Vol. XV. No. 374. 



THE AGltlUULTUKAL NEWS. 



283 



In ilarch and April 191.5, apparentl)' ripe oranges were 

 found on the ground infected by ihe caterpillar of Tortrix 

 citrana, Fern., observed in Brazil t'ur the first time, though it 

 is Avell known in California. A minute hole is made in the 

 fruit, usually in the lower portion, and the insect enters, its 

 presence being revealed by the expelled excreta which covers 

 the orifice. The caterpillar grows and bores into the orange, 

 which ripens and falls. In most cases the caterpillar carries 

 the spores of the fungus Ai'pergiUus pennictlium, with 

 which it infects the fruits. When full-grown, the caterpil- 

 lars pupate among dried leaves in civities of the trunk; the 

 moth emerges in three weeks. These habits are very similar 

 to those of the undetermined Tortrix. in Dominica. In the 

 case of the Dominica pest, the moth emerges in about two 

 weeks instead of three weeks later, as in Brazil. 



The collection and destruction by burying of all infested 

 fruit, whether lying on the ground or in the tree, is put 

 forward as the best method of control. In Dominica, the 

 most successful remedy appears to be the use of arsenate of 

 lead fis a spray early in the season, in order that the newly 

 hatched caterpillars may be poisoned as they attempt to eat 

 their way through the orange skin. 



MEXICAN METHODS OF TAPPING 



CASTILLO A. 



Ill the West Indian islands tiie Castilloa tree has 

 uot proved itself a satisf'actoi-y producer of'rublier. The 

 tree itself flourishes, but it has been found that repeated 

 tappings result in decreased yields. Possibly the 

 methods of tapping employed may have been partly 

 responsible for this; in any case the following statement 

 of the methods used in Me.xico, the native home of the 

 tree, by Mr. Ashinore Russan, will doubtless interest 

 those who have had pratical experience in the West 

 Indies with this rubber: — 



Previously to 1 903 the only tapping tool employed was 

 the machete, a kind of svvord or sabre, with a blade about 

 3 feet long, used for all kinds of agricultural purposes, such 

 as chopping down trees, clearing undergrowth, making 

 hillocks and holes for planting rubber .seeds and seedlings, 

 and for purposes of otfence, as killing snakes, ?nd, inciden- 

 tally, men. A really sharp machete was, and is, rather 

 a rarity, consequently the result of tapping Castilloa rubber 

 trees with it was murderous. Great gashes were inflicted — 

 anywhere, at all angles, anyhow. The deeper the cut 

 the more late.x — or so the Indian tapper appeared to 

 think — and in consecjuence there are now practically no 

 wild Castilloa rubber trees of tuppable size to be found in 

 Mexico, except perhaps in some dense and almost impene- 

 trable forest. One would think that the murderous machete 

 would never be used in plantations, but in 1900 and later 

 it was the only tapping tool employed on all the estates 

 I have mentioned, and on two or more of the estates the 

 older trees are suffering now from its use. As to Esmeralda, 

 it would have made little dift'erence if the trees had been 

 tapped with woodmen's axes. The Castilloas there, if any 

 are still alive, merely cumber the ground. 



Some ten years ago a tapping knife was evolved, I 

 believe, on the La Zacualpa estate which is still in use. 

 There are varieties and perhaps iniproveinents, but all are 



much alike, and the jirinciple of all is the same. The depth 

 of the cut can be regulated from about ^--in>;h upw.irds; the 

 width of the cut is about }-inch. I have personally tried 

 almost all kinds of tap[)ing knives on Castilloa rubber trees, 

 but only one, in addition to the knife now referred to, was 

 of any utility. The exception I refer to was an exhibit 

 at the Rubber Exhibition held at the Agricultural Hall. 

 The name of the inventor or originator has escaped me, 

 but he came from Mexico, and I tried his knife on 

 some Castilloa rubber trees at that Exhibition. It may be 

 remembered as having a handle like that of a .saw, and as 

 running on wheels. It did the work, but was not nearly so 

 simple and eft'ective as the knife which is in use today on 

 the largest estates in Mexico, The latter is rather a murder- 

 ous looking implement, but it must be remembered that the 

 delicate tools used for tapping Heveas are of no use whatever 

 for tapping Castilloas, the reason, I understand, being that 

 the latex cells of the Castilloa are long and vertical, one 

 transverse sloping cu*; completely draining some 4 to 6 or more 

 inches above it, while the Hevea latex cells are more like 

 a honeycomb, in which the slightest paring of the bark 

 should open up fresh cells. All Hevea tapping tools that I 

 ha%'e ever seen are useless for Castilloa. I have tried triangle- 

 shaped tools which would cut sufficiently deep, but the 

 waste bark choked them up at once. Any Castilloa tool 

 must have a free vent, with the cutting edges of the blade 

 nearly i-inch apart. It must also have an extra blade for 

 opening the cut. Such a knife makes a great gash in the 

 tree nearly as wide as one's finger, but that would appear to 

 be necessary, as Castilloa latex at certain times of the year 

 would not flow readily, and has to be wiped out of the cut 

 with the forefinger of the tapper. The depth of the cut can 

 be regulated according to the age of the tree and consequent 

 thickne.ss of the bark, and this matter should be carefully 

 attended to by the foreman or 'caporal' of the tappers before 

 startini; out; but the Mexican Indian tapper is both indepen- 

 dent and insubordinate, and no doubt often cuts a young 

 thin-barkeil tree just as deeply as he would an older thicker- 

 barked one. I have seen prickers and hammer chisels used 

 for tapping Castilloas, but they were not effective, and, so far 

 as I know, the knife described, or others on the same prin- 

 ciple, has not been improved upon, and is not likely to be. 

 (From 'he Tratisa''.tioiu of the Third Internitionil Congress 

 of Tropical Agrirulture, 1914.) 



It was mentioned in the previous annual report on the 

 Department of Science and Agriculture of British Guiana 

 (1913-14) that two beds of Ginger Lily {Hedychium coroiia- 

 rium) had been planted and that two crops, one plant and 

 one ratoon crop, had been reaped within a year, giving 

 a return of green stems and leaves equivalent re.spectively to 

 22 and 27 tons per acre. A second ratoon crop reaped 

 during the year under review (1914-15) gave a return 

 equivalent to 20 tons (ler acre The total return for three 

 crops was, therefore, equivalent to 69 tons of green material 

 per acre. Keducing thi^ to its weight in dry material the 

 yield for three crops in twenty months was equivalent to 8'72 

 tons per acre of dry material suitable for baling and ship- 

 ment. The growth of the plant on the heavy clay land of the 

 Botanic Gardens is poor as compared with the growth 

 attained on pegassy land on the banks of the Berbice and 

 ISarima rivers, where the stems frequently attain a height of 

 more than 5 feet. 



