280 



THE AGRICULTURAL NEWS. 



September 2, 1911. 



EDITORIAL NOTICES. 



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 specimens fur namitio;, should be addressed to the 

 Commissioner, Imperial Department of Agiiculture, 

 Barbados. 



All applications for Copies of the 'Agricultural 

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Local Agents: Messrs. Bowen & Sons, Bridge- 

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 will be found on page .3 of the cover. 



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 post free 2d. Annual subscription payable to Agents, 

 2s. 2d. Post free, is. 4cZ. 



The West Indies in Canada, 1911. 



As was stated in a former issue of the Agricul- 

 tural Aeivs (No. 235), the illustrated booklet entitled 

 ' The Wesr, Indies in Canada, 1911 , has been published 

 for the Canadian National E.\hibition that is being 

 held in Toronto at the present time. 



The booklet presenis the same features as those of 

 the liist edition, and the statistical ducails have under- 

 gone the necessary revision. The illustrated portion 

 was printed on calendered paper, as in that edition, on 

 account of the nnprovement that has been effected by 

 the u.se of superior paper for the half-ione illustrations. 



Sloriciiltural Beiu.'i 



Vol. X. SATURDAY. SEPTEMBER 2, 1911. No. 244. 



g ■ ' - ■ ■ ■—-■ ■ — ■ ' ^ "'~ 



NOTES AND COMMENTS. 



Contents of Pi esent Issue. 



In this number the editorial deals with Light and 

 the Growth of Trees. This is a subject that is possibly 

 of more importance in temperate climates than in the 

 tropics, on account of the smaller intensity of illumina- 

 tion in those latitudes. It deserves study, nevertheless, 

 in the tropics, because of its importance in relation 

 to the growing of trees collectively, in plantations, and 

 to the provision of shade plants and trees. 



Under the heading Sugar Industry, on page 27.5, 

 information is given concerning the production of sugar 

 in Cuba, in 1910. 



An account of interesting trials of green dressings 

 that have been madi^ recently in Dominica is presented 

 on pa^e 277. Similar experiments, undertaken in St. 

 Lucia, receive attention in this number of the Agri- 

 cultural Ncti's, on page 284, and more particularly in 

 number 242 of the present volume. 



On piige 279 there appears an abstract of a useful 

 'article, concerning the coMgulatioii of rubber latex with 

 acetic acid. 



The Insect Notes, in this issue, present ;ui illus- 

 trated article on the mango weevil (Urijptorhijnchus 

 inangiferae I. 



An article entitled Manuring and Jleat I'loduction 

 is given on page 288. This presents the conclusions of 

 ■work, in relation to the subject, that has been conducted 

 continuously, through a long period of years. 



Periodicity in Yield of Plantation Crops. 



Ubservations made fur the purpose of regulating 

 the times and e.xtent of tapping, on rubber estates, have 

 drawn attention to the expected fact that the yields of 

 such crops do not remain constant throughouD the j'ear, 

 but vaiy in relation to different conditions. In the 

 In diji- Rubber Journal, \'ol. XLI, No. 12, p. 16, the 

 subject is considered at some length, in an article, where 

 it is pointed out, firstly, that while in most parts of 

 Malaya, where the climatic conditions remain virtually 

 the same throughout the year, the monthly returns 

 from the trees are fairly constant, the macter is very 

 different in the ca?e of those pans of (_'eylon where 

 Hevca is grown, and where there is a marked dry period 

 from January to April. In the latter case, during this 

 period, the yield of latex, as well as that of dry rubber, 

 IS smaller, per tapping. The figures that are available 

 short' that this is not the case in regard to the second, 

 smaller dry season; this is probably because of the 

 increase in age of the trees, and in that of the number 

 which is being tapped. 



Interesting figures relating lo rubber production 

 in Ceylon arc givea, which support the contention that 

 the advent of the dry season causes a reduction in out- 

 put from the trees. The conclusions from these are 

 complicated by the fact that heavy rains interfere with 

 tapping operations to such an extent as to decrease the 

 output during the time that these ai"e being received. 



It is pointed out that, even in Malaya where, as 

 has been said, the variations in the climate during the 

 year are smaller than in Ceylon, there is a decrease in 

 tlu- amount of t>i}ipiug during Febriuxry and March 

 because it is believed that the trees, while losing their 

 old leaves and producing new foliage, give a smaller 

 yield of latex and receive benefit from a rest. This is 

 probably true, on account of the decreased tnrgidity of 

 the cells, owing to the lessened transpiration through 

 the loss of the old leaves. A further cause of irregular- 

 ity is ihe rajiid increase in tr.uispiration on account of 

 the appearance of the young k-aves. 



The m.atteis coiisi<lerod in the article give rise to 

 the conclusion that, when the Hevea trees growing in 

 the East have reached maturity, there will always be 

 a decline in the rubber exports from th.it jiart of the 

 world during February and .March, and this notwith- 

 standing the custom of regular tapjjing which has been 

 adopted on th(> inHJority of the estates. 



