54 THE THEORY AND PRACTICE OF WORKING PLANS 



boundary of the working unit is, as far as limitations of owner- 

 ship permit, an economic one within which the marketing of 

 timber is controlled by certain factors of consumption or dis- 

 tribution. Economic reasons may warrant the over-cutting 

 on one administrative unit and the under-cutting on another, 

 but if a sustained yield from the entire market unit is main- 

 tained it is of small moment if the stand on one or more of the 

 administrative subdivisions is over-cut. 



This broad construction is of course adapted to the extensive 

 conditions existing in most parts of America. In Europe, e.g., 

 in Prussia, it has long been customary to require a sustained 

 yield by administrative units — i.e., for each oberforsterei or 

 supervisor's area- — recently it has been extended in Prussia to 

 cover each ranger's district I But in America the unit of regula- 

 tion, the working unit, must be practical, must be the market 

 unit, just as the subdivision, the block, usually is the main logging 

 unit. 



WTiere administrative unit areas belonging to the same 

 owTier are far apart or exceedingly large, they are not included 

 in the same working unit. E.g., it would be preposterous to 

 make a single working plan for the two divisions of the Florida 

 National Forest or for the whole complex of contiguous national 

 forests in Washington and Oregon. But it is entirely correct 

 and logical to combine, e.g., the contiguous and similar Coco- 

 nino and Tusayan National Forests in northern Arizona. The 

 administrative boundary separating these two national forests 

 is a purely arbitrary one; they are essentially the same in 

 character and composition, and are parts of the same market 

 unit. 



The working unit is given some convenient local name 

 which is simple and characteristic. 



Object of Management 



At the working-plan conference between owner, admin- 

 istrator, and organizer, the object for which the forest is to be 

 managed must be decided, i.e., whether 



