Plant Sanitation. 



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than on any previous occasion. I believe that most of u.s are agreed that the 

 pest is always worse when we have abnormally dry weather. Both years that 

 1 remember our having it badly were dry years ; and this year we have had 

 a more obstinate drought since the middle of November than I ever remember 

 before. If we have an old-fashioned monsoon, followed by a wet N.-E., I dare 

 say many of us will think this time next year that we were unduly pessimistic ; 

 on the other hand if the S.-W. and N.E. are partial failures this year, 

 and we do nothing, then Heaven help us, as I fear the present attack will 

 be nothing to what we shall have next year. At present I believe we know 

 very little about this pest. From the time the female deposits its eggs until 

 the moth is hatched is, I believe, about six weeks. From what I have noticed 

 myself, and from what others have told me, it is generally worse on wind-blown 

 ridges, and on poor soil where little or no cultivation has been done. It is, I 

 think, natural that it should be worse on the ridges, as the tortrix does not 

 like damp, and the sooner the leaves dry the better the tortrix thrives. Mr. 

 Pole, who is undoubtedly the leading entomologist in Maskeliya, informs me 

 that it is never bad under grevilleas. If we had not cut up our grevilleas he 

 says the pest would not have been nearly so bad, as the tortrix infinitely prefers 

 grevilleas to tea. To a certain extent I agree with him, as I find the pest on 

 the whole much worse where there are no grevilleas than where they are growing 

 thick. On the other hand I have found it decidedly bad on places where the 

 grevilleas are growing thick, though it is certainly not nearly as bad as where 

 there is no shade. On the other hand, another resident reports that it is not 

 bad except on the fields where the grevilleas were thick ! So you will notice 

 how divergent our views are. So far several remedies have been tried, but with 

 no great success on the whole. The one that has, perhaps, been most tried is 

 that the pluckers should bring in all egg masses they see, and they are paid a 

 small sum per hundred. This on the whole has, I fear, been a failure. It is 

 quite impossible for the pluckers to take off evexw egg mass, and the egg masses 

 left probably hatch out stronger caterpillars as they have more to eat. Another 

 plan has been to hang up grevillea branches, and to send coolies round to 

 collect and kill the moths every morning. 



This again has been more or less of a failure, as most of the females caught 

 have already deposited their eggs. Another proposal is to at once burn or bury 

 all primings. I have doubts as to whether this would do much good, as nowadays 

 almost every leaf is taken off, and there would be nothing for the caterpillars to 

 feed on. It would, however, be interesting to know if the egg mass could live in 

 the dead leaves of the prunings, and hatch out when the young shoots have started. 

 The only other remedy I can think of is that we should send separate gangs round, 

 whenever either the superintendents or kanganies notice any signs of egg masses, 

 and have them all carefully taken off, and at once burnt. The plucking kanganies 

 would soon notice if there were any masses, and would at once inform the superin- 

 tendent. I understand that Mr. Neale, on Chapelton, tried this experiment with 

 great success. I believe, at the present moment, it is not much use doing this, 

 as most estates will want their labour for plucking. The probability is that the 

 monsoon will destroy most of the tortrix, and I have never known the pest bad 

 in June, July, and August ; but if everyone from August on to the end of the year 

 was to tackle the pest seriously, I think a great deal of good would be done. 

 However, whatever we finally decide is for the best, I earnestly appeal to 

 every planter in Maskeliya to co-operate, and to do everything in his power 

 to cope with this pest. If we can only all combine, 1 believe that half 

 the battle is won. Whatever we decide on to-day I strongly urge 

 that every superintendent in the valley back up to the best of his 



