INDIAN FOREST RECORDS 
Vol. VIII.] 
1920 
Part II 
The Regeneration of Sal (Shorea robusta) Forests. 
A Study in Economic Oecology. 
by 
R. S. HOLE, C.I.E., F.C.H., 
Botanist, Forest Research Institute, Dehra Dun. 
CHAPTER I. 
General outline of work undertaken. 
1. The regeneration of the sal forests of northern India is, at present, 
often a very slow and uncertain business, the seedlings dying back more 
or less completely for a number of years before they finally produce a 
vigorous persistent shoot.* 
With the object of discovering a method of speeding up the growth 
of sal seedlings, and of quickly regenerating these forests, an oecological 
study of the factors influencing the development of sal seedlings was 
undertaken at Dehra Dun during the years 1909-19. 
The general lines of work adopted were as follows 
(1) A series of preliminary experiments was carried out in the 
Dehra Dun Experimental Garden to test the effect of soil 
composition, soil moisture, soil aeration and light intensity 
on the development of the seedlings. The object of these 
experiments was to obtain an indication as to which of 
these factors were likely to be most important and the 
precise effects of such factors on seedling development. 
(2) Seedlings were grown in the local sal forests near Dehra Dun 
in different localities, both in the shady forests and in the 
open. These experiments were repeated for several years 
in order to obtain average results, unaffected by excep- 
* For examples of such seedlings see Indian Forest Records, V. 4, part II, 1910, Plate I. 
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