164 A MANUAL OP FORESTRY. 



breadth of such strips should not exceed the height of 

 the mother trees, so that they may not only be quickly 

 and fully stocked, but in order to provide better protec- 

 tion for the young crop against climatic dangers ; the 

 soil keeps also fresher. 



Such protection is further increased if successive 

 clearings do not adjoin each other, but are separated 

 by older woods. Sometimes the clearings represent 

 patches situated in the middle of old woods. Arrange- 

 ments of this kind lead, however, to a very complicated 

 system of management; hence they occur only where 

 groups of trees have been thrown by wind, or snow, or 

 killed by insects. If patches are cut purposely, they 

 often lead to the group system described above. 



2. Merits of the System. 



Owing to the uncertainty of the seeding and the in- 

 juries to which the young tender plants are afterwards 

 exposed, the system can be recommended only under 

 favourable conditions of the locality and in case of 

 hardy quick-growing species. Damage by insects, 

 especially the cockchafer, Hylesinus, and Hylurgus 

 further narrows the limits of applicability. 



B. Natural Regeneration by Shoots and Suckers. 



It has been explained in Volume I.,* that woody 

 plants can reproduce themselves by means of shoots 

 or suckers, or both. Shoots may spring from the 

 stool, after the tree has been cut over close to the 

 ground, or from the stem and top, if the cutting is 



* See pages 174 and 213. 



