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JOURNAL OF FORESTRY 



same numerical terms mean the same thing where used with different 

 species. To accompHsh this it is necessary to reverse the ancient cus- 

 tom and give to the poorest sites the lowest numbers. Thus any site 

 capable of producing 10-40 cubic feet per annum, of any given species, 

 would be Site Quality I (or i) for that species; 40-70 cubic feet per 

 acre, Site II; 70-100, Site III; . . . 190-220 cubic feet per acre 

 would be Site VII (or 7). Thus, a high number would indicate a high 

 yield or increment, which would be only occasionally met with, while 

 ordinary forest lands would fall between Sites I and III. 



A range of 30 cubic feet within each grade is suggested because for 

 local description more minute subdivision may often be desirable, and 

 there is a natural tendency to divide data into either two or three 

 groups. Thus la represents 10-20 cubic feet per acre ; Ih, 20-30 ; Ic, 

 30-40. 



As distinguishing this "American plan" from the European usage, 

 it might be desirable to use Arabic rather than Roman numerals. 



The following table for lodgepole pine is not ample enough to show 

 exactly within what ranges of stocking the "normal" current increment 

 is obtainable, but does show that probably between the limits of 2,500 

 and 700 trees per acre, at the age of 55 years, the increment would be 

 essentially the same for all stands. These data were collected with the 

 primary object of determining the optimum stocking, and were all ob- 

 tained from small plots covering a range of not over one-fourth mile 

 and occupying different parts of a bench which showed no discernible 

 differences in site quality. 



Similarly, the writer found, in obtaining measurements on hickory 

 in 1907, that when small plots were chosen whose area was fully oc- 

 cupied, the increment was essentially the same over wide areas of uni- 

 form delta land, regardless of the age of the stand. These measure- 

 ments covered the range between 20 and over 200 years. 



It is not the purpose of this paper to analyze or criticise other bases 

 for site determination which have been proposed. It is worth while 



