January, 1910.J 



37 



Plant Sanitation. 



saying that such a procedure for deal- 

 ing with the pest is out of the question." 



Mr. Antram finds, by experiment that, 

 failing young leaves, the adult insects 

 are able to subsist upon fully matured 

 leaves. The punctures are clearly visi- 

 ble, but the leaves "do uot curl up 

 or become deformed as in the case of 

 young leaves." Insects kept entirely 

 without food invariably died within 

 two days. 



The second part of the first circular 

 deals with remedial measures, and 

 it is this section that will be of the 

 greater interest to tea planters in 

 Ceylon, As I have the author's per- 

 mission to make full use of his circulars, 

 I quote the following passages without 

 further comment. 



"There are two methods of dealing 

 with the pest, and that at the most 

 convenient time of the year, namely, 

 at the pruning season." 



" It has been shown that those insects 

 reaching maturity towards the end of 

 the cold weather survive the rest of 

 the cold weather, during which time 

 they are laying eggs. It is these in- 

 sects that are responsible for the count- 

 less number of insects which turn up 

 later in the year and do so much 

 damage." 



''For the destruction of these the 

 method is simple enough, and is brought 

 about by the burning of all pruniugs 

 while they are still green, the best 

 method being to burn the primings the 

 same day they are cut from the bushes. 

 The area pruned in one day should be 

 cleared that same day, and no primings 

 allowed to remain on the ground or in the 

 pruned bushes. If the pruned area can 

 then be hoed overand thoroughly cleaned 

 up immediately after pruning, this will 

 do away with fallen leaves and bangy 

 shoots that have been cleared out of the 

 bushes. The leaves, etc., properly 

 bUried, cannot produce insects, as the 

 latter are so fragile when just emerged 

 from the egg that they would find it 

 quite impossible to work their way 

 through the soil to the surface." 



In the case of very light primings, if 

 these can be hoed into the ground and 

 completely covered by the soil, removal 

 of the prunings for burning need not be 

 resorted to. Conditions now are such 

 that a cold weather hoe immediately 

 after the pruning is clearly indicated, 

 specially if spraying is to be carried out 

 after pruning. When the area is clean 

 and the collars of the bushes are free 

 of weeds, the insecticide can be applied 

 with greater economy." 



" During these investigations, experi- 

 ments have proved that insects will 

 hatch from eggs in prunings lying on 

 the ground up to fourteen days, or so 

 long as the tops of the prunings are not 

 absolutely hard and dried up. With 

 heavy priming the shoots remain fresh a 

 long time, especially when lying; in damp 

 nullahs or on the shady side of bushes 

 and edges of the jungle." 



" Burning the prunings the same day 

 they are cut from the bushes will, at 

 that time, destroy all eggs laid by 

 insects during the previous fifteen 

 days." 



" In the removal of prunings and the 

 cleaning up of the area by hoeing as 

 above suggested, together with careful 

 thinning out in pruning of all useless 

 twigs and ' bangy' shoots, it is only the 

 eggs and some immature insects that 

 have been dealt with. The next process 

 is the treatment of the pruned bush by 

 spraying, the object being to destroy 

 all living ' mosquitoes,' whether im- 

 mature or adult, that have been left 

 behind on the bushes after pruning, and 

 by the destruction of which further 

 deposition of eggs will be prevented. 

 Spraying must be carried out as soon as 

 possible after pruning, as, if delayed, 

 eggs will be deposited in the pruned 

 bushes. We are now able to recommend 

 an insecticide that is cheap and easy 

 to use ; three or four boys kept for 

 spraying affected bushes all the year 

 round will do a hundied times more 

 than a large number of collectors." 



"It was found, by careful experiment, 

 that Kerosene Emulsion kills only those 

 insects it comes in contact with at the 

 time of spraying, and the presence of 

 the material on the bushes does not 

 prevent the insects from feeding on the 

 sprayed foliage, neither has it the effect 

 of stopping insects from laying their 

 eggs in the bushes. More than this, the 

 emulsion in no way prevents emergence 

 of insects from eggs that have received 

 the spray, and as conclusive proof, it 

 was found that a number of eggs con- 

 tained in shoots that had been dipped 

 in pure kerosene oil produced young 

 insects that lived to reach maturity." 



"After long experiment, I have been 

 successful in finding a solution which is 

 equally as deadly in its action on the 

 insect as Kerosene Emulsion, and at 

 the same time can be applied at twice the 

 rate per acre at one quarcer the cost of 

 the latter. In January last 'Primrose' 

 soap 1 lb. and water 20 gallons was 

 recommended as the composition ^of 

 Soap Solution for Mosquito Blight, but 

 since that date the 'Imperial' brand 

 has been discovered to be in every way 



