204 THE ROTATION. 



5. The PJii/Hical Hotatio)!. 



By the physical rotation is generally understood that age, 

 which is most favourable for the natural regeneration of a 

 species, taking into consideration the conditions of the locality 

 and the sylvicultural system. It cannot be lower, in the case 

 of high forest, than the age, when the trees have commenced 

 to bear good seed in sufficient quantity, nor as high as the age, 

 when the production of good seed has ceased ; the best period 

 being that about the end of the principal height growth. 



In the case of coppice woods, the age must be ))elow that, at, 

 which the trees cease to produce good healthy shoots, when 

 cut over. 



Sometimes a second physical rotation is mentioned as that, 

 which coincides with the natural lease of life of the trees. It 

 is only of interest in the case of protection forests, parks, etc. 



6. Choice of Botafion. 



The choice of rotation, or the age at which a wood is to 

 be cut over, is, as already stated, one of the most important 

 questions in forest management. Many and varied are the 

 arguments, which have been advanced in favour of the one or 

 other rotation. 



One party maintains, that the financial aspect should decide 

 the choice of rotation, since forests represent capital, which 

 should yield the highest possible interest. Another party 

 brings the general usefulness more into the foreground and 

 maintains, that other considerations are more important to the 

 general community than purely financial results, especially 

 in the case of State forests. 



In the author's view, the "objects of management" should 

 determine the rotation. These frequently demand deviations 

 from the financial rotation. For instance, to begin wath an 

 extreme case, for protection forests generally a very high 

 rotation is indicated ; where a nation considers it necessary 

 to produce timber fit for naval construction, a rotation, which 

 lies far beyond the financial rotation, is called for ; where 



