192 



The Supplement to the Tropical Agriculturist 



will fall off, or at any rate the first shower of 

 rain will wash the leaves quite clean. The mate- 

 rial I have found effective is a paste made with 

 flour, or some other form of starch, which has 

 been well boiled. A small quantity of this 

 mixed with the water serves to fix the poison to 

 the leaves sufficiently firm to withstand the rain. 

 The mere contact of the poison with the body of 

 the insect has no effect, it must reach the organs 

 of digestion and be absorbed before it becomes 

 operative. The object of spraying is therefore, 

 to deposit a film of poison on the leaves which 

 will subsequently be consumed by the leaf- 

 eating pest which it is wished to destroy. 

 Destructive Beetle. 

 Recently, considerable damage has been done 

 to some young rubber trees at Lauderdale 

 Estate, Matang, by the attacks of a green leaf- 

 eating weevil, which I identified as Astycus 

 chrysochlorus, Wied. In 1897 this same beetle 

 did a very large amount of damage to many 

 acres of Liberian coffee at Gapis Estate ; and at 

 the request of Sir W H Treacher I worked out 

 its life history. The report, which was dated 

 July 27, 1897, was published in Perak Museum 

 Notes, Vol. II., Part I., p. 61-8. From this I 

 will quote the summary, which will be sufficient 

 here : 



ITS HABITS. 



The egg is laid in a small hole in the surface 

 of the ground. On hatching, the grub burrows 

 into the soil and lives on the well-rotted roots 

 and other vegetable matter contair ed in it. Hav- 

 ing attained a size of about § of an inch in length, 

 it forms for itself a chamber in the earth, about 

 2 inches below the surface, in which it under- 

 goes its metamorphosis. The perfect insect bur- 

 rows its way out of the earth at night and flies, 

 probably the next day, in search of food. Hav- 

 ing found a tree on which it can live, it stays on 

 it while there is any leaf to eat, the females 

 leaving the food plant from time to time to de- 

 posit their eggs in the ground. 



ONLY SATISFACTORY KEMEDY. 



The results of digging showed that the grubs 

 were most frequent in the cleanest land. I dug 

 in grass and weeds in many parts of the estate, 

 but could not find one. The same results fol- 

 lowedd igging in scrubes and lalang land, and also 

 under the hedges. . . In the clear land, in 

 one place, as many as six grubs were found 

 within an area of less than one square yard, 

 but, on an average, there are not more than one 

 or two per square yard. Of course, the younger 

 ones being very small undoubtedly escape jbser- 

 vation when turning over the soil. At one per 



square yard we get 4,840 per acre, which is a 

 sufficiently large total to account for a very ex- 

 tensive destruction of foliage. Taking into 

 account the life history of the insect, there 

 appears to be only one period of its life when it 

 is possible to attempt to destroy it — and that is 

 when it has attained maturity. Then it might 

 be collected by hand picking or killed by pois- 

 oning its food supply with one of the arsenical 

 powders applied as previously mentioned. Mr. 

 E. Lauder Watson informs me that he has 

 nearly exterminated it by hand picking. The 

 same method was also reported by the late Sir 

 Groeme Elphinstone to be effective in ridding 

 the Liberian coffee on Gapis Estate of the same 

 pest, — Straits Times, Feb. 12. 



THE PALM DISEASE. 



ARECANUTS THE LATEST TO BE 

 ATTACKED. 



The latest information about the Bleeding 

 Disease is that in addition to it attacking 

 coconut and palmyra palms, it has made its 

 appearance among arecanut palms, so that there 

 is every warrant for believing that the disease 

 is general among palms. Unless checked 

 in time the mischief that it will create to the 

 palmyra industry of the North will be even more 

 disastrous than aujthing that can happen to 

 the coconut industry, for the palmyra palm 

 is the main stay of the thousands of people 

 in the North. There is the need also now for 

 looking out for the disease among the kitul 

 palms, where the interests of the Kandyans are 

 so greatly centred. 



Preventive Measures. 



Mr. Petch, in the company of Mr. Drieberg 

 and Messrs H. L. de Mel, L. W, A. De Soysa and 

 Mathias de Mel have been visiting Moratuwa 

 and inspecting some gardens where the disease 

 has appeared. Hitherto only curative measures 

 have been adopted, but on the recommendation 

 of Mr. Petch preventive measures are now being 

 taken in respect of the young trees. This con- 

 sists of spraying the trees with a solution of 

 sulphate of copper and slaked lime, the quanti- 

 ties necessary being equal parts of sulphate of 

 copper and slaked lime, say 6 lbs., and 25 gallons 

 of water. Thousands of leaflets in the verna- 

 cular have been issued by the Secretary of the 

 Agricultural Society containing advice as to how 

 to combat the disease. For the guidance of 

 others Mr. Petch is to give demonstrations in 

 various centres and a start, as already announced, 

 was made at Negombo on the 18th Feb. 



