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 
