258 



EXPERIMENTAL FARMS. 



destroying the pest. If windfalls are left lying in an orchard, the maggots will leave them 

 and enter the ground; but they always remain near the surface, so that deep spading or 

 ploughing would bury most of them so deeply that the flies would be unable to emerge. A 

 most useful practice also is the penning up of poultry beneath infested trees ; these will 

 scratch out and devour large numbers of the insects." 



It is hardly likely that the fllies were attracted by the odour of the manure applied 

 by Dr. Young to some of his trees or by the pig-pen beneath others, but the observation 

 is well worthy of being remembered in case the Apple Maggot spreads and becomes more 

 destructive in Canada. A characteristic of the occurrence of this insect is its slowness 

 in spreading from one locality to another, from orchard to orchard, or even from variety 

 to variety and from tree to tree in an orchard. It is said to be largely confined to 

 sheltered locations and sandy soils. 



THE APPLE FRUIT-MINER 



Fiff. 16. — Apples injured by Apple Fruit-miner. 

 Attack. — Small caterpiilai's tunnelling in all directions through the flesh of apples, 

 discolouring them and rendering the fruit unfit for use ; when full-grown, they are a 

 Httle over a quarter of an inch in length, dirty white in colour, tinged with pink just 

 before spinning their cocoons. Head and a small shield at the end of the body, dark 

 brown, somewhat resembling the caterpillar of the Codling Moth, but only about half its 

 size when full-grown, and with the body much more tapering to each end. When ready 

 to spin up, these caterpillars leave the fruit and make cocoons which in nature are pro- 

 bably placed in crevices of the bark in the same way as those of the Codling Moth. 



Fig. 17. — Apple injured by Apple Fruit-miner (inside). 

 Nothing is known of the egg-laying habits of the moth from which the cater- 

 pillars spring, but, from the appearance of the infested fruit at the entrance of the tunnels, 

 it would appear possible that the young caterpillar may live at first for a short time on 

 the foliage or beneath a leaf attached by it to the fruit. A point of entry is frequently 

 marked by several very small tunnels opening over the surface of a comparatively large 

 area one-eighth of an inch to one-quarter of an inch in diameter, as if the insect had fed 



