32 THE THEORY AND PRACTICE OF WORKING PLANS 



Large pole — a tree from 8 to 12 inches d.b.h. 

 Standard — a tree from i to 2 feet d.b.h. 

 Veteran — a tree over 2 feet d.b.h. 

 g. Form of trees: long or short boles; clear or limby; 

 straight or crooked. If saw timber, the number of 

 sawlogs (16 feet long) per tree and per M. feet, 

 board measure. 

 h. Condition: health, and apparent vigor of growth. 



13. History of the stand: treatment by man; damage by fire, 



grazing, insects, diseases and atmospheric agents. 



14. Merchantable condition of the trees. Reductions for 



defect; per cent of probable output of different grades 

 of lumber. 



15. Site class (forest-producing power of the locahty). Use 



five grades, I, II, III, IV, V. I is best site. Should 

 express the capabihty of the tract rather than the pres- 

 ent production. 



Note. — Many American authors use only three grades, I, II, and III, I being 

 the best site and III the poorest site. 



These subjects need not be treated exhaustively; the forest 

 description must, above all, be practical and brief. 



The unit of area in forest description depends, of course, 

 on the degree of intensity possible in the working plan. The 

 ideal unit of description is the stand. The stand is that portion 

 of the forest which is so essentially different in forest type, in 

 method of management, in component species, in age, in density 

 of stocking, or in quality of site, that is clearly distinct from the 

 surrounding forest. The stand as a unit of forest description is 

 ideal, since it is at the same time the true unit of silviculture 

 and forest organization. But the necessity of pushing the 

 reconnaissance work and the size of the working plan area often 

 makes it more feasible to confine the description to the survey 

 unit — such as the section — or to an entire watershed (in unsur- 

 veyed and very mountainous country), leaving it to the forest 

 organizer to combine the various descriptions and smooth 

 out their differences and discrepancies into a general forest 



