and Magazine of the Ceylon Agricultural Society.— Nov., 1910. 



m 



RUBBER IN SOUTH INDIA. 



U. P. A. S.I. Scientific Officer's Second 

 Tour in Cochin. 

 On 6th September I reached Trichur from the 

 Nilgiri-Wynaad and began a tour for the second 

 time in Cochin. The last time I visited this 

 district was in February last, but on this occa- 

 sion I traversed a different route, anil was able 

 to see several estates and localities which I did 

 not visit during my first tour. 



"Pink Disease" Prevention Experiments. 



The most interesting matter in this district is 

 the progress of the experiments which are being 

 conducted at r*alapilly and Vollanikana estates 

 in the prevention of Pink Disease (Corticium 

 Javanicum) on Para Rubber, a disease which 

 has done a considerable amount of damage. It 

 will be remembered that these experiments aim 

 at prevention rather than cure, and the trees 

 were painted in the dry season with Bordeaux 

 mixture so that the spores of the fungus, which 

 are wind-carried at that time and find a lodge- 

 ment on the trees, especially in the forks, 

 should germinate with the beginning of the 

 monsoon rains in a medium of Bordeaux mix- 

 ture which will kill them before the fungal 

 hyphae can gain an entry into the bark. The ex- 

 periments have yet a couple of months to run 

 before completion, so that it is perhaps too 

 soon to say very much about the results, but up 

 to date the treatment has resulted in complete 

 success, and the cases of attack have been re- 

 duced to a few individual instances, and these 

 are due probably to the careless application of 

 Bordeaux. Thus in one instance out of 60,000 

 treated trees there have so far been only three 

 cases of Pink Disease where formerly there 

 would have been hundreds. On estates -where 

 Bordeaux mixture has not been used, and 

 which therefore act as a check, the disease 

 has been as bad as usual, and attacked trees 

 may be put down roughly at something like 

 lper cent. Unless the unexpected happens dur- 

 ing the next two months wo have every reason to 

 congratulate ourselves that we have discovered 

 how to completely control Pink Disease. As soon 

 as the experiments are quite finished the whole 

 subject will be written up in detail in the Plan- 

 ters' Chronicle. I may, however, f.ay here that 

 the cost of the method will work out at about 

 half a pie per tree. Where Pink Disease is still 

 prevalent, measures are being generally taken to 

 deal with it as soon as it is noticed, aud most 

 estates have a ' pest gang ' going round and cut- 

 ting it out. Attempts at curing it by cutting 

 out the area affected, washing the wound with 

 Bordeaux mixture and tarring it, have generally 

 failed, and. as far as I am able to ascertain, some 

 70 per cent of such treated areas developed the 

 disease again in the following year. I still be- 

 lieve that, if carefully done and supervised, this 

 method is a correct one, but under estate condi- 

 tions it has not proved successful. Consequently 

 the affected branch should be cut off at least 18 

 inches below the point of attack. This is best 

 done with a mallet and a chisel, a neater and 

 smoother cut being made with this than with a 

 saw. In the case of an attack on the main stem, 



unless 3 feet of tappable trunk can be left, it is 

 better to cut the tree down close to the ground 

 and get a sucker from low down to replace it. 



A word of warning, given before, 



about' cutting branches 

 needs repeating. When a side branch is 

 removed it should be cut off parallel to that 

 from which it grows aud as close to it as possible 

 even if this necessitates a larger wound, and 

 not perpendicular to the branch cut off, leaving 

 a stub Bark will not grow over a stub, which 

 dies back gradually and at last falls out, leaving 

 a hole in which water collects, making an ideal 

 place for a fungus to grow. If a wound is made 

 close to the stem aud parallel with it, however 

 large it is, the bark will in time close smoothly 

 over it ; no protection agaitist fungoid enemies 

 is so good as nature's own covering, the bark. 



In connection with this work a disinfectant, 

 such as permanganate of potash of the usual 

 strength, for the k jives and chisels should be 

 used. As soon as a case has been dealt with these 

 should be washed in the disinfectant, and the 

 coolies should be made to wash their hands 

 before going on to the next tree. A cooly will 

 go to a healthy tree and rub his hands, covered 

 with spores, over it; and many instances are 

 known where healthy trees havu been infected 

 in this way. 



ON MOST RUBBER ESTATES PERMANGANATH 



is being used with good results, and a should 

 adopt it. 



The diseased portions cut off should be col- 

 lected and burned as near the spot as possible. 

 It is not advisable to carry them about the es- 

 tate any more than can be avoided. In some 

 places diseased branches after being cut off are 

 thrown into the nearest river, but this is a 

 practice which I cannot commend, and one 

 to which our Pest Act— when we get it— will 

 quickly put a stop. It is difficult to burn the 

 material in wet weather, but with the help 

 of a little kerosene it gets a scorching and 

 smoking sufficient to kill the spores, even if it is 

 not all consumed, and I saw very good fires 

 being made even while it was raining hard. 



The Weeding Problem. 



It is perhaps unnecessary for me to say any 

 more about the weeding problem than I have 

 already done in my report on my second tour in 

 Wynaad, (P.O., Vol. V, p. 487) but any one who 

 has seen Palapilly estate, even the most obsti- 

 nate of clean weeders, cannot help but be im- 

 pressed with the fact that to keep the soil, after 

 its first clearing and weeding, covered with a 

 legume for a year and then with a dense cover 

 pi Dadaps is the right way to grow Rubber. 

 It is at any rate impossible to cavil at the re- 

 sults obtained by that method on this estate. 

 It may be worth while to note here that Teph- 

 rosia purpurea is a very common weed in the 

 district and it will be seen growing in large 

 quantities on all the open land round Trichur 

 and its neighbourhood, 



Mr Kirk kindly gave me an opportunity, 

 which I very much appreciated, of seeing the 

 rubber machinery working at the 



