Nomenclature of Divisions of Area. 425 



system, would give a sustained yield of cordwood or mining 

 timbers. In this case, as soon as 'the management prescribes a 

 separate silvicultural system and separate regulation of the cut 

 for part of the already existing working circle, a new working 

 circle is formed. The new working circle should, however, not 

 be called a Division, but be named after its product, e. g. "the 

 mining timber working circle of the Bear River Division" or 

 the cordwood working circle of the Crystal Lake Division. 



Where two distinct working circles are tributary to markets 

 which do not require sustained yield — as, for example, export 

 markets, — the working plan may be simplified by combining the 

 two Divisions, at least in so far as the regulation of the cut is 

 concerned. When, however, one or both begin to need sustained 

 yield, a separate regulation must be made for each. 



Division of the Working Circles into Blocks. This division is 

 made to assist in regulating the cut, and should be on the basis 

 of logging units or groups of logging units, the boundaries de- 

 pending entirely upon topography. The Block should receive 

 a suitable local name, generally taken from the watershed of the 

 stream which it covers. 



Division into Compartments. The basis will be a single log- 

 ging unit or year's cut. The designation should generally be by 

 means of numbers. This division need be made only in the more 

 intensive working plans. 



There can not be too much emphasis laid on the importance 

 of deciding upon these divisions of the area, both during the 

 progress of the field work and in drawing up the working plan. 

 There should be a complete knowledge of such matters as pres- 

 ent market conditions, lines of transportation, outlets for the 

 timber and the probable changes and developments in all three. 

 Changes of divisions once decided upon, except in the inaces- 

 sible parts of a forest may involve a complete overhauling of the 

 working plan and cause much confusion. Because of this, if 

 changes in market conditions, transportation systems, or out- 

 lets are liable to occur and can be foreseen, it is well to provide 

 for them in the working plan. This may sometimes require a 

 separate regulation of the cut with a different annual yield for 

 two possible contingencies. For example, given an area at 

 present tributary to a certain market; this area now forms a 

 working circle. But there is a possibility of a railroad being 



