HISTORIC SKETCH 9 



came rapidly into general use both in North Germany and 

 in Thuringia. 



The demand for timber continuing to increase, it became 

 compulsory, or at least highly desirable, to institute definite 

 plans for the regulation of the yearly fellings. 



Until woods which had been recently formed became of 

 serviceable size, the older forest was the only source of supply, 

 and the object of these early working plans was so to allocate 

 the annual fellings that the old forest would not be exhausted 

 before the younger woods were available. 



Two fundamentally distinct ways of attaining this end 

 occur in practice. The forest may be divided into sections 

 of approximately equal area. The number of parts is made 

 to correspond to the number of years over which it is desired 

 to spread the fellings, and one of the sections is then felled 

 each year. 1 The alternative method is to make an estimate 

 of the total stock of timber, and this amount, divided by the 

 number of years over which its utilisation must extend, gives 

 the quantity that can be felled annually. 2 It was some time 

 before it was appreciated that to this estimate might be added 

 a quantity representing the wood increment during the rota- 

 tion or lifetime of the trees. 



The former of these two ways appears to be, and often is, 

 the simpler, and, as previously mentioned, it was the first to 

 be employed (in the fourteenth century). In large forests, 

 however, the measurement and division of the area were 

 beyond the skill of the times to deal with, while the nature 

 of the crop was too uneven to admit of the method being 

 successfully applied. The method of calculation by volume 

 was accordingly resorted to, but in its roughest form. The 

 earliest information on this point dates back to the middle 

 of the sixteenth century, and refers to the Harz and the 

 district of Salzkammergut, in Upper Austria. 



1 See p. 134 : " Method of Periods by Area." 



2 See p. 135 : "Method of Periods by Volume." 



