176 A MANUAL FOR NORTHERN WOODSMEN 
b. Some 60 heights measured with the hj^psometer. These 
might have been averaged for each diameter class, but a better 
plan is to plot all the heights on cross-section paper and draw a 
curve through them as in the accompanying sketch. From this curve 
the average height of the 8-inch trees is read off as 50 feet, of the 
9-inch trees as 55 feet, and so on. The larger trees of the grove, 
those 16 inches and over in diameter, a’veraged 80 feet in height. 
c. From the proper volume table the contents of a single tree of 
each size class is now taken and multiplied by the number of trees 
in the class. For the tract in question Table No. 4 gives the 
figures wanted, the product of the trees in boards, both round-edged 
and square-edged lumber. In this, table the contents of a tree 8 
inches in breast diameter and 50 feet high is given as 50 feet B. M.; 
that of a tree 9 inches x 55 feet, 70 feet, and so on. No discount 
appearing necessary for defects, by addition of the contents of the 
size classes the total stand of the lot is obtained. This comes to 
253 M feet, of which in the practice of the locality 20 per cent may 
be sawed into good plank, 30 per cent into edged boards, and the 
balance of 50 per cent, the smaller trees and rougher logs, put into 
round-edged box-board lumber. The recorded figures, the plot 
and height curve, and a table showing the way the figures are put 
together, are given on the preceding page. 
The estimate after this fashion of 250 M feet of timber 
of this size is a light day’s work for two men. Three men 
form an economical crew for big jobs. 
3. In the valuable timber lands of the Lake States and 
South it is customary to estimate each forty acres by 
itself, and the methods of estimation frequently cover 
the whole stand. Pacing is largely used as a measure of 
distance, and the cruiser is generally equipped with some 
kind of volume table giving as often as not the board 
contents of trees of different diameters yielding 2, 3, 4, or 
5 16-ft. logs. Usually two men w r ork together. In that case, 
the helper may run a compass line across one end of the 
“ forty,” ten rods or so from its boundary, leaving marks 
enough so that on the return trip it can be followed. 
Through the strip so cut off the cruiser circulates, keep¬ 
ing watch of his other bound and scoring down, as he 
passes, the merchantable trees according to species and 
in appropriate classes. As a rule very little measurement 
of height or diameter has been done in the past! The two 
men keep abreast of one another. When one strip has 
been covered another is taken in the same way. After 
the whole “ forty ” has been covered addition of the 
