THE ART OF THE SECOND GROWTH 



1. Removal of trees and poles acting as suppressors; 



2. Removal of inferior trees and poles acting as competitors; 



3. Partial removal of a superstructure on a regenerated area; 



4. Removal of less desirable individuals acting as seed-trees, 

 c. Reduced danger from fire, fungi and insects. 



II. Kinds of improvement cuttings are: 



a. Improvement cuttings in primeval woods. 



b. Improvement cuttings in culled woods. 



III. Marking: Trees and poles to be removed in an improve- 

 ment cutting must be individually marked by the sylviculturist. 



Generalizing rules for marking cannot be given; each tree or 

 pole must be dealt with according to its individual merits and 

 demerits. 



The marking of improvement cuttings by the forester is, con- 

 sequently, a timetaking affair. 



IV. Localities: Irregular, thin woods composed of a multitude 

 of species deserve improvement cuttings. 



The local market must allow of the— at least partial — utiliza- 

 tion of suppressing, competing, superstructing and less desirable 

 individuals. 



Paragraph LXII. Thinnings in seed forests. 



Thinnings proper are applicable exclusively to dense and fairly 

 even-aged groups or woods, in the thicket stage and in the pole stage 

 thereof, always under the proviso that a permanent road system 

 and a nearby market allow of a remunerative outcome of the act. 

 In Pisgah Forest thinnings are out of the question as the woods 

 are thin and irregular. At Biltmore, thinnings are made in the 

 polewoods of Yellow Pine. Up north, from the merely sylvicul- 

 tural standpoint, thinnings are possible in the Jack Pine woods, in 

 Balsam thickets, on Black Spruce slopes, in Lodgepole Pine 

 thickets, etc. 



Thinnings are not made to originate a second growth; they are 

 made within a second growth already at hand. 



A. Purposes of thinnings: 



I. To develop the log diameter of large saplings and poles at 

 a time at which the log axis has been obtained. 



II. To increase the volume increment percentage. * 



III. To increase the quality increment of predestined mess- 

 mates. 



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