1 APPENDIX. 



Thinnings permit of the realisation of the legitimate inter- 

 mediate yields, they shorten the rotation and improve the quality 

 of the final crop. They are essential under all silvicultural 

 systems and their neglect in working deodar under selection in 

 Jubbal has been most unfortunate. Innumerable instances can 

 be given where thinnings in sal and oak worked under selection 

 are the crying silvicultural need of existing crops. 



The degree of the thinning will vary with the species being 

 dealt with. It is impossible definitely to describe what constitutes 

 a correct thinning, but the experienced silviculturist will know 

 exactly what degree of density is desirable in each and every case 

 and will act accordingly. The golden rule is to begin early, thin 

 moderately and repeat as often as necessary. The art of thinning 

 can only be acquired by experience, observation and thought, 

 but there are now fortunately plenty of trained foresters, who are 

 quite competent to do this work under the direction of a Divi- 

 sional Officer, who knows and can explain exactly what he wants. 

 Mclntire in speaking of deodar has stated : " I have come to the 

 conclusion that in thinnings one should be guided entirely by the 

 condition of the canopy formed by the dominating stems. The 

 removal of the suppressed poles occupying little or none of the 

 space in the canopy appeared to me to be quite a minor consi- 

 deration." Again Broillard writes : " Pine woods require early 

 thinning, failing this the trees languish." Where snow break or 

 strong winds are to be feared, the sole method of preventing loss is 

 by thinnings which prepare the trees for an isolated condition and 

 strengthen their stems and root systems. 



Thinnings promote not only diameter but height increment, 

 Chavegrin is positive on this point : " It is believed that trees 

 grown under crowded conditions are more rapidly drawn up and 

 attain greater length of bole. The error of this assumption has 

 been long since revealed by .research. In truth trees of the same 

 age growing in a dense ycrop are far behind those standing in 

 rational freedom, the greater the number of stems per unit of 



