APPENDIX. 



Vll 



The essential point about a thinning, however, is that no 

 lasting interruption of the leaf canopy is created. 



Increment felling. (Lichtungshieb) includes all trees of classes 

 (2) to (5) even "when they are vigorous and healthy and not doing 

 damage to their neighbours, and usually a greater or lesser part 

 of class (1) as well. The essential point, however, is that a list- 

 ing interruption of the cover is created. This interruption always 

 lasts for a long period and usually for most of the remaining 

 life of the wood. It is therefore usually employed when some 

 form of soil protection wood is to be introduced either artifi- 

 cially, or naturally c/.; Eichenlichtungsbetrieb. 



Thinnings. 



The following kinds and intensities of thinning may be formed : 

 I. Ordinary thinnings (Niederdurchf or stung or Eclair cie par le 

 has). 



(1) Light thinning^A. grade). This is limited to the removal 

 of : 



(i) dead and dying trees and very badly suppressed boles ; 

 (ii) diseased trees, i.e., class (5) and a few of class (2). 

 This thinning is of little practical use and is seldom made 

 except for the purpose of comparative research with regard to 

 increment. 



(2) Moderate thinning (B grade) This consists in the removal 



of- 



of 



(i) dead, dying and much .suppressed trees ; 

 (ii) suppressed trees ; 



(Hi) spindly trees ; and branchyl advance growth which it is 

 impracticable or not desirable to prune or lop, and 

 diseased trees ; i.e., class (5) and (4) and part of 

 class (2). 

 (3) Heavy thinning (G grade). This consists in the removal 



(*) dead, dying and much suppressed trees ; 

 (ii) suppressed trees ; 

 (iii) dominated trees ; 



