28 PKOCEEDINGS OF THE THIRD ENTOMOLOGICAL MEETING 



bush above ground and that they do not as a rule go below the collar of 

 the bush. In that part of the world there is a system of pruning by 

 which the plants are cut at 12 inches and plucked somewhere above 

 that. This results in the formation of a high central stump in which 

 the termites can find lodgment. By working there they can cut off the 

 supply of sap to the upper portions of the bush, and can only be eradi- 

 cated by cutting away the whole bush. We advocated collar-pruning, 

 i.e., pruning the bushes to the ground. By this means a bush is formed 

 which consists of a circle of branches arising directly from the collar of 

 the bush. There is no central stump to afford a lodging to the Termites, 

 and as they do not work below the collar they cannot affect the several 

 branches until after some years, when they are becoming moribund. 

 When this occurs a number of the branches can be cut back in successive 

 years — an operation which must be carried out in any case in order to 

 get leaf, and the bushes thus consist always of strongly-growing branches 

 which are not attacked by termites. This method of prevention has 

 proved entirely successful. There is another case in which methods of 

 cultural control are successful and that is in dealing with Melolonthid 

 and other beetles. These beetles invariably attack new tea wherever 

 jungle land is cleared and freshly planted. When the jungle is cleared, 

 and the tea plantsd, the grub is still there, and the beetles attack the 

 bushes, but in four years' time practically no damage can be seen. 

 Continued hoeing and forking, given year after year, five or six 

 times during the year, gradually kills out the insects, until they are 

 present in such stoall numbers as to be incapable of doing any 

 appreciable damage. We have another instance, which I gave you last 

 year, in which such methods have been successful in the case of the 

 looper caterpillar. 



Another question which must be considered is that of the relation 

 between the insect and the plant plia; the relation of the plant to its 

 environment, and this is a line of inquiry which I think must always 

 be followed. I can give you an instance of this in the case of red spider. 

 There are certain places in which tea is always attacked by red spider, 

 others in which it is never attacked. Of two gardens adjoining one 

 another red spider may be serious in the one, and none may occur in 

 the other, although, so far as the insect itself is concerned, the condi- 

 tions are exactly similar. Vv'^hat causes the difference ? Probably it is 

 in the nature of the bushes. If that is so, then if we can by any means 

 alter the condition of the bushes which are attacked and bring it into 

 line with the condition of the others which are not being attacked, we 

 may reasonably hope for success in control. We find that in the case 

 •of red spider drainage has considerable effect. We know that bad 



