NOKWAY 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 





Age 





(years). 









(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.] 









Diameter breast-high (inches). 





Diameter breast-high (inches). 



Age 



(years). 





Age 

 (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 





