and Magazine of the Ceylon Agricultural Society.— Junt, 1910. 



560 



COCA CULTIVATION IN PERU. 



The bulk of the coca leaves of commerce are 

 obtained from Peru, with smaller amounts from 

 Bolivia, Java and Ceylon. In recent years, owing 

 to the increasing use of the drug, either as such, 

 or in the form of cocaine, the demand of coca 

 leaves in Peru has been so great that the natural 

 forests of coca bushes are beginning to show signs 

 of exhaustion, and attention is now being given 

 to the cultivation of the plant (Der Tropen- 

 flanzer, 1909, 10. 386). It grows in Peru at an 

 elevation of from 700 to 2,500 metres above sea 

 level, and requires a deep, fairly rich soil. In 

 forming a plantation the existing crop on the 

 land is cut and the debris from this piled in 

 heaps and burnt, the heat from the burning re- 

 fuse serving to destroy insect pests in the soil. 

 The plants are best raised from seeds sown in 

 nurseries. Coca seed keeps badly, and it is 

 advisable to use seed not more than eight days 

 old for sowing. The seed bed should consist of 

 good, well-worked soil, and the seeds should not 

 be deeply buried, but merely lightly covered 

 with a thin layer of soil. They should germi- 

 nate in about a fortnight, and should reach a 

 height of from 8 to 12 inches in about four or 

 five months, when they are ready for trans- 

 planting, the soil in the proposed plantation 

 should be well worked to a depth of about one 

 foot, and the seedlings planter 1 out at distances 

 of about 40 inches from each other, i. e. 40 inches 

 square should be allowed to each plant. The 

 plantation requires little care except occasional 

 weeding, but young plants in the nursery or 

 the plantation require shading from strong sun- 

 shine and protection from frost on cold nights. 

 Leaf collection should not begin till the plants 

 are two years old, bub to secure a return in 

 the first two years, maize or manioc (cassava) 

 may he taken as a catch crop between the 

 rows of coca plants. In collecting the leaves, 

 these should be roughly torn from the 

 branches, but should not be broken off, or 

 cut a little above the connection of the leaf 

 petiole with the branch. A well-grown plant 

 should yield annually from 5 to 10 lb. of leaves, 

 and should continue to yield for from tan to 

 twenty years, provided it is grown in good soil 

 and a suitable situation. The leaves should be 

 slowly dried in a shady place, frequent turning 

 being resorted to, to prevent sweating. 



The present value of Peruvian coca leaves is 

 about 5Jd. to 6d. per lb., but the carefully grown 

 and prepared Ceylon leaves fetch as much as 

 lOd to Is. per lb., or more, at the present time. 

 Since the natural supply of Peruvian leaves is 

 failing to some extent, there would appear to be 



AN OPENIISG FOR THE MODERATE KXPENSION 

 OF COCA- PLANTING IN CEYLON 



and the Federated Malay States, where the 

 plant has been found to do well already. In 

 forming plantations care should be taken to 

 secure seed of the Peruvian variety, the leaves 

 of which contain cocaine, and not that grown in 

 Java, which furnishes leaves containing little or 

 no cocaine, but only closely related alkaloids, 

 which hive to be converted into cocaine by a 

 chemical process after extraction. The Java 

 leaves, it should be noted, however, are richer 

 in "total alkaloid'' than the Peruvian sort. — 

 Imperial Imtitute Bulletin, Vol. VIII, No 1. 



RUBBER IN COCHIN AND 

 TRAVANCORE. 



[By the U. P. A. S. I Scientific Officer.] 

 Cultivation. — My views upon the system of 

 keeping rubber clean weeded have been ex- 

 pressed elsewhere. On many estates cultivated 

 under this system the annual loss of top soil is 

 enormous, and it will doubtless seriously affect 

 the life of the rubber. The rainfall on a typical 

 estate, for instance, during last year was in May 

 15'5 inches, in June 33 inches, and in July 33'6 

 inches. This heavy rain fell on bare soil which 

 had- been powdered all through the dry season 

 by constant mamotie weeding, and the conse- 

 quence was that tons and tons of the very best 

 top soil were washed away and laid over the 

 surface of surrounding paddy fields. The loss 

 and the evil are usually admitted, and in some 

 cases curious, and often expensive and cumber- 

 some, methods of mounds and trenches, &c.,are 

 adopted to try and stop the wash. The simpleet 

 method of all is to grow a green dressing instead 

 of weeds, and keep the soil covered. This will 

 not only stop the wash during the monsoon, but 

 it will add humus to the soil both from its own 

 material and by catching and holding the fallen 

 rubber leaves, which on many clean weeded 

 wind-swept estates are blown away and lost, and 

 all the dry season it will keep the soil shaded 

 and moist, bringing the soil water near the 

 surface where it is wanted. 



A Direct Experiment — showed on one estate 

 I visited that the soil under a covering of Passi- 

 flora contained in February, after three months 

 of dry hot weather, 11 per cent, more moisture 

 than the soil which had been kept bare and 

 clean weeded. The preservation of the top soil 

 and the constant addition of humus to it to 

 improve the mechanical condition are most 

 important points, and I am sure that no rubber 

 planter can afford to neglect them. In some 

 districts a thick cover of Erythrina is grown, 

 the branches being bent over so that the whole 

 soil is shaded, and covered with a thick layer of 

 mulch, while open spots are covered with a crop 

 of Passiflora or Crotalaria. Such estates are 

 quite as good as, in fact in one or two notable 

 instances much better than, estates which 

 have always been clean weeded. Erythrina will 

 not grow in all districts, possibly because 

 the necessary soil bacteria are not present. If 

 the soil in the holes in which the plants 

 are started was inoculated with a little 

 soil brought from an estate where Erythrina 

 is well established probably the difficulty 

 would be overcome. This, however, is hardly a 

 practical method, though it would form an inter- 

 esting experiment. In districts where Eryth- 

 rina will not grow, Albizzias should be tried, and 

 cut over in the same way as Erythrina, and more 

 use should be made throughout the whole of the 

 rubber districts of local leguminous plants like 

 the various indigenous Crotalarias, Cassia hirsuta, 

 Cassia mimosoides, Tephrosia tinctoria, Tephrosia 

 purpurea, &c. 



The starting-point for such green dressings is 

 a clean weeded estate. In a new clearing the 

 weeds should be got rid of as soon as possible by 

 rounds of weeding following one anothor in 

 quick succession so that the indigenous crop of 



