PRACTICE OF TIMBER ESTIMATING 
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1. Type and Plot System 
According to this method the land to be passed on is 
divided up into types of known area and approximately 
like stand, without, however, necessarily leaving marks on 
the ground. Through these subdivisions of his area the 
cruiser travels, studying the size, height, density, and con¬ 
dition of his timber, and forming as he goes an estimation 
of the average stand. This estimate he checks by a number 
of sample plots, run out with the tape, and examined with 
care. The plots are usually laid out either in square 
or circular form, though the strip system is perfectly 
applicable. 
Very satisfactory results have been arrived at by this 
method where a considerable area in sample plots has 
been surveyed or where the estimator is a man of judg¬ 
ment and experience. But choosing a few sample plots to 
represent a tract is recognized as a very delicate matter. 
Beginners generally select too good a piece, and the man 
who is really competent to do it can usually make a close 
guess at the whole thing. As with all other methods of 
estimating, area should be known from surveys, and that 
in not too large units. 
A good example of the application of this 
system comes from a national forest super¬ 
visor who had to estimate for a timber sale 
a tract of some 1200 acres. It lay in the 
form shown, with a ridge running down 
the middle of it, which naturally formed 
the first line of subdivision. The tract was 
therefore surveyed with compass and chain and a dividing 
line run along the ridge top. 
Then on each side of the ridge three distinct types of 
timber stand were recognized. The heaviest timber, red 
fir of good size, was in the middle; the north end was 
lighter, with a mixture of lodgepole pine; the south end 
had been damaged and rendered very thin by fire. These 
blocks were therefore blazed out and roughly surveyed. 
Thus the land was divided into six compartments of ap¬ 
proximately even stand and of known area. 
