FOREST DISEASE SURVEYS. 3 
In most cases the appraisal of a timber-sale area is based somewhat 
low in respect to the total feet board measure of sound material, 
principally on account of the unknown amount of defect or rot to oe 
encountered and sometimes partially for other causes, foremost of 
which is the desire to prevent overestimation. 
_ In timber surveys the estimating of timber is performed by mem- 
bers of the party who have been trained to estimate stands of varying 
“mixtures, age, and soundness and who are thoroughly capable of 
; 
4 
% 
. 
Fic. 2.—Fruiting bodies of Trametes pini on lodgepole pine. Notice the swell- 
ing of the trunk where the fruiting bodies are attached. (Photographed by 
G. G. Hedgecock.) 
_ judging the board-feet contents of trees within reasonable limits of 
error. The addition to the party of an expert cruiser has been 
made as a means of aiding the estimators in this work and checking 
their results. The determination of the correct cull percentage ie 
to rot is the aim of this arrangement in the crew. 
__ In certain types and ages of stand the estimate may come close to 
the true scale, but, again, too small a percentage is deducted for cull 
due to rot, and consequently the estimate runs too high. A sale con- 
tractor figuring possibly on a conservative margin and accepting the 
oe 
