MEASURING THE FOREST CROP 115 



edge of the fist holding the stick, and the top of the 

 tree over the tip of the stick. Pace the distance from 

 that spot to the foot of the tree and the distance in 

 feet is equal to the height of the tree. It is the old 

 problem of similar triangles. 



Getting the Contents of a Tree. The contents of a 

 tree are generally expressed in terms of cubic feet 

 (a cube one foot on each side) or board feet (a 

 board one foot square and one inch thick), while fuel 

 or excelsior wood are commonly sold by the cord 

 (a pile four feet wide, four feet high and eight feet 

 long). 



The board foot is the most common unit in this 

 country and while not entirely scientific it is convenient 

 because it gives an idea of the amount of sawn lumber 

 that may be obtained from a given pile of logs. 



On a logging job, the amount of timber in a skidway 

 full of logs is obtained by scaling. The "scale stick," a 

 straight piece of hickory tipped with metal and marked 

 with figures, showing contents of logs of different lengths 

 and diameters, is applied to the small end of the log 

 inside the bark. If the log is ten inches in diameter 

 and sixteen feet long the contents are read from the scale 

 stick. Each log is scaled in this way and the contents 

 entered in a tally book. There are a variety of scale 

 sticks in use in different parts of the country based on 

 the different log rules. A log rule, by the way, shows 

 the contents of logs of different diameters and lengths 

 while a volume table shows the contents of trees of dif- 

 ferent diameters and heights. There are over forty log 

 rules in use in the United States. The Doyle, Scribner, 

 Maine, International, and Spaulding are among the 

 most important. 



In case it is desired to find out how much timber there 



