RATE OF INCREASE. 59 



RATE OF INCREASE IN TIMBER. 



The rate of increase on timber trees varies according- 'to 

 the kind and age of the trees and the conditions under which 

 they are growing Most of the pine trees cut for log timber in 

 this state have been upwards of 100 years old and some of the 

 White and Norway pine that has been cut was over 300 years 

 old. Perhaps the largest White Pine ever cat in this state 

 was scaled by H. B. Ay res. The tree was 253 years old, 

 measured 48 inches in diameter on the stump and yielded 4050 

 feet board measure of log- timber. The most rapidly grown 

 trees recorded in this state were: Norway Pine 100 years old, 

 30 inches on the stump yielding 1050 feet board measure; 

 White Pine, 106 years old, 27 inches on the stump, yielding 

 1050 feet board measure, and White Pine 108 years old, 32 

 inches on the stump, yielding 1450 feet board measure. The 

 largest recorded acre yield of White Pine in Minnesota was 

 near Carlton. The full yield of this acre was 111,050 feet 

 board measure and after deducting for rot and crooks 94,264 

 feet of sound timber remained. The average yield of White 

 Pine is much below this and large areas have been cut that 

 did not -yield over 10,000 feet board measure per acre but 

 much of this has been cut too young for best results. 



Marketable White and Norway Pine may be grown in 

 about 30 years under the best conditions in this section and 

 at this age will probably be about eight inches in diameter 

 and 40 feet high. But such trees are then growing very fast 

 and as the approximate increase in volume of the tree is as 

 the square of the proportionate increase in diameter and the 

 waste in working greatly decreases with the size of the trees, 

 the cutting of them at such an early age would be at a loss of 

 future profits. Such trees have very little, if any, heartwood 

 and yet this kind of timber is being grown and marketed in 

 many of the eastern states. In fact there is very little heart 

 to any of the pine now cut in the New England states as it is 

 practically all young second growth, and is generally mar- 

 keted about as soon as it attains sufficient size to be salable 

 without regard to the fact that it is then making its most 

 rapid growth. 



From careful observation, the Experiment Station of the 



