Part II] Hole : Regeneration of Sal (Shorea robusta) Forests 61 
in all cases, the surface covering of dead leaves and humus 
was carefully swept off before sowing, see l.c. part II, 1916, 
paras. 14, 22, 36, Plates III, IY, V, VI, VII, IX and present 
paper, paras. 22, 23 (6), 23 (8), 31, 32 (1), 36, 37, 40, 41 (4), 
41 (5), 45, 46, Plates III, IV. 
(20) During the rains, the soil (upper 6 ins. layer), in the shade 
plots, invariably contained more water and organic matter 
than that of the open plots and this was correlated, in the 
shade, with more deaths during the rains (accompanied by 
more or less extensive root rot) and more deaths from drought 
in the dry season as a direct result of the poor root develop¬ 
ment in the rains. The inferior results in the shade plots, 
therefore, are believed to be due mainly to bad soil-aeration, 
see l.c. part II, 1916, paras. 16, 19, 22, 23 (2), 23 (5). 
(21) The inferior growth of sal seedlings on loam, in the shade, 
during the rains, can be improved by exposing the soil to 
the air and preventing the accumulation of dead leaves, see 
l.c. part II, 1916, para. 23 (4). 
(22) The inferior results in the shade are not primarily due to 
deficient light, inasmuch as good seedling growth has been 
obtained in the Dehra Dun garden under artificial shades 
giving a light intensity less than that in the darkest experi¬ 
mental plot. Excellent seedling growth has also been 
obtained in the forest shade plots in a year of good rainfall 
by sowing in pots filled with sand,* see l.c. part II, 1916, 
paras. 13, 15, 28 (2). 
(23) The growth of sal seedlings in sand, both in the shade and 
in the open, is improved by the addition of dead sal leaves 
to the sand. This increases the water content of the sand, 
diminishes deaths from drought and produces more vigorous 
seedlings, as judged by the height and dry weight of the 
stems and length of the roots, see l.c. part II, 1916, paras. 
27, 28 (5) and present paper, paras. 18, 19. 
(24) The greatly superior results obtained in the cleared patches 
and strips, as compared with those obtained under shade, 
see (19) and (20) above, are, therefore, mainly due to two 
factors : 
* As regards this point, it must be remembered that, in a year of short rainfall, the 
seed and seedlings in sand are likely to suffer from drought and, in order to secure good 
results in such years in sand, artificial watering is necessary. See also ( 15 ) above, 
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