92 



CURVES 



CUEVES FOR THE VOLUME OF WHITE PINE 

 GROUPS, EXCLUDING BRANCHES. 



If the present volume of a fully stocked acre of 

 White Pine is known, this Plate makes it pos- 

 sible to find its approximate age, or vice versa. 

 It can also be used to ascertain the density of 

 an acre of known volume and age simply by 

 dividing the quantity on the ground by the ap- 

 propriate number found from the curve. By 

 its means the growth of an acre of forest may 

 be predicted, when its age and volume are 

 known, for any desired time. By ascertaining 

 the probable age from the diameter of the av- 

 erage tree through the use of Plate II, it is 

 possible to discover the approximate age, volume 

 per acre, and future increment of a forest of 

 White Pine with no other instrument than a 

 tape measure or a pair of callipers. If the esti- 

 mate desired is a rough one, even these simple 

 measurements may be dispensed with, and a 

 result may be reached by the eye alone. 



If an acre is only half stocked, the chances 

 are that the future growth wiU be more than 

 half that shown by the table, because the trees, 

 as they grow and spread, will fill up the blankSc 

 The density will increase with the age. 



