ON THE FORM OF THE BOLE OF THE BA.LSAM FIR. 



Two days leisure on the banks of the Raquette River in the 

 Adirondacks where pulpwood was being cut gave opportunity for 

 measuring the boles of ninety-four Balsam Fir trees. The num- 

 ber is far too small for a satisfactory study, but the results were 

 so suggestive that they are presented here in the hope that some- 

 one who has leisure and opportunity may be inspired to take up 

 the task of determining more accurately the constant for this 

 species. 



The trees measured grew on a sandy loam of somewhat swampy 

 tendencies on the east bank of the Raquette River, Township 23, 

 Franklin County, New York, at an elevation of about 1600 feet. 

 The trees varied in diameter from 6 to 14 inches, and in height 

 from 50 to 76 feet. A majority were approximately 60 years old, 

 while a minority varied from 45 to 160 years. They were almost 

 all quite sound and of thrifty growth. The measurements were 

 taken in the metric sj-stem to facilitate computation, and com- 

 parison with the volumes given in Baur's and Schiffel's volume 

 tables of the Norway Spruce. For the purposes of this note the 

 more important measurements have been translated into feet and 

 inches. The stems were measured sectionwise, the sections being 

 two meters long. The diameter was measured at the center of 

 each section by calipering twice at right angles, the average of 

 the two readings correct to the millimeter being taken. The 

 diameter was similarly measured at ^ and Y2 height. Wherever 

 irregularities were met the diameter was taken above and below 

 the point and the mean taken. The total length of stem was 

 noted, also the length of top above a diameter of 4 inches. 



The accompanying figure represents graphically the form of the 

 stem of two average and two individual trees. The height of the 

 figure vertically representing the tree height of 65 feet. The 

 diameters are represented on a somewhat larger scale horizontally. 

 The line at the center of the figure represents the middle point of 

 the boles. The curved lines representing the outline of the boles 

 terminate at breast-height which was the lowest point measured. 



The heavy full line represents the average form of 14 trees of 

 65 feet in height. The influence of the enlarged base of the bole 

 (root-swelling) is appreciable at the breast-high point, and gives 



