The residue from the press cake is rich in nitrogen and humus, which, in the ever-increasing shade of the grove, will become more and more difficult to produce there through nitrogen-making agencies; but the waste from the manufacture of coir and the ashes from the woody sh.e.l.l will go far toward supplying the needed potash.
Such a system would, if closely followed, practically restrict the farmer"s ultimate purchases to a small quant.i.ty of acid phosphates, or of bone dust, which, in conjunction with good tillage, should serve to maintain the grove in a highly productive condition for an indefinite term of years.
IRRIGATION.
As an auxiliary manurial agent of definite, well-proven value in this Archipelago, I will briefly recite some of the benefits that may be expected to follow occasional irrigation during the dry season.
It strongly accelerates growth and early maturity. A few irrigated trees, reputed to be under five years from seed and already bearing fruit, were shown the writer on the Island of Jolo. The growth was remarkably strong and vigorous, notwithstanding that the water of irrigation had been applied in such a way that the tree could only hope to derive a minimum of benefit from its application. It had merely been turned on from a convenient ditch whenever the soil seemed baked and dry, at intervals of one to three weeks, as circ.u.mstances seemed to require.
Irrigation, but always in connection with subsequent cultivation, may be considered equal to a crop guaranty that is not afforded so effectually by any purely cultural system.
Rarely has a better opportunity occurred to demonstrate the unquestioned benefits that have inured to these few Jolo trees from the use of irrigating waters than the present season of 1902-3. From many sources reports come to this Bureau of trees failing, or dying outright, from lack of moisture. While it is true that the present dry season has had no parallel since 1885-86, and that the rainfall during the dry season has been less than half the normal, yet it should not be forgotten that, during the eight months from October to May, inclusive, the average precipitation on the west coast, at the lat.i.tude of Manila, is only about 460 mm. and that, when the amount falls below this, the cocoanut is bound to suffer.
Though it is true that the evil effects of drought may be modified, if not altogether controlled, by cultivation, the a.s.sistance of irrigation places the cultivator in an impregnable position. If evidence in support of this statement were called for, it might be found to-day in the deplorable condition of those groves that have been permitted to run to pasture, as compared with those in which some attempts have been made to bolo out the encroaching weeds and gra.s.ses.
It is probably true that, except on very sandy soils, continued surface irrigation would aggravate the superficial root-developing tendency of the tree; and to what extent, if any, occasional laceration by deep shovel tooth cultivation would injure the tree remains to be seen. There are, however, few economic plants that so quickly repair root damage as the Palmae, and, unless the seat of injury extends over a very large area, it is probable that the resulting injury would be of no consequence, as compared with the general benefits that would result from irrigation.
HARVEST.
Harvest of the crop requires but a brief discussion. The nuts should be plucked when ripe. The phenomenon of maturity can not be readily described in print. It frequently is as evident in nuts of a bright green color as in those of a golden-yellow color, and the recognition is one of those things that can only be learned by experience.
The practice, so general in the Seych.e.l.les, of allowing the nut to hang till it falls to the ground is certainly undesirable in these Islands. On the contrary, the overripe nuts will seldom fall until dislodged by a storm, and it is no uncommon thing to see nuts that have sprouted and started to grow upon trees in plantations where the harvest is left to the action of natural causes. Such nuts, of course, are entirely worthless for the manufacture of oil or copra, and even the husk has depreciated in value, the finest coirs, in fact, being derived only from the fruits that have not attained full ripeness. In any case, the nuts should be picked and the crop worked up before any considerable enlargement or swelling of the embryo occurs. From this time onward physiological changes arise which injuriously affect the quant.i.ty and quality of what is called the meat.
The heaping up of the nuts for some time after harvest favors some milk absorption, which seems to facilitate the subsequent easy extraction of the endosperm.
ENEMIES.
Outside of certain insects of the order Coleoptera, cocoanuts in the Philippines are reasonably free from enemies; in some districts, close to forest-clad areas, the raids of monkeys do some damage. A tree-nesting rat, which nibbles the young nuts, is also a source of considerable loss. The rat is best overcome by frequent disturbance of his quarters. This involves the removal of the dead leaves and thatch that form constantly about the base of the crown. But the wisdom of this recommendation will depend entirely upon circ.u.mstances. As the planter may find that rats or the rhinoceros beetle are the lesser evil, so should he be governed.
There are localities in the Archipelago where the plague of rats is unknown and where the beetles abound. In that case it would be unwise to disturb the leaves which are very tardily deciduous and do not naturally fall till the wood beneath is hard, mature, and practically impervious to the attacks of insects.
Where rats are numerous and insects few, which is the case in some localities, the dead and dying leaves, among which the rat nests, may be advantageously cleared away whenever the tree is climbed to harvest the fruit.
Among serious insect enemies we have to contend largely with the very obnoxious black beetle, Oryctes rhinocerus, and, fortunately, to a lesser extent, with Rhynchoporus ferrugineous (probably the same as R. ochreatus of Eydoux), while R. pascha, Boehm, and Chalcosma atlas, Linn., are also said to appear occasionally.
However different their mode of attack, the general result is the same, and their presence may surely be detected by the appearance of deformed or badly misshapen or lacerated leaves.
The attacks of all species are confined to the growing point and as far downward as the wood is tender and susceptible to the action of their powerful mandibles.
The black beetle makes its attacks when fully mature, eating its way into the soft tissues and generally selecting the axil of a young leaf as the point of least resistance. Others simply deposit their eggs, which hatch out, and the resulting grub is provided with jaws powerful enough to do the same mischief. Two or three of these grubs, if undisturbed, are sufficient in time to completely riddle the growing tip, which then falls over and the tree necessarily dies.
REMEDIES.
Remedies may be described as preventive and aggressive, and, by an active campaign of precaution, many subsequent remedial applications can be avoided.
Most of the beetles attacking the palm are known to select heaps of decomposing rubbish and manure as their favorite (if not necessary) breeding places, and it is obviously of importance to break up and destroy such; nor can any better or more advantageous way of effecting this be suggested than by promptly spreading and plowing under all such acc.u.mulations as fast as they are made; or, if this be impracticable, by forking or turning over or otherwise disturbing the heaps, until convenient to dispose of them as first suggested.
A truly preventive and simple remedy, and one that I can commend as a result of close observation, is the application of a handful or two of sharp, coa.r.s.e, clean sand in the axillae of the young leaves. The native practice is to mix this with ashes, salt, or tobacco dust; but it is questionable if the efficacy of the remedy lies so much in these additions as in the purely mechanical effect of the sand, the constant attrition of which can not be other than highly objectionable to the insect while burrowing.
Of offensive remedies, probing with a stout hooked wire is the only form of warfare carried on in these Islands; but, as the channel of the borer is sometimes tortuous and deep, this is not always effective. A certain, simple, and easily applied remedy may be found in carbon bisulphid. It could be applied in the holes (which invariably trend downward) with a small metal syringe. The hole should be sealed immediately with a pinch of stiff, moist clay.
It is likely that this remedy and probing with a wire are the only successful ways of combatting the red beetle, whose grub strikes in wherever it finds a soft spot; but, for these species which attack the axils of the leaves, I have great faith in the efficacy of the "sand cure," and no nut picker should go aloft unprovided with a small bamboo tube of dry, sifted sand, to protect the bases of recently expanded leaves.
In Selangor cocoanut trees now come under the government inspection, and planters and owners, under penalties, are compelled to destroy these pests. Mr. L. C. Brown, of Kuala Lampur, in that State, who writes intelligently on this subject, [8] lays great stress on the value of clean cultivation in subduing beetles, and repeats a cultural axiom that never grows old and that will, consequently, bear reiteration here--that it is rarely anything but the neglected plantation that suffers, and that the maintenance at all times of a healthy, vigorous growth is in itself almost a guaranty of immunity from attacks of these pernicious insects.
While we, unfortunately, know that this is not in all cases an a.s.sured protection against diseases or insect enemies, it certainly minimizes the danger and, in itself, is a justification of the high-pressure cultural treatment advocated throughout the preceding pages.
RENOVATION OF OLD GROVES.
Material improvement of old plantations may sometimes be effected and, unless the trees are known to be upward of fifty years old, generally repays the labor. Marked increase in crop has followed a heavy thinning out of trees upon the Government cocoanut farm at San Ramon, Mindanao. The improvement that a freer circulation of air and abundant sunlight have effected is very marked. Where it can be done, plowing is also sometimes feasible and should be followed by immediate crop improvement. The average native plow is not so well adapted for working over an old or neglected grove as it is for original soil preparation. It acts more as a subsoiler and will tear and lacerate more roots than is desirable. A single carabao, or one-horse American garden plow, is the better implement for this work. Extensive bat guano deposits are found in Mindoro, Guimaras, and Luzon. Some of them show richness in nitrogen and, when accessible at a moderate cost, would be useful in the renovation of old groves, where the shade would be adverse to the rearing of good crops of nitrogen gatherers.
CONCLUSION.
1. There are large areas throughout the littoral valleys of the Archipelago, as yet unexploited, which, in the essentials of soil, climate, irrigation facilities, and general environment are suitable for cocoanut growing.
2. The present conditions present especially flattering attractions to cocoanut growers capable of undertaking the cultivation upon a scale of some magnitude. By cooperation, small estates could combine in the common ownership of machinery, whereby the products of the grove could be converted into more profitable substances than copra.
3. The present production of copra (estimated at 278,000 piculs in 1902) is an a.s.surance of a sufficient supply to warrant the erection of a high-cla.s.s modern plant for the manufacture of the ultimate (the "b.u.t.ter") products of the nut. The products of such an enterprise would be increased by the certainty of a local market in the Philippines for some part of the output. The average market value of the best grades of copra in the Ma.r.s.eilles market is $54.40, gold, per English ton. The jobbing value on January 1 of this year, of the refined products, were, for each ton of copra:
b.u.t.ter fats $90.00 Residual soap oils 21.00 Press cake 5.20 ------ Total 116.20