Some planters, when pruning, remove moss and rub down the trees at the same time, but this, I am sure, can be done more cheaply and effectually as a separate work.
The removal of moss and rough bark, and generally cleaning and rubbing down the trees is a work of very great importance, and should be carried out once every two or three years. The injury arising from moss is too well known to call for any remark, but the reason why the removal of rough bark, and especially rough bark at the head of the tree, and at the junction of the topmost branches with the stem is of such importance is, that it is in the crevices of the rough bark that the Borer fly lays its eggs. When thus removing the moss and rough bark, the eggs may often be destroyed, and in the absence of rough bark to shelter them, it is probable that the insect would probably not lay the eggs at all, or that, if it did, they would either become addled, or fall to the ground. I may add here that we have found a piece of square tin the best thing for scraping down the trees, and that the hair-like fibre of the sago palm is an excellent thing for rubbing down the stems.
Though moss thrives best in damp situations, and on northern aspects, it sometimes exists on open and eastern aspects, and, when the latter is the case, the moss is certainly due to poverty of soil, and in such cases, in addition to scraping the trees thoroughly, an application of top soil mixed with lime, or bonedust, should be applied to the land. I may add that I have seen trees on a dry knoll, and with no shade over head, covered with moss, and this was no doubt owing to poverty of soil, which caused the bark to be in an unhealthy condition, and therefore a suitable home for the growth and spread of moss.
Digging and working the soil in order to keep it in an open condition is of great importance, because, to use for the second or third time the words of Sir John Lawes, "it is the physical condition of the soil, its permeability to roots, its capacity for absorbing and radiating heat, and for absorbing and retaining water, that is more important than its strictly speaking chemical condition." In other words, a moderately fertile soil, if maintained in fine physical condition, will give better results than a rich one which is in a hardened state. But to keep the soil in good condition, and yet comply with the fruit cultivators' chief axiom that, "from the time of blossom till the crop is ripe the roots should not be disturbed," is a matter of great difficulty—I might almost indeed say an impossibility. For, from the trampling of the people in their passage up and down the lines, and the dash of the rain, the soil becomes exceedingly hard immediately after, or at least very shortly after the rain. Here, then, the planter finds himself between the devil and the deep sea. Is he to leave his soil in a hardened state from the beginning of November to the end of January, or perhaps the middle of February, or is he to violate the axiom which tells him not to disturb the roots till after the crop is ripened? And here I think the condition of things is such that he should come to a compromise, and dig up at the end of the monsoon a space of about 2 to 2½ feet up the centre of the lines, which, being the part always walked upon, is necessarily liable to be puddled and hardened, and then, after crop-picking is finished, lightly dig, or pick over and stir, the remainder of the soil, breaking, of course, all clods at the same time. By such a process we should prevent the central portion drying up and cracking, and aerate laterally the rest of the soil, and at the same time do as little damage as possible to the roots. I need hardly say that it is of great importance to begin with all those places where the soil is most hardened, as, should the planter not be able, from shortness of labour, to complete his digging before crop, he will at least have dug those places most urgently in need of cultivation. If the soil of the estate is pretty even in character, the hottest aspects will of course harden soonest, and should be dug first, but it may so happen that a hot aspect may have a soil of a loose and open character, while a north aspect might have a soil of stiff character, and here the planter must alter the rule so as to suit his particular case.
For digging, or rather loosening the soil at the end of the monsoon, my experience is that the four-pronged Assam fork is the best tool, and that for the light picking over of the whole of the soil after crop a light two-pronged digger is best. This last tool is shaped like a mamoty, but with two prongs rather widely set apart instead of the broad blade of the mamoty. It being very light, it can easily be turned in the hand, so that clods may be broken with the back of the tool, and it can be used by women, which of course is of great advantage for pushing forward the work.
Renovation pits, as they are called, were once regarded as an excellent means of deeply stirring the soil, but, of recent years, have fallen out of favour with many planters, and I think justly so. These pits, or rather trenches, are dug in the spaces between four trees, and are generally about fifteen inches in depth, as many in width, and about ten feet long. Weeds and rubbish were thrown into them, and when they were filled with these, and soil washed into them, the pits were abandoned and another set opened. I am now satisfied that these pits did much damage by the sub-soil—which is often of an undesirable quality, and always, of course, more liable to run together and harden than the original top soil—being thrown on to the surface of the land. In fact, they did the same damage that the steam plough has often done at home in unskilful hands, i.e., turned a fine loose surface soil into one of an inferior character. Then the sides and edges of the pits harden and crack, and this of course adds to the heat of the plantation. But renovation pits may be put to an excellent use if employed in their character of water-holes, as they are called by the natives, and whenever land is liable to wash, they are of great service, and, though but small portions of our shaded plantations are ever liable to wash, a line of renovation pits should always be put on the lower sides of roads to catch the water that runs off them, and thus cause it to soak gradually into the soil. When renovation pits are used as water-holes no new ones should be opened, but the old pit should be cleaned out and its contents scattered on the surface of the land, not between the rows of coffee, as the soil would at once run into the renovation pits below, but around the stems of the coffee trees and in the lines. I have found that renovation pits, or water-holes, are of great value as water conservators, and wherever it is necessary to increase the supply of water for a tank, deep water-holes—say from 3 to 4 feet in depth and width—should be dug around the upper sides of the tank, and the rain water conducted into them by small channels. We have found, on my property, such an appreciable effect from even a moderate amount of such holes, that I am now largely increasing their number. A friend of mine has also found a similar effect in connection with his tank, though, I may mention, he had made the pits in connection with his coffee, and not with the view of increasing the water supply in his tank. I believe that this method of increasing the water supply would be well worth the attention of Government in connection with its numerous tanks.
The reader will remember that I have recommended applications of jungle top soil and other soil, and it should be remembered that such applications will, by rendering the soil more open, much lighten the work of digging, and this is a point that should be carefully estimated when calculating the expense of dressing the land with fresh soil.