Vol. XVIII. No. 449, 



THE AGRICULTURAL NEWS. 



215 



revolving beater drums mounted on a shaft which rota'es 

 in the opposite direction to the drum. In the fifth 

 process, the fibre is spread out in the sun to dry, 

 which in fair weather can be done in a day. Lastly, the 

 fibre is hydraulically pressed into bales measuring 20 inches 

 X 20 inches X 40 inches, which weigh about 180 tt). 



Regarding the commercial prospects before the manu- 

 facture of coco-nut fibre, it is the opinion of Mr. Neil of 

 Trinidad, that these are not promising, owing to the increased 

 cost of manufacture, and the rapidly falling prices obtainable. 

 The increased cost of manufacture is due to the high cost of 

 fuel oil and excessive freight rates. It is stated that the 

 cost of freight now amounts to one-third of the gross value of 

 the fibre shipped. It is possible, in the case of Jamaica, 

 that the cost of freight will not be so high an iteni of expen- 

 diture as it is in the case of Triniditd. At any rate, on the 

 basis of the information available, the production of coco nut 

 fibre in Trinidad is not regarded, under present conditions, as 

 a very profitable undertaking. 



For those readers of the Agricultitral News who wish 

 farther information principally in connexion with the coco- 

 nut as a source of fibre, and a description of the machines 

 used to extract the fibre and the oil, the following references 

 may be useful. Valuable information will be found in the 

 Coco-nut number of the Philippine Agricultural Review for 

 May 1912, and in a more recent one for the first quarter, 

 1918. Reference may also be made to the standard work 

 on the coco-nut by Professor Copeland. It is interesting to 

 learn from this book, for example, that certain varieties of 

 the coco-nut are more valuable than others for the manufac- 

 ture of fibre, and further, that there is a proper 

 time for the harvesting of the crop for this purpose, 

 before which, and after which, the coir is less in 

 quantity and less valuable, weigbt for weight. What the 

 time is can not be stated definitely, but it may be roughly 

 said to be at the beginning of the ripening of the nut. It 

 may be at the time when the nut as a whole is largest, 

 or may be a little later than this, but is certainly consider- 

 ably before the time when the nut should be harvested to 

 get the greatest and best yield of copra. 



Turning to the matter of coconut oil production, the 

 Imperial Commissioner of Agriculture has called attention 

 to the possibilities in this direction of the Anderson Oil 

 Expeller. One of these machines is in successful operation 

 in St. Vincent, for the manufacture of cotton-aeed oil. An 

 account of this machine and of its cost is contained in the 

 West Indian Bulletin (Vol. XV, pp. 306-8). Sir Francis 

 Watts has had a small preliminary trial made of this 

 machine with coco-nut material, and the results appear 

 promising. 



In conclusion, the production of coco-nut fibre and oil 

 is to be encouraged, even though at the present time labour, 

 freights, and fuel may be temporarily inflated. Particularly 

 in the case of fibre has there been a great deal of waste in 

 the West Indies ever since the beginning of coconut 

 culture on an organized scale- 



THE SHEDDING OF ORANGES. 



Although seriou^s trouble in regard to the shed- 

 ding of oranges does not appear to have been re- 

 ported in the West Indies, the following account 

 of abnormal shedding of the Washington Navel 

 orange in California will prove interesting to local 



growers. It may be noted that) abnormal shedding 

 has been reported in the case of coco- nuts, and the 

 flowers of .some citrus trees in the West Indies. This, 

 like the California trouble, is caused by a fungus 

 intensified by conditions of environment :— 



Citrus trees, as grown in the interior valleys of ths 

 and south-west, are subject to an environment entirely 

 abnormal to them in their natural habitat. Moreover, the 

 principal variety grown in these regions, the Washington 

 Navel orange, is itself decidedly erratic and unstable. 



Among other troubles incident to the abnormal climatic 

 conditions is tljat heavy dropping of the young fruits, with 

 consequent light crops, known popularly as the June drop 

 A study of the shedding has established the fact that it 

 constitutes true abscission, involving the separation of livinK 

 cells along the plane of the middle lamellae. Exhaustive 

 investigations a.s to the stimulus or stimuli responsible for 

 the abscission have narrowed them down to two : a fungus 

 Alternaria citri, E. and P., and climatic conditions. 



It is considered highly probable that a certain varying 

 per cent, of the drop, occurring relatively late in the season 

 IS brought about by the stimulation of this fungus, which 

 18 also responsible for a black rot of those infected fruits 

 which remain on the trees to maturity. 



This fungus is of very wide distribution, and infection of the 

 young fruits is made possible through the peculiar structure 

 of the navel orange. The amount of infection is dependent 

 upon weather conditions, anJ the more or less fortuitous 

 configuration of the navel end of the young fruits. 



On account of the peculiar manner of infection, and the 

 relatively small amount of shedding due to the fungus, spray- 

 ing will probably not | ay for the labour and materials 

 involved 



By far the greater part of the shedding, which occurs 

 earlier in the season, is due to a stimulus to abscission 

 arising from daily water deficits in the young developing 

 fruits, resulting from the asperity of the climatic complex to 

 which the trees are subject. 



The principal factor in causing these abnormal water 

 deficits lies in the fact that citrus trees are not adapted to 

 withstanding the heavy water loss incident to the desert 

 conditions under which they are grown. The amplitude of 

 stomatal movement is small, and cuticular transpiration very 

 high. It is further believed that under the prevalent clean 

 cultivation practised, the soil temperatures during a part of the 

 day are so high as to result in the inhibition of absorption at 

 the very time of day that water loss by transpiration is 

 greatest. 



It has been found possible to modify climatic conditions 

 in an orchard so as to set crops in every way comparable with 

 those produced in much more climatically favoured citrus 

 districts. 



Under these modified climatic conditions, the abnormal 

 water relations referred to apparently do not occur. 



Practical means of amelioration lie in heavier and more 

 frequent irrigation, the planting of intercrops, mulching with 

 straw and other materials, protection by means of wind-breaks, 

 and a reduction of leaf area by moderate winter pruning.' 

 Measures of an anticipatory nature lie iu the judicious 

 selection of the site lor the orchard, with r^-ference t > its 

 exposure, nearness to large irrigated bodies of land, and other 

 features calculated to ameliorate climatic ronditions. 



Orchardists should be on the lookout for mutant strains 

 which are dry heat resistant, and satisfactory in other features. 

 (University of California Publications in Agricultural 

 Science, Vol. Ill, No. II, pp. 283-368.) 



