 
11.6 
348 
255 
9,200 
20 
19.5 
3.2 
1,626 
90 
1,750 
70 
83.0 
12.4 
311 
261 
9,840 
25 
28.0 
4.] 
1,420 
131 
2,420 
75 
86.5 
13.3 
277 
267 
10,400 
30 
36.5 
5.1 
1,192 
169 
3,250 
80 
90.0 
14.1 
251 
272 
10, 930 
35 
44.5 
6.1 
950 
193 
4,180 
85 
93.0 
14.9 
229 
277 
11,400 
40 
51. 5 
7.1 
760 
209 
5,130 
90 
95.5 
15.7 
210 
282 
11,850 
45 
58.0 
8.0 
633 
221 
6,100 
95 
98.0 
16.4 
195 
286 
12,250 
50 
64.0 
8.9 
537 
232 
7,000 
100 
100.0 
17.1 
1S2 
290 
12,630 
00 
69.5 
9.8 
460 
241 
7,800 
Table 5. — Yield per acre in cubic feet, quality III. 
Aver- 
Diam- 
age 
eter 
Age. 
height 
breast 
of domi- 
high of 
nant 
average 
trees. 
tree. 
Years. 
Feet. 
Inches. 
10 
4.0 
1.0 
15 
9.0 
1.6 
20 
14.5 
2.3 
25 
21.0 
3.1 
30 
28.5 
3.9 
35 
36.0 
4.7 
40 
42.5 
o. 
45 
48.5 
6.3 
50 
54.0 
7.0 
55 
58.0 
7.8 
Num- 
ber of 
trees 
per 
acre. 
2,408 
2,234 
2,060 
1,886 
1,676 
1,400 
1,118 
900 
764 
639 
Basal 
area 
Total 
Age. 
per 
vield. 
acre. 
Sq.ft. 
Cu.ft. 
Years. 
14 
530 
60 
33 
900 
65 
60 
1,350 
70 
98 
1,850 
75 
139 
2,450 
80 
167 
3,100 
85 
1S3 
3,780 
90 
194 
4,500 
95 
204 
5,200 
100 
212 
5,870 
1 
Aver- 
age 
height 
of domi- 
nant 
trees. 
Diam- 
eter 
breast 
high of 
average 
tree. 
Num- 
ber of 
trees 
per 
acre. 
c eet. 
Inches. 
64.0 
8.6 
543 
68.0 
9.4 
465 
71.5 
10.1 
412 
75.0 
10.9 
361 
78.0 
11.7 
318 
81.0 
12.4 
288 
83.0 
13.2 
258 
85.5 
13.8 
239 
87.0 
14.5 
219 
Basal 
area 
Total 
per 
yield. 
acre. 
Sq. ft. 
Cu.ft. 
219 
6,530 
224 
7,160 
229 
7,760 
234 
8,320 
238 
8,820 
242 
9,300 
245 
9,750 
248 
10,150 
251 
10. 530 
Although only fully stocked stands were selected as a basis for the 
tables, the field data were further narrowed by choosing only those 
which came nearest to the average degree of stocking. As a means 
of making the selection the total basal area per acre of the sample 
plots — that is ; the aggregate cross-section area at breast height of all 
the trees, expressed in square feet — were plotted on cross-section paper 
according to age and quality and an average curve drawn through the 
points representing each quality class. All the sample plots in each 
class which deviated from the average by more than 10 per cent were 
considered abnormally stocked. Cubic-foot yields given in the tables 
were computed by means of Table 26, Appendix. 
The lumber yields given in Table 6 are the graphical averages of 
the individual sample plot yields obtained by means of the board-foot 
volume table 24 on page 66, which is based on the actual saw cut. 
All trees over 5 inches breast high were scaled, 
