1920.] 



The Injurious Apple Capsid. 



381 



the developing leaves. Further, a very few bugs are capable 

 of doing great injury, and therefore the majority of the insects 

 must be killed if real benefit is to be gained. A fairly coarse 

 nozzle should be used so as to get a driving spray, which should 

 be directed first downwards into the trusses and leaves of 

 a branch passing from the tip to the trunk, and then back again 

 to the tip after turning the nozzle upwards, so as to catch bugs 

 sheltering underneath the leaves. 



The best time to spray varies with the season, but it is gener- 

 ally during the w^eek or ten days immediately preceding the 

 bursting of the blossom. A watch should be kept for the first 

 signs of spotting of the leaves — then, after an interval of ten 

 days to allow the majority of the bugs to hatch, the spray should 

 be applied. Much good can be done by one spraying, but in 

 a badly affected orchard, especially if a good crop is anticipated, 

 it is better to sprav again immediately after the petals have 

 fallen. 



The best insecticide to use is nicotine, which should always 

 be combined with soap or paraffin emulsion to assist it to run 

 freely in the trusses and between the young leaves. The 

 following formula has proved satisfactory : — 



Nicotine (98-99 per cent.) . . . . . . 3 oz. 



Soft soap . . . . . . . . . . 4 lb. 



Water . . . . . . . . . . . . 40 gal. 



This wash is, of course, expensive, but it is waste of labour 

 and time to spray against Capsids with a wash which is not 

 highly efficient. Further, nicotine and soap will kill aphides, 

 apple suckers, and a good proportion of any winter moth 

 caterpillars which may be present, and it is therefore a good 

 " general purpose " spray. 



References. — (i) Fryer, J. C. F. — Preliminary' Notes on Damage to 

 Apples by Capsid Bugs. Annals of Applied Biology, Vol. I., No. 2, 

 July, 1914. 



(2) Petherbridge & Husain. — A Study of the Capsid Bug found on 

 Apple Trees. Annals of Applied Biology, Vol. IV., No. 21, March, 191 8. 



2 D 



