Part IT"] Hole: Regeneration of Sal (Shorea robusta) Foresti 15 
‘•f.vj leaves and in those without dead leaves. Plate II 
1, shows the plants in loam pots 15, 18, 14 and 19 on 
December 4th, 1917 and Plate II Fig. 2 shows the plants in 
sand pots 22 and 23 on the same date. 
(2) In the forest loam in pots 11, 14 and 19, the layer of dead sal 
leaves has had a decidedly injurious effect in increasing the 
number of deaths and reducing the root-growth, whereas 
in the sand pots the effect of the dead leaves has been rather 
beneficial in both respects. 
Summary of Conclusions. 
20. The observations recorded above justify, it is believed, the 
following conclusions :— 
(1) The results previously obtained by Mr. R. S. Troup and the 
writer have been confirmed, and it has been shown that a 
layer of dead leaves on the surface of the soil has a decidedly 
injurious effect on germination and the early growth of sal 
seedlings, the injurious action being three-fold : 
(а) A drought action, owing to the dry barrier separating the 
seed from the soil surface, which causes the death of the 
seed either before, or shortly after, germination has com¬ 
menced, see paras. 9, 10, 11 and 12 (1) (2) (4) (8). 
(б) A mechanical action due to the obstruction afforded by the 
tough leaves to the passage of the radicle. When moisture 
and temperature, therefore, are suitable for the continued 
growth of the radicle, the latter instead of penetrating 
vertically downwards into the soil develops horizontally 
between the layers of leaves. In consequence of this the 
plants inevitably die from drought so soon as the dead 
leaves and surface soil dry out, see para. 12 (2). 
(c) An injurious action which comes into play after the radicle 
has penetrated the soil, and which is provisionally ascribed 
to a bad soil-aeration effect. It directly causes an appreci¬ 
able number of casualties, and also diminishes root-growth. 
It is active in sal forest loam which is kept moist but is 
inoperative in clean sand. How long this action is 
capable of retarding growth remains to be determined 
by future work, it is possible that it is chiefly injurious 
to young seedlings which have their delicate young roots 
in or near the soil surface, see paras. 14, 15, 18, 19. 
(2) Sal seeds are especially liable to damage by drought. By 
care in storage, by keeping them shaded, cool and by prevent- 
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