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AMERICAN FORESTRY 



to a study of the valuation of trees and am convinced that 

 some standard of valuation should he adopted. 



In analyzing the various methods now in use it seems 

 that the most accurate way of estimating the value of a 

 tree is by means of its basal area, as this is the best 

 graphic indication of the tree's size of crown, which. 

 after all. is the real valuable part of the shade tree. 



DAMAGED ELM, VALUE $142.55 



If f hi* was not injured by the high tension electric wires it would be 

 worth, o City Forester W. W. Colton estimates, $199.56. 



No accurate basal area factor can be derived that will 

 be equally valuable for all species. It becomes apparent 

 then that we must first obtain a value per square inch for 

 basal area that has some definite foundation, and then 

 arrange a sliding scale of deduction factors for various 

 species, according to their specie value, that is, rate of 

 growth and resistance to insects, disease, climate and 

 present physical condition. 



To obtain the first, the sugar maple was selected as 



a standard species, because it has been more commonly 



planter! for the past fifty years than any other tree, and 



lave more available data in regard to it. In order 



a definite figure to apply to the basal area, we 



based mir calculations <>n the amount of money invested 



in growing a tree to a diameter that would produce that 

 basal area. This includes the original cost of the tree, 

 its planting and maintenance. By using the best available 

 tigares for a sugar maple, we found that the average 

 value per square inch of basal area at the end of fifty 

 years is 64}4 cents. This is the value for an ideal tree 

 under perfect conditions. 



The next step was to obtain a scale of reduction factors 

 for species and condition. It is evident that by the use 

 of this method the value placed on a 12-inch fast growing 

 tree would be the same as on a 12-inch slow growing tree, 

 whereas the actual value of the slow grown tree would be 

 much more. For instance, from a standpoint of interest 



IMPERFECT ELM, VALUE $51.96 



The high tension electric wire passing through the branches of this 

 tree has seriously impaired its value and will still further injure it. 

 If it was in perfect condition it would be worth $181.54. 



on investment and maintenance, a 12-inch beech would 

 be worth very much more than a 12-inch poplar. 



To obtain a deduction factor, the most common species 

 were divided into five classes, according to their rate of 

 growth, and a proportional deduction made for each class. 



As all trees are not equally valuable on account of their 

 susceptibility to insects and diseases, they were again 

 divided into five classes and the same deductions made. 



One more reduction factor was necessary to complete 

 the list, that for the present physical condition of the 



