88 



CURVES 



CURVES FOR THE AVERAGE HEIGHT OF WHITE 

 PINE GROUPS. 



This Plate answers the question : How high is 

 a White Pine forest at a given age ? Thus it 

 appears from the curves that in good soil the 

 average height of a body of Pine timber 100 

 years old is 93 feet. In the preceding 50 years 

 it grew from 64 feet to 93, an increase of 29 

 feet, while in the next 50 years it will grow but 

 17 feet, to reach, at the end of that time, the 

 height of 110. It is easy to see from the shape 

 of the curve that the period of most rapid 

 growth was passed before the end of the first 

 century. 



