Insects Injurious to the Apple. 



143 



any patches with methylated spirit, and yet they send out infected 

 stock. The reason is obvious : they either do not know or discard 

 the presence of fic/iizoneura lanigera on the roots. The complete life- 

 history of this apple enemy is well known, but this knowledge is not 

 sufficiently widespread to bear any fruitful results. 



So numerous have been inquiries concerning this pest during the 

 last few years, that it is thought that a somewhat fuller account 

 than usual of its life-history should be given here, together with an 

 account of some recent experiments carried out in connection with its 

 prevention and treatment. 



The area over which it occurs may be but briefly mentioned ; 



[A. V. D. Rintoul. 



FIG. 117. WOOLLY APHIS ON THE SUCKERS AND SHOOTS OF AN 

 OLD APPLE TREE. 



enough to say that wherever apples are grown, the blight also is 

 found. 



At one time it seemed to be mainly prevalent in the old west- 

 country orchards in Britain, especially amongst the somewhat ill-kept 

 cider apples. Now we find it just as bad in young plantations of the 

 best varieties all over the country. 



It is perhaps most abundant in Worcestershire, and in the Devon 

 orchards, but in all other centres it is an important and increasing 

 enemy. It has been reported to me, or observed in all parts of Kent. 



