LecaniincB. 201 



Unfortunately, at the time of the invasion, our coffee had been weakened 

 by long-continued attacks of ' leaf disease ' {Hemileia vastairix). Moreover, the 

 prevailing system of cultivation resulted in the loss of the surface soil, so 

 essential to the health of the coffee plant, in all but the most favoured situa- 

 tions. The further tax upon its strength induced by these myriads of sap- 

 imbibing insects proved too great for the plant, with the result that thousands 

 of acres of coffee-land were abandoned or replaced by tea. Some idea of the 

 collapse of the coffee industry may be obtained by comparing the annual 

 export of coffee during the period of attack. In 1881, 452,000 cwts. were 

 shipped from Ceylon. In 1891 this figure had fallen to 88,780 cwts. While, 

 during the past year (1902), the total scarcely exceeded 10,000 cwts. 



It must not be supposed that no efforts were made to check the invasion. 

 When the pest first appeared on any estate, individual plants and small patches 

 of affected trees were frequently cut out and burnt. But nothing stayed the 

 progress of the invader. The fact is, the insect being an inconspicuous one, 

 by reason of its colour and small size, it was not noticed until it had established 

 itself in sufficient force to defy all efforts at extermination. All the old remedies 

 that had obtained a (usually spurious) reputation as effective against the old 

 brown bug were tried without success. Affected trees were swathed in freshly 

 freshly cut ' Mana grass ' {Andropogon nardus). They were dusted with dry 

 lime and wood ashes. But all to no effect. Following out some previous 

 experiments with coal-tar applied to the roots, the writer applied dilute phenol 

 and carbolic powder to the soil below the trees. The former application was at 

 first thought to have proved successful (see Report on Green Scale Bug, 1886, 

 footnote to page 3). But subsequent and more extensive experiments, carried 

 out in the same way, negatived the earlier result. The original experiment 

 was on too small a scale to provide a proper test. Lime and water, applied as 

 a thin whitewash, by hand, killed every bug with which it came in contact ; 

 but it was found impossible to apply it in a sufficiently thorough manner, and 

 the process was too costly in labour, when large acreages were to be 

 treated. The same remark applies to all other liquid applications. They 

 were both costly and inefficient. Many fancied cures owed their repu- 

 tation to the death of the insects from natural causes. For, quite from the 

 commencement, the pest had its periods of increase and decrease. These 

 periods vary in different parts of thes island according to the prevailing 

 weather. The bug flourishes best during the time of fine weather interspersed 

 with light showers. It objects to extremes, and usually decreases both in the 

 very wet weather and during times of excessive drought. In districts subject 

 to a heavy south-west monsoon, the pest is at its height from the middle 

 of March to the middle of June, when it is checked by the continuous rains. 

 There is a recrudescence from September to January, when it again decreases 

 during the dryest months. On the other side of Newera Eliya, I am 

 informed that the bug usually appears towards the end of April, and reaches 

 a climax in October or November. If there is any very wet weather in the 

 mean time, it temporarily declines, but flourishes in times of light rain with 

 intermediate sunshine, and disappears almost completely from December 

 to April. 



The periods of decrease are marked by the death of fully 90 per cent, of the 



