Stones, if not in excess, are advantageous in all soils inclined to be stiff, for they help to keep them open. But then they must not be large, as if so they act as badly as a rocky substratum preventing the descent of the tap-root.
The reason, I take it, why Tea thrives best in light soils is that the spongioles or ends of the feeding roots are very tender, and do not easily penetrate any other.
There is more nourishment in stiffer soils, but for this reason the Tea plant cannot take advantage of it.
If a chosen soil be too stiff, it may be much improved for Tea by mixing sand with it. However, even where sand is procurable near, the expense of this is great. When done, the sand should be mixed with the soil taken out of the holes in which the plants are to be placed (see [Transplanting]), and it may be done again later by placing sand round the plants and digging it in. All this though is extra labour and very expensive, so none but a good Tea soil should ever be selected, and it is very easily found, for it exists in parts of all the districts discussed.
[CHAPTER V.]
NATURE OF JUNGLE.
I have not much to say under this head. I have heard many opinions as to the kind of trees and jungle that should exist in contemplated clearances, but I attach little or no weight to them, at all events in Bengal.
In the Himalayas it is somewhat different. There oak trees should be sought for; their existence invariably makes rich soil.[12] Fir, on the contrary, indicates poor soil. At elevations, however, the desideratum of a warm aspect interferes, for the best oak forests are on the colder side. I speak of course of elevations practicable, say three or four thousand feet; above this it is a waste of money to try and cultivate Tea.
In Bengal I do not think the nature of the jungle on land contemplated signifies much. As a rule, the thicker the jungle the richer the soil; but in seeking for a site large trees should not be a sine quâ non. Much of the coarse grass land is very good, and large trees add enormously to the expense of clearings.[13] It is not cutting them down which is so expensive, it is cutting them up and getting rid of them by burning, or otherwise, after the former is done.
I have discussed soil fully already, and need only add here that if the knowledge to do so exists, it is better to judge of soil from the soil itself than from the vegetation on it, though doubtless a fact that luxuriant vegetation indicates rich soil.