178 ELEMENTS OF STLVICULTUEE. 



system for a time, and to increase the reserve by 

 leaving numerous standards. 



These facts being assumed, let us suppose a 

 coppice hitherto worked with a rotation of thirty- 

 five years, and which is to be converted into high 

 forest. 



It is necessary first of all to determine the length 

 of the regular (or normal) rotation to be applied to 

 the future high forest, to divide it into periods and 

 to define in the working circle an equal number of 

 blocks. The object of this is to ascertain in what 

 portion regeneration operations ought to be com- 

 menced, and therefore what portion should form 

 what is termed the first Block. Suppose the 

 rotation to be 180 years, and to be divided into five 

 periods of thirty-six years each. 



If the first Block contains a numerous reserve, and 

 if, at the same time, the underwood is sufficiently 

 old for the purpose, regeneration operations may be 

 undertaken at once during the first period. During 

 this interval, the Block which is to be regenerated 

 during the second period, must be allowed to grow 

 on, and only improvement operations, cleanings, 

 and thinnings (usually termed cuttings preparatory 

 to regeneration, or simply preparatory cuttings) 

 must be made in it. The rest of the working 

 circle must be treated as coppice with standards, 

 cutting -^g- of the area annually. During the 

 second period, cleanings and early thinnings should 

 be made in the first Block, regeneration operations 

 executed in the second, preparatory cuttings in 

 the third, and copsing in the remaining two, and so 



