Vol. V. No. 120. 



THE AGRICULTUKAL NEWS. 



381 



SPIRAL METHOD OP TAPPING RUBBER 

 TREES. 



The fii'st sy.stematic arrange raont of the cuts in 

 tajjping is the V system, with one cup at the apex of 

 each V. By shaving the lower sides of the cuts the 

 yield may be jDrolonged for some time, about two 

 months cojitinuously. This s^-stem leaves the bark 

 rough when it heals, and the point of bark at the apex 

 of tTie V often loosens and dies. 



The second system is that known as the herrh:g-bone, 

 with a long vertical channel. The objection to the latter is 

 that it decreases the tension of the bark and so diminishes 

 the flow of latex. By shaving the lower side the yield may 

 be continued till the upper side has completely healed. 



The third system is the half-spiral wliich resembles the 

 half-herring-bone, except that the cuts (1 foot apart) are 

 carried half round the tree. There may be a vertical channel, 

 or a cup may be used for each cut. 



The full spiral method consists of two or more spiral cuts 

 winding round the tree, a foot apart, at an angle of about 4-5°. 

 This method is fully described in articles in the Tfopical 

 Agriculturist, 190-5, pp. 308, 547, and 641, It is also 

 compared with the other methods by Mr. Herbert Wright in 

 his book on Para Rubber, which was reviewed in the 

 Agricultural News, Vol. V, p. 2.57. The cuts are marked out 

 by a zinc stencil and the first incision is made with the 

 Bowman-North way knife No. 1, which resembles a plane, and 

 is so constructed that the operator can cease cutting deeper 

 when the light white colour of the cambial tissues is .seen. 

 Knife No. 2 is used for paring the lower edge of the cut, for 

 a fresh flow of latex. It is provided with a guard so as to 

 prevent any incision of the cambium and will cut a shaving 

 •y'jj- inch thick. It seems best to tap the trees on alternate 

 days. If 1 inch were removed every two months, it would 

 be two years before the lower edge of one spiral reached the 

 healed upper edge of the next. By the use of knife No. 3, 

 which has the form of a revolving wheel with sharp teeth, and 

 is used for opening the latex tubes without removing any 

 bark, the period may be prolonged to three years. 



A great advantage of this system is that it leaves no 

 untouched bark, and so, on healing, the stem is c^uite smooth 

 and the process may be repeated indefinitely. 



A drip-tin at the top of each spiral keeps the latex from 

 coagulating in the cuts. At Deviturai, Ceylon, 248 trees, 

 tapped by the V system, gave (in 1903) 240 ft), of rubber, the 

 usual yield by this method on this estate. In 190-3 the full 

 spiral system, applied by its inventor, resulted in a yield of 

 1,317 lb. being obtained from the same 248 trees. An 

 average yield of 16 tti. yearly was obtained by the spiral 

 method from trees about twelve years old, and the foliage, 

 seeds, and renewed bark, were perfectly healthy after tapping. 

 The large yield and the perfect renewal of bark more than 

 compensate for the exti'a labour required. 



At Flenaratgoda, Ceylon, twenty -five trees tapped on the 

 full spiral system, from September 1905 to February 1906, 

 gave 50,1 lb. of rubber ; twenty-five trees of the .same size, 

 tapped at the same time by the half spiral method, gave 

 35-J- R). of rubber, and twenty-five trees tapped on the full 

 herring-bone gave ^Ijs K). The total amount of bark 

 removed in the above experiment (full spiral) was only 

 1^ to 2 inches. At Peradeniya four trees, twenty-nine years 

 old, yielded 11 lb. 5-| oz. in three and a half months by 

 V cuts, though the yield fell off considerably. Four other 

 trees, twenty-nine years old, yielded in the same time by 

 spiral cuts 22 lb. 11 oz., and the yield did not fall off 

 so much. 



PREVENTION OP ANTHRAX IN 

 ST. VINCENT. 



The following is the substance of a notice recently 

 issued by the Government of St. Vincent: — • 



Persons owning or in charge of animals becoming sick 

 or dying, or which are found dead, who" are guilty of neglect 

 to report the deaths are liable to a fine not e.xceeding £100. 

 The police have strict orders to prosecute such persons, while 

 a reward of 5.s. will be paicl to any person who gives 

 information which results in the conviction of such persons. 



The present steps are taken by the Government purely 

 in the interest of stock-owners to arrest, as far as possible, 

 the disease of anthrax, and assist in opening the markets for 

 St. Vincent stock, and all persons interested in this are 

 invited to assist the Government by bringing to light any 

 breaches of the regulations, which are liable to do much harm. 



THE INFLUENCE OP VOLCANIC ASH 

 ON CROPS IN ST. VINCENT. 



In the last number of the Agricultural Netvs 

 (p. 359) reference was made to the value of volcanio 

 ash in the conservation of moisture in soils in the 

 Eastern Canaries. Mr. W. N. Sands, Agricultural 

 Superintendent in St. Vincent, has forwarded the 

 following notes on the influence of volcanic ash on 

 crops in that island : — 



As far as St. Vincent was concerned, the advantage of 

 the volcanic ash which fell during the last eruption was 

 practically nil, as, with the exception of sugar-cane and 

 leguminous crops, such as pigeon peas and ground nuts, no 

 other crop can be grown satisfactorily in it. Of course the 

 rainfall of the island is a heavy one, but even during two or 

 three weeks of dry weather plants suffer severely. 



Take for instance cacao. Oa the leeward side of the 

 island, in those districts where a large amount of ash fell, the 

 trees are producing little or nothing. They are much diseased 

 and present an unhealthy appearance generally. On the 

 windward side of the island, at Mount Bentinok estate, the 

 cacao trees are doing well, and this is due to the ash being 

 entirely taken from around the trees after the eruption. On 

 the leeward side the cacao trees were not treated in this way, 

 and on inspecting the fields of ilessrs. MacDonald Bros., at 

 Pdchmond Vale, it was seen that the ash from the first 

 eruption had set almost like concrete over the surface of the 

 original soil, killing, of course, a large proportion of the roots 

 near the surface; hence the bad condition of the trees. 



Cotton, again, is more or less a failure in volcanic ash. 

 Mr. Thornton and myself recently inspected large areas in the 

 Carib Country, and, as mentioned previously, only deep 

 cultivation and a system of mixing with the ash a large 

 quantity of organic matter, by means of manure and green 

 dressings, will bring back the lands to such a condition as 

 will enable crops like arrowroot and cotton to be successfully 

 grown. 



The growth of the pigeon pea planted thickl}-, and 

 buried in the ash just before it reaches the flowering stage, 

 would help con.siderably. This plant grows extremely well, 

 sends out a large number of roots into the ash, which, when 

 examined, are found to bear a large number of nodules. 



The planting of sugar-cane, which requires deep cultiva- 

 tion in order to produce a satisfactory crop, would also help, 

 but a system of green dressings of Jeguminous plants appears 

 to hold out most hope of .success in the reclamation of these 

 lands with a large proportion of ash and sand. 



