4 BULLETIN 658, U. S. DEPARTMENT OF AGRICULTURE. 
estimate at its face value may find upon cutting the stand that a great 
deal more rot is encountered than was expected. This fact alone | 
could easily result in the logging operation turning out a loss instead | 
of a profit, especially if the logging chance is not a favorable one. | 
Such failures doubtless do not encourage the undertaking of further | 
contracts, and fewer timber sales are the result. This has its ultimate | 
effect upon the forest as a whole in an cconomic way. | 
Recent studies made of the rots occurring + in forest trees have | 
given information concerning the amount of decay prevalent in dif- 
ferent age classes and in different sites for a particular species of tree. 
These studies have indicated that the decay in a tree or a stand 
varies with such factors as age of stand, site, density, injuries, and 
moisture relations. Such being the case, a disease survey of the sales 
areas made either as a separate pathological survey or in conjunc- 
Fic. 3.—Typical rot of Trametes pini (honeycomb rot) in white pine. 
tion with the usual timber surveys would prove of immense value in a 
closer estimate of the sound board-feet contents of the stands.. A 
disease survey in conjunction with the timber-survey work would no | 
doubt be the more feasible plan of the two, since it would require 
no additional men for the crews and should not appreciably affect: 
the cost per acre. All that would be required in order to secure the 
disease data in more accurate form is the training of one of 
the members of each unit crew in the proper methods by which the. 
various pathological determinations are made. This would mean the 
ability to judge more accurately the cull percentage due to rot and 
the ability to recognize all the outward indications of decay as well 
as the principal fungi attacking forest trees. Preferably, the esti- 
mator should be the one selected to assume this duty, as it is his indi- 
vidual work which determines the total estimate and the cull percessa 
age of the stand. " 
1Meinecke, E. P. Forest pathology in forest regulation. U. S. Dept. Agr. Bul. 275, | 
62. p. 1916: 
