THE WORKING SECTION. 295 



4. The Working Section. 



All parts of a working circle, which form one separate series 

 of age classes, are called a working section. If a working 

 circle consists of only one series of age classes, it is identical 

 with a working section. In working circles of some extent, 

 however, different conditions may demand the establishment 

 of two or more series of age classes, or a division of the 

 working circle into two or more working sections. The prin- 

 cipal causes, which demand the formation of working sections, 

 are the following : 



a. Species. 



If several species appear as pure woods in a working circle, 

 they must be placed into different working sections, if they 

 require essentially different treatment, or if a certain quantity 

 of material of each species has to be cut annually. If, on the 

 other hand, the several species appear in mixed woods, such a 

 separation is neither practicable or necessary. 



b. Sylvicultural System. 



Each sylvicultural system may demand the formation of a 

 separate working section. If, for instance, part of a high 

 forest is treated under the compartment system, and another 

 part as a selection forest, each part must be formed into a 

 separate working section. Coppice woods, and coppice with 

 standards always must form separate working sections. 



c. Rotation. 



Even in the case of the same species and sylvicultural 

 system, areas worked under different rotations must be placed 

 into different working sections, whenever an even or ap- 

 proximately even annual yield is expected. Unless this is 

 attended to, it will happen either that the annual yield is 

 uneven, or, if the same quantity is cut every year, that the 

 different rotations merge into one. 



