124 PRACTICAL FOREST MANAGEMENT. 



(c) Over established reproduction the overwood can hardly 

 be felled too heavily except in areas in which possibility 

 of frost damage prohibits the absolute clearings of over- 

 wood over too wide areas." 



Since the above was written much further light has been 

 thrown on the problem of the regeneration of sal. An essay in 

 the Indian Forester on " Natural Regeneration " 49 summarises 

 the factors necessary to regeneration and deals with the somewhat 

 divergent views at that time existing. Hole has examined in 

 detail the whole subject of the oecology of sal 50 and has thrown 

 considerable light on the development of the seedling. The Forest 

 Pocket Book contains the latest information available in the 

 Research Circle which goes to show that 



(1) Burning the leaf layer induces profuse reproduction. 



(2) Under a close canopy this reproduction gradually fades 



away and largely disappears. 



(3) With somewhat heavy opening of the canopy seedlings 



already on the ground improve greatly, stop dying 

 back and start to grow up. 



The last conclusion is not yet absolutely proved, but all the 

 silvi cultural experiments tend to show that this is so. 



In the particular conditions of Dehra Dun a great deal of the 

 new regeneration will consist of coppice from the great quantity 

 of suppressed advance growth already existing on the ground. 

 This is considered just as desirable as seedling reproduction ; 

 consequently where this state of affairs exists all that is necessary 

 is to select the seed trees for retention and to cut everything else. 

 This has been done experimentally with very excellent results as 

 may be seen at Lachiwala. 



The silvicultural system therefore resolves itself into regenera- 

 tion under a shelterwood either by coppice or seed and the retention 

 of the overwood for so long as it is required for seed production or 

 .as a frost protection to tha new crop. 



49 Natural Regeneration Indian Forester, October, 1921. TROWSCOED. . 



50 Indian Forest f^etorJi. Vol. V, part IV, Vol. VIII, part II, Oecology of Sal. HOLE- 



