APPKNDIX. 



TABLES OF MEASUREMENTS. 



The following tables record the detail investigations, measurements, and tabulations which 

 have served as a basis for the discussion of the growth of the White Tine. The measurements 

 in the field were made by Mr. Austin Gary, of Bangor, Me., and by Mr. A. K. Mlodziansky, of 

 the Division of Forestry. Mr. Mlodziansky has also executed the laborious calculations, and is 

 responsible for their accuracy. 



The methods employed in this investigation have been described in general in Bulletin No. 20, 

 "Measuring the forest crop," of the Division of Forestry. They are in the main similar to those 

 practiced by European foresters, with some minor and one important modification, which latter 

 Mr. Mlodziansky has developed during the course of his work in collating the data. This modifi- 

 cation, which refers to the analyzing of trees for ascertaining the rate of growth, consists in 

 grouping by age classes, and instead of analyzing each single-measured tree, as is usually done 

 in European practice, averages the data of measurement from a number of trees grouped and 

 then analyzes the growth of the average tree thus constructed of each age class or group. In 

 this way the work of collating is very considerably reduced and the measurements of a very much 

 larger number of trees can be expeditiously utilized for average statement. It is needful, 

 however, in order to be quite satisfactory, that the classification or grouping of trees be made 

 in the woods while measuring, a task which requires considerable judgment. When the classi- 

 fication is so done in the woods, the mechanical work is further simplified by entering the 

 measurements for each group in sets, the measurements of cross sections taken at the same height 

 being entered on the same sheet for all trees of the group, when the averaging of the measurements 

 can at once be performed on the same sheets. 



The forms used in the investigation are also appended, and will serve to further elucidate the 

 methods pursued. 



Since it was not expedient to fell trees specially for these measurements, it was not always 

 possible to secure all measurements in the most desirable form; for instance, the desirable meas- 

 urement and correlation to age of diameters at breast height, and at short intervals of the height, 

 could not be obtained, because the work was performed on trees cut in regular lumbering opera- 

 tions; hence, the data had to be manipulated and interpolations used so as to secure satisfactory 

 approximations for the periodic growth. The number of trees analyzed (some 700) is so large 

 that any deficiency of method may be considered as neutralized. 



TABLES OP CUBIC AND BOARD CONTENTS OP "WHITE PINE. 



The tables of cubic and board contents of White Pine are based upon the measurements of 

 pine taken for analysis from the various sites described in the tabulations of acre yields. 



The stem of each individual tree was calipered at intervals of 4 or 8 feet, and the volumes of 

 the portions between two successive diameter measurements were calculated separately, considering 

 them as frustrums of cones. From the volumes of stems of similar height and diameter, breast 

 high, the average volume was noted. The volumes of stems of missing dimensions was calculated 

 by employing the corresponding factors of shape. The factor of shape is determined by dividing 

 the volume of a tree by that of a cylinder of the same height and diameter, breast high ; it shows 

 the taper of the stem and is usually expressed in decimals, thus representing arithmetically the 

 form of the stem. For determining the volume of a tree by means of the factor of shape, it is 

 necessary only to measure the diameter and height of the tree, find the volume of a cylinder of the 

 corresponding height and diameter, and multiply that volume by the factor of shape. 



The lumber of stems in board feet was determined by employing Scribner's rule. 



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