418 



JOURNAL OP FORESTRY 



produced by the more exact method. The values for b, as read from 

 the curve, are given in the column headed b in Table 2. 



Table 2 



D. b. h. 



No. of 

 trees. 



Total 

 length. 



Total 

 scale. 



Total 

 volume. 



12. 



13- 

 14. 



15- 

 16. 



17- 

 18. 

 19. 

 20. 

 21. 

 22. 



23- 

 24. 



25- 



26. 

 27. 

 28. 

 29. 

 30. 



31- 



32. 

 33- 

 34. 

 35- 

 36. 



30 

 34 

 58 

 56 

 S6 

 39 

 39 

 30 

 29 

 30 

 30 

 30 

 30 

 30 

 30 

 30 

 30 

 29 

 30 

 30 

 30 

 30 

 17 

 20 

 18 



586 



804 



1,781 



2,077 

 2,278 

 1,898 

 2,256 



1,886 

 2,083 

 2,227 

 2.542 

 2,839 

 3,152 

 3,373 

 4,111 



4465 

 4,722 

 5,034 

 5,398 

 5,957 

 6,165 

 6,643 

 4,181 

 4,757 

 4717 



Average value for column P 3-213 



3-456 

 3.102 



3.381 



3-300 

 3.100 

 276 

 127 



135 

 080 

 912 

 2.964 

 2.958 

 2.950 

 2.880 

 3-348 

 3-339 

 3.392 

 3-276 

 3-250 

 3-300 

 3-417 

 3-468 

 3-604 



3-234 

 3.128 



2.6 

 3-0 

 3-5 

 4.0 



4-5 



5-0 



5-5 



6.0 



6.6 



7-2 



8.0 



8.7 



9.6 



10.5 



11-5 



12.6 



13-8 



15-1 

 16.4 

 17.8 

 19. 1 

 20.4 

 21.4 

 22.2 

 22.7 



The number of trees of each diameter class, upon which the computations are 

 based, is given in the second column; the total merchantable length of the trees 

 in feet, in the third column ; the total scale by the Scribner Decimal C rule in 

 the fourth column ; and the total volume computed to the nearest whole cubic 

 foot in the fifth column. Column F gives the merchantable form factor for each 

 diameter, which is obtained by dividing the total volume by the volume of a 

 cylinder having the same diameter (column i) and the same total length (column 

 3). Column R shows the ratio of board feet to cubic feet for each diameter class, 

 obtained by dividing the total scale (column 4) by the total volume (column 5). 

 Column P gives for each diameter the product of F and R, and column b gives 

 the board-foot form factor, as read from the curve (see Figure i) and explained 

 in the text. In all computations the decimal 0.785 was used as one-fourth of ir. 



Having obtained the values for b, volume tables based on d. b. h. and 

 merchantable length (log-lengths, etc.) can be readily constructed by 

 using the equation Bf = & X L. For the most precise estimating possi- 

 ble, a table of merchantable lengths in two-foot classes could be made. 

 The values obtained may be rounded to the nearest five or ten board 

 feet. 



