FOREST PATHOLOGY IN" FOREST REGULATION. 25 



that are included in our computations, the narrower will be the 

 margin of error. Besides, in practical work, the age is generally 

 counted at a stump height of 18 inches, and, since for all purposes of 

 management we have to deal with the standing tree where diameter 

 is the only indicator of age, it is of little importance whether the age 

 counted is absolute, within narrow limits, as long as all figures are 

 directly comparable with each other. Moreover, in practice it is 

 impossible to have all trees cut at exactly 18 inches. With the 

 greatest of care, the stump height will vary. It is an easy matter, 

 where desired, to add a number of years corresponding to stump 

 height as soon as reliable figures, which now are lacking, are obtainable. 



The limbs and branches are now lopped off and the brush piled for 

 burning. 



In the bucking of the bole some judgment should be used, guided 

 by the object of the study. We want to find all traces of decay in 

 the bole and take exact measurements of them. Obviously, then, 

 the aim of the dissection must be to open up the tree in such a way 

 that no decay can escape the observer. It would not do, therefore, 

 to buck all trees in even log lengths of the usual commercial measures. 

 A straight, clean bole without any blemish whatever is bucked in 

 16-foot logs, which then are individually split; this will, as a rule, 

 bring out any hidden decay. Both the cross sections at the opened 

 surfaces of the split wood must be searched very carefully for any 

 abnormal sign. This makes full knowledge of the properties and 

 aspect of the normal wood a prerequisite. In the beginning, there- 

 fore, it is advisable first to study very closely the sound, normal wood 

 of the species, until the operator is able to detect at a glance and 

 automatically any deviation from the normal. The success of the 

 study hinges upon the development of personal skill in judging wood. 

 In order to prevent the dulling of this sense during the course of the 

 work, check studies of perfectly sound wood will prove very bene- 

 ficial. Any slight real or apparent deviation from the normal in 

 physical properties or aspect, particularly in color, must be followed, 

 of course, to its source. 



Trees without any blemish are rare; generally there is either some 

 irregularity in form, fork, unusually heavy branching, or there are 

 sporophores of fungi, badly healed-over branch stubs, swellings, de- 

 pressions, catfaces, fire scars, lightning scars, or frost cracks and frost 

 ridges. In choosing the proper places for bucking, it is generally 

 advisable to start at the most salient malformations or defects; they 

 will often lead to the focus of decay, if there is any. In case of fail- 

 ure, the less prominent defects are investigated, and so on down the 

 line until there is no doubt left that no decay is present in the bole. 

 Particular attention must be given to branch stubs, which, by extend- 

 ing through the sapwood to the outside of the tree, offer an easy 



