THE PROBLEM OF MAKING VOLUME TABLES FOR 

 USE ON THE NATIONAL FORESTS^ 



By Thornton T, Munger 

 Forest Bxaminer, Forest Service 



The measurement of the volume of a standing tree is a difficult 

 operation, but a most necessary one for the forester. It is fundamental 

 to the management of a forest property, and is, therefore, a phase of 

 forestry which has received much attention. In a brief paper it will 

 not be possible to go into the intricacies of the problems that confront 

 us in making volume tables for National Forest use, but I should like 

 to call attention briefly to the part that the Branch of Research should 

 play in the preparation of volume tables, to sketch some of the questions 

 that arise in their preparation, and to suggest some of the principles 

 that, it seems to me, should guide the work. I hope that in the discus- 

 sion to follow we may have an interchange of views that will throw 

 much needed light on this subject and show the way to constructive 

 improvement in our volume-table practice. 



The difficulties in the measurement of standing trees arise not only 

 because most of the tree is out of reach and because there are so many 

 of them but because no two trees are alike, and because they are not 

 of a regular geometric shape. If the used portions of trees were 

 regular in shape and their volume followed some mathematical law, we 

 investigators would probably not be concerned with a study of the 

 principles of volume^table construction. It would merely be for the 

 mathematician to tell us the shape of the tree, and the problem of 

 measuring standing trees would be settled. For years there has been 

 an effort to find a rule of thumb by which the volume of any tree could 

 be arrived at, but all rules of thumb and formulae require measure- 

 ment which it is not convenient to make, and are, therefore, imprac- 

 tical in actual use. Measurements of the contents of individual stand- 

 ing or down trees can be secured very accurately by careful instru- 

 mental measurement of the bole of the tree. This is practicable only 

 for detailed scientific work, such as in volume-growth or yield studies. 

 The present discussion is concerned merely with the preparation of 



1 Paper read at the Forest Investigations Conference in Washington, D. C. 

 March 1, 1917, slightly revised. 



574 



