16 



calipers described above. It is always advisable to note the average 

 diameter of two measurements taken at a right angle. 



MEASUREMENT OF VOLUME. 



The volume of a felled tree may be determined with more accuracy 

 than that of a standing tree, for the tree on the ground may be 

 measured in parts and the volume of each x)art determined separately. 

 While the tree, taken as a whole, does not closely resemble any of the 

 known geometrical forms, the portions of the tree, especially when they 

 are small, may be compared to some of the known forms with less 

 hesitation. Of the various methods which may be emi)loy('d in deter- 

 mining the volume of a felled tree, the following are recommended: 



(1) When great accuracy is required and the volume of the stump is 

 included.— Biyide the tree into sections, each 4 feet in length, and 

 caliper at right angles at each section, noting the average of the two 

 diameters, including that of the butt. Find in the table the areas 

 corresponding to the diameters noted and add all together. Multiply 

 the sum of the areas by 4 feet and the product will be the total volume 

 of the tree, if the last measurement with the calipers was taken at 2 

 eet from the top. If the last measurement with the calipers was taken 



Fig. 9. — Determining the volume of a felled tree. 



at a greater distance from the top, the volume of the top part must yet 

 be added. The volume of the leader, or top, equals one-third the prod- 

 uct of the basal area by its length. The base of the leader is taken 

 at 2 feet from tbe last point of measurement with the calipers. The 

 diameter of tbe leader is measured and the corresponding basal area 

 found in the area table. Example: Let the average diameter of the 

 butt be 7.0 inches (fig. 9), and the average diameters calipered from 

 butt for every 4 feet be, consecutively, 5.9, d.o^ 5.1, 4.9, 4.3, 3.5, 2.5, 1.7, 

 and 0.8 inches. The last measurement with the calipers was taken at 

 2 feet from the top. In the area tables we find : 





Location. 



Diame- 

 ters. 



Areas. 



Butt • 



Inches. 

 7.6 

 5.9 

 5.5 

 5.1 

 4.9 

 4.;i 



3.5 



2.5 

 1.7 



0.8 



Sq.ft. 

 315 



4 feet from butt. ...... .... 



. 190 



8 I'eet from butt , . 



.165 



12 feet from butt. . . 



.142 





.131 



20 feet from butt 



.101 



24 feet from butt 



< .067 



i 1.111 



.034 



28 feet from butt . 





.016 



36 feet from bu It - - 



.003 











1.164 



