NORWAY PINE IN THE LAKE STATES. 
19 
Table 8 shows the diameter growth of intermediate trees on situ- 
ations typical of the sandy plains of low agricultural value. 
Table 8. — Minimum, average, and maximum diameter growth of intermediate trees on 
the basis of age, Cass and Itasca Counties, Minn. 
[Based on 760 stump counts.] 
Diameter breast-high 
(inches). 
Diameter breast-high (inches). 
Age 
(years). 
Age 
(years). 
Minimum. 
Average. 
Maximum. 
Minimum. 
Average. 
Maximum. 
10 
0.4 
0.9 
2.3 
110 
6.6 
13.5 
21.7 
20 
.9 
2.7 
6.0 
120 
7.2 
14.2 
22.5 
30 
1.4 
4.6 
9.3 
130 
7.7 
14.9 
23.1 
40 
2.0 
6.3 
12.0 
140 
*' 8.2 
15.5 
23.6 
50 
2.6 
7.8 
14.2 
150 
8.7 " 
16.1 
24.1 
60 
3.3 
9.1 
16.0 
160 
9.1 
16.7 
24.6 
70 
3.9 
10.3 
17.5 
170 
9.5 
17.2 
25.0 
80 
4.6 
11.3 
18.9 
180 
9.9 
17.7 
25.4 
90 
5.3 
12.1 
20.0 
190 
10.3 
18.3 
25.7 
100 
5.9 
12.9 
20.9 
200 
10.7 
18.9 
26.0 
Table 9 shows the growth of suppressed trees. 
Table 9. — Minimum, average, and maximum diameter growth of suppressed trees on 
basis of age, Cass and Itasca Counties, Minn. 
[Based on 164 stumps, 51 to 152 years old.] 
Diametei 
breast-bigh (inches). 
Diameter breast-high (inches). 
Age 
Age 
(years). 
(years). 
Minimum. 
Average. 
Maximum. 
Minimum. 
Average. 
Maximum. 
10 
0.5 
1.3 
90 
5.3 
9.5 
14.8 
20 
0.5 
1.8 
3.9 
100 
6.0 
10.1 
15.5 
30 
1.1 
3.2 
6.4 
110 
6.7 
10.7 
16.1 
40 
1.7 
4.5 
8.7 
120 
7.2 
11.3 
16.8 
50 
2.4 
5.8 
10.6 
130 
7.7 
11.8 
17.4 
60 
3.1 
7.0 
12.0 
140 
8.1 
12.3 
18.0 
70 
3.9 
8.0 
13.1 
150 
8.5 
12.8 
18.6 
80 
4.6 
8.8 
13.9 
The demand of Norway pine for light, which prevents it from 
growing under hardwoods, white pine, or underbrush, is brought out 
in the growth tables. When growing with any other species except 
jack pine it must remain dominant by means of rapid growth or be 
killed by suppression in the course of time. Jack pine has such a 
light crown that in mixture with it Norway pine can survive a period 
of extended suppression and ultimately develop a fair crown growth. 
The better the soil the closer will be the competition between these 
two species. On very poor soils Norway pine in mixture with jack 
pine sometimes lives to an advanced age as mere stunted poles from 
10 to 20 feet high and from 1 to 8 inches in diameter. 
VOLUME GROWTH. 
Growth in volume of Norway pine (Table 10) is derived from tables 
of growth in diameter and height at different ages, used in connection 
