b8 The Tea insects of India. 



until appreciable injury has been done; for preparations which mi^ht 

 profitably be employed to kill off the pest on the few bushes where it 

 first appears, and thus prevent its spreading wholesale throughout the 

 garden, are liable to prove too troublesome and expensive for application 

 at a later date when large areas have become affected. 



Methods capable of more or less completely destroying almost every 

 form of insect blight have now been invented in America and Europe. 

 The relative merits also of almost every substance which possesses in- 

 secticide properties have been so fully thrashed out by the United States 

 entomologists, that little is likely to be gained by attempts to invent 

 new insecticides in India. Wliat is rather required is to adapt already 

 existing systems to the special requirements of the tea industry and to 

 ascertain by experiment how to attain the most satisfactory results with 

 the least possible expenditure. 



The period immediately after pruning, when the bushes are small 

 and thin, is no doubt a favourable one, under certain circumstances, for 

 treating large areas for the destruction of such pests as red spider and 

 scale insects which remain all the year round upon the plants ; but the 

 shock likely to be caused to the bush by the application of poisonous 

 substances must also be taken into consideration, and the object should 

 be to select a moment for operation when the insect is most 0[5en to 

 attack and the plant least liable to be affected. 



With a few unimportant exceptions, the species which attack tlie tea 

 plant in India are confined to Southern Asia; they are sufficiently closely 

 related, however, to corresponding American and European forms to be 

 likely to be to a very large extent amenable to the same insecticides. For 

 this branch of the subject, therefore, the masterly publications of the 

 United States Entomological Department are of the greatest use, 

 though great care must be taken only to institute comparisons between 

 species which have essential features in common. 



The sulphur treatment for red spider, which has been fully described 

 on pages 52 to 56 of this report, may be said to have already passed into 

 the stage of practical utility in India. Sulphur has long been employed 

 both in Europe and in America for the destruction of mites of all kinds, 

 of which the red spider of the tea plant is one. Sulphur is therefore 

 likely to be useful in India, not only against red spider but also against 

 such species as TypModromus carinat7is and Acarus transltccens reserved 

 to on page 57 of this report. Whether, however, the system, hitherto 

 adopted in Indian tea gardens, of sprinkling the sulphur in a dry powder 

 over the bushes, will eventually prove to be the cheapest and most 

 effectual method of application, is open to considerable . doubt. Both 

 in England and in America this system seems to have been generally 

 abandoned in favour of mixing the sulphur with soap which is then 



