220 THE PRINCIPLES OF HANDLING WOODLANDS 



the benefit of two or more co-dominant or intermediate 

 trees. 



Frequently the removal of an old straggler or of de- 

 fective trees makes openings of a permanent character, in 

 which natural reproduction takes place. Nevertheless, 

 this is an improvement cutting, not a reproduction cut- 

 ting. The whole aim is to improve the immature stand. 

 If the defects and irregularit}' of the stand result in open- 

 ings large enough for reproduction, this cannot be 

 helped; and in that case the cutting is so made as to get 

 as good natural reproduction as possible. In most of the 

 thinnings only temporary openings are made. 



Improvement Work in Selection Forests 



In selection forests, thinnings are sometimes made — 

 provided there is a market for the product — for the bene- 

 fit of the immature trees. Stich thinnings are made at 

 the time the mature trees are cut. In principle, thev are 

 of the same character as those just described for irregular 

 second-growth stands. The good specimens of all ages 

 are protected by removing undesirable crowding indi- 

 viduals. Seedling growth is aided by cutting away poor 

 specimens over it, and sometimes even b\- cutting advance 

 growth and brush, just as in a cleaning in an even-aged 

 group. In such work, the principles of practically every 

 kind of cutting are employed — cleanings in young 

 groups, thinnings in even-aged patches, and damage- 

 cuttings in injured young groups. 



