45 



Plants attacked and Nature of Injury. The attacks of 



the Codling Moth are not confined to> the apple. Pears at times 

 suffer rather severely and the fruits of the quince, walnut, and 

 of various wild species of Pyrus may also be damaged, though 

 as regards these plants the pest is of little importance. 



In the case of the apple. Codling Moth injury may usually 

 be distinguished from that due to Apple Sawfly by the fact 

 that the larva has entered through the eye and has confined 

 itself mainly to the neighbourhood of the core, finally passing 

 out by a burrow to the side. The Sawfly larva, on the other 

 hand, usually both enters and leaves the apples by holes at 

 the side (as opposed to the eye), while instead of attacking 

 mainly, the core region, it eats out a large irregular cavity in 

 the flesh. In the case of Sawfly attack the decay produced 

 is more rapid and the apple seldom attains any size, usually 

 falling in June or July. 



Distribution and Economic Importance. The Codling 



Moth is an insect which has been able to adapt itself to prac- 

 tically every climate in which its chief host plant, the apple, 

 can be grown, and since it is easily carried in infected fruit, it 

 has now spread throughout the apple-growing regions of the 

 world. It appears to have been known to the ancient Komans, 

 and has certainly been long resident in Europe. 



In Great Britain the insect is abundant in England and 

 Wales, and occurs in Scotland and Ireland. Descriptions of 

 its life history were made in the 18th century, and it is 

 probably an old inhabitant of these islands, though its numbers 

 have perhaps been reinforced by the introduction of larvae in 

 infested consignments of apples from abroad. 



In Europe that is to say, in countries in which it has long 

 been resident it is always a troublesome pest, but its attacks 

 seldom attain the proportions which have marked its spread 

 through America, and Australia. 



In the latter country, the moth has been made the subject 

 of special legislation with apparently good results. It is 

 impossible to give any estimate of damage done in Britain by 

 the. Codling Moth, since confusion so frequently occurs between 

 the" Moth and the Sawfly. Further, the Codling Moth is most 

 numerous in old orchards and gardens attached to houses, 

 where little attention is paid to its ravages. In large com- 

 mercial orchards it does not seem to be such a serious pest 

 as is sometimes supposed, and this is explained by the facts, 

 (1) that trees in modern orchards are kept very clean, (2) that 

 spraying is carried out if necessary, (3) that there is usually 

 qrily one brood in the year. In America, where the annual loss 

 from the Codling Moth has been estimated at no less than 

 4.000,000, it is the occurrence of more than one brood in the 

 season which makes it such a dangerous enemy. 



There are several insect parasites of the C.odling Moth, and 

 birds also devour great numbers of the hibernating larvae, '.but 



