228 



THE AGRICULTURAL NEWS 



July 15, L916. 



ORCHARD CULTIVAHON. 



THE BAY TREE AS A CROP PLANT. 



lu llic last issue but oue of the Ayricnltiiral Xetvs 

 appeared a summary of the first half of. a paper in the current 

 issue of the West Indian Bulletiv, on bay oil and the cultiva- 

 tion of the bay tree as a crop plant. The summary referred 

 to dealt principally with the metljod of establishing a 

 plantation of bay trees and with the composition of bay oil. 

 The Bulletin article referred to, concludes with an :iccouut of 

 the results obtained from experiments connected with the 

 distillation of the oil from the leaves. 



Monthly reapings of leaves from the experimental area in 

 Montserrat were distilled separately, and the resulting oil exam- 

 ined. This work was conducted over a period of three years. 

 A survey of the results shows the relatively greater variation 

 •which occurs in the composition of the oil from the trees on 

 the plot, while the yield of oil per 1001b. of leaves is 

 also found to vary within wide limits. No very close 

 connexion was observable between the yield of oil and the 

 season of the year at which the distillations are conducted, 

 nor is the connexion between the season of the year at which 

 the distillations are performed and the composition of the 

 resulting oil particularly obvious, although there is some 

 indication that leaves reaped between the months of -March 

 and August give oils with a higher phenol content than do 

 those at most other seasons of the year. This may perhaps 

 be interpreted as indicating that the best results are obtained 

 in the dry seasons of the year. Distillations conducted during 

 the year 1915, and not included in these results, further 

 strongly confirm this idea. 



It is to be remarked that the yield of oil per 1001b. 

 of leaves shows a progre.s.sive increase as each year (!liipses,and 

 the inference seems to be that the oil content of the leaves 

 tends to get greater as the trees approach maturity, although 

 the result in question is partly due to increas(;d care in 

 reaping, which has insured that none but mature leaves are 

 gathered. 



As the outcome of the above results, the question arose 

 as to whether much variation is experienced in the yield and 

 quality in the oil obtained from individual trees. An inves- 

 tigation indicated that considerable variation both in yield 

 and composition occurs in the case of individual trees, and 

 it would appear that the selection of trees for obtaining seed 

 for planting purpo.ses on the basis of a satisfactory yield of 

 oil of good quality is likely to be productive of good results. 



Another point which was made the subject of investiga- 

 tion was the prognssive variation of the composition of the re- 

 sulting oil as the act of distillation j)roceeds, cornbint'd with an 

 attempt to a.scerlain the length of time for which it is profit- 

 able to continue distilling. It was found that the volume of the 

 oil distilled per hour diminishes rapidly after the first hour: of 

 the total amount collected, about half comes over during that 

 period, the remaining fraction gradually diminishing in 

 volume until the ninth hour is reached. An important result 

 arrived at was that the phenol content increases up to the 

 eighth hour. Formerly it was customary in the Montserrat 

 experiments to stop the distillation at the end of the sixth 

 hour, but in view of the fact that the value of bay oil 

 depends largely upon its phenol content, it is important to 

 ascertain what the effect on the phenol content is of the 

 small amount of oil distilling over in the last three hours 

 not included hitherto, it was found that when the first to 

 the sixth fractions are mixed, the resulting mixture has 

 a phenol content of 54 per cent.; while when the seventh and 

 eighth fractions are included, the mixture shows a phenol 

 content of 58 per cent. 



Other points dealt with in the paper referred to, include 

 the desirability of using sea-water in the still in the place of 

 fresh water; the keeping qualities of bay oil; and lastly the 

 action of bay oil on thp metal of the still. It was found 

 that there is no advantage in using salt-water, although it 

 is favoured in St. Thomas and St. Jan. As regards keeping 

 qualities, the oil will keep unchanged as regards phenol 

 content for upwards of three years, but polymerization of the 

 myrcene occurs, producing waxy solid.? or heavy oily liquids. 

 In regard to the eftect of the oil on metal, it was found that 

 lead must never be used, and that the best metal is copper. 



NOTES ON COCO-NUTS IN DIFFERENT 

 COUNTRIES. 



These notes appqar in the current issue of the 

 Bulletin of the Imperial I-nstiliite (^'ol. XIV, No. 1), 

 and give a good idea of recent pi-ogress in coco-nut 

 cultivation in different part.s of the tropics: — 



At Batticaloa, the centre of the coco-nut cultivation in 

 the Eastern Province of Ceylon, the average annual rainfall is 

 nearly 6.'? inches, but 50 inches of this falls during the 

 North-east monsoon from October to February; owing to this 

 uneven distribution of the rainfall the palms only bear small 

 crops {Tropical A<jricxdh(rist, 1914, 45, 293). The trees are 

 planted eighty to an ac:e, and bear, on an average, twenty-five 

 nuts per tree a year: it is suggested that con.servation of soil 

 moisture by removal of weeds and disc-harrowing once 

 a month would increase the yield. The soil is sandy and 

 suitable for coco-nuts, although lacking in humus. The 

 waste husks should be returned to the soil instead of being 

 burned, and jungle mulch should be applied wherever this is 

 easily obtainable. Green manures are recommended for 

 young plantations, divi-divi being particularly suitable. 



Coco-nut planting has made good pi-ogress in the Gold 

 Coast (Jolony, but at present copra is produced almost exclu- 

 sively in the Quittah and Addah districts of the Eastern 

 Province {Rep, Agric. Dcpt., GtAA Coast, 1914, pp. 10, 16). 



Coco-nuts planted at the Assuansti Experiment Station 

 in the Central Province are making very satisfactory growth, 

 and palms planted in 1910 flowered in 1914. Rhinoceros 

 beetles have been troublesome on the plantation, but no tr-ees 

 have been destroyed. 



In Brazil coco-nut palms are frequently attacked by 

 a bacterial disease similar to that which has been ascribed to 

 Bacillus ciili, and some trees have been destroyed (BoUtin, da 

 Arjrindture, Sao Paulo, 1915, No. 5, p. 4.35). It appears 

 that certain insects cause damage which aids in the spread of 

 the disease, and of these Amerr/timi.t payilherinus is the most 

 important; the larvae excavate galleries in the leaf petioles, 

 thus causing the death of the leaves; destruction of the parts 

 attacked is the only remedy. The larvae of Alurnus mir- 

 (jina'ii?, Guer., also attack the leaves: spraying with insecti- 

 cides has been found useful for the control of this pest. 



The larvae of a moth {Castiiia daedalus) wei-e reported 

 a few years ago as causing damage to coconut palms in 

 British Guiana (cf. this Bulletin, 1914, Vl, 305). The inssect 

 has since been found to be very abundant in .some dis- 

 tricts, and according to the Government Economic Biologist, 

 it is the worst pest which has hiiiierto attacked the coco-nut 

 palm in the colony, and it is considered that, unless its 

 ravages are cheeked, coco-nut cultivation will cease to be 

 profitable {Rep. Depl. Set. ami Agric, British Guiana, 

 1913-14, App. Ill, p. 7). The enacment of a Plant Pro- 

 tection Ordinance is regarded as desirable for the purpose 

 of eradicating this and other iwsts. 



