TIMBER ESTIMATING, 89 
An attempt should not be made to apply this system of tallying 
only J tree in 5 or 10 to narrow strips, where only a small per cent 
of the stand is counted. On a 4-rod strip, the diameters of all 
trees should be tallied. But where at least 5 percent, and pref- 
erably 10 per cent, of the stand is actually recorded it is seldom 
necessary to go further and tally the diameters or heights of 50 
per cent. | 
The chief merit of the method is that it enabies a cruiser to 
cover his territory more thoroughly, and at the same time avoid 
the necessity of guessing at the average heights or volumes of the 
counted trees. 
ACCURATE PLOT SURVEYS. 
In certain scientific work it is necessary to determine accurately 
the contents of sample plots as, for example, in the studies of 
erowth and in the determination oi the future yield of forests. 
Inasmuch as the average woodsman does not have occasion to make 
such studies, the various methods of determination of the volume* 
oi stands is not included in this work. 
THE CHOICE OF METHODS FOR ESTIMATING. 
For inexperienced men who have not the training necessary to 
enable them to use ocular methods and judgment, there are but 
two plans available for estimating timber. First, the 4-rod strip 
or valuation survey, where the diameters are calipered and heights 
measured with an instrument and the volumes obtained from a | 
volume table. Second, a modification of this in the form of plots 
laid out systematically at definite distances on a compass course 
with all of the trees carefully measured and their volumes computed 
by volume table. Either of these systems is applicable anywhere 
in any kind of timber, but the accuracy of the results will depend 
on the soundness of the timber, care in elimination oi dead and 
worthless trees, per cent of total area covered, accuracy of the 
volume table used, care with which differences or types in the 
stands are distinguished, judgment in selecting for measurement 
average heights with the hypsometer, and care in observing the 
width of the strip. 
Foresters or cruisers with training and ability to use ocular 
methods, when working alone, will obtain best results by using 
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