Nov., 1910.] ANNUAL REPORTS. 43 



A series of experiments were conducted to determine whether fruit of a given 

 variety infested with the maggot would deteriorate any more quickly in cold 

 storage than other fruit of the same variety not so infested. It was found 

 that as a rule the deterioration is more rapid in the case of infested fruit. 



Throughout July and August studies were made to determine the extent 

 of the egg-laying season. It was found that the first eggs are laid soon after 

 the flies begin to emerge, about July 2 to 5, and that egg laying continues 

 through July and August, and probably into September. This is true regard- 

 less of variety, except, of course, that eggs are not laid in early apples after 

 they have ripened and dropped from the tree. 



In determining these points trees of several varieties were selected in locali- 

 ties where flies had been observed the previous season. Clusters of fruit were 

 encTosed in cheesecloth bags prior to the beginning of the egg-laying season. 

 Certain clusters were then exposed to infestation each week, the bags being 

 replaced at the end of the week. An examination of the ripe fruit at harvest 

 time disclosed the total period of egg laying, and to some extent indicated the 

 period of greatest activity. 



Experiments were made to determine whether maggots may mature in 

 winter fruit, such as the Baldwin. It was found that where such fruit becomes 

 infested, the early drops, that is those falling in August, may easily become 

 sufficiently mellow to permit the maggots to mature. On the other hand, 

 badly infested Baldwins gathered early in October failed to mature a single 

 maggot. The same was found to be true of Russets. It is the early drops, 

 therefore, that should be disposed of, in the case of winter varieties. 



The surest means of control for the Apple Maggot has always been the 

 practice of keeping all drops picked up. There have been no records, however, 

 which would indicate how often the dropped fruit should be gathered. 



Experiments were arranged, therefore, to determine this point for ten 

 typical varieties of apples. Trees were selected that bore abundant crops 

 of infested fruit. All the drops under each tree were gathered once every 

 twenty-four hours. These drops were then maintained under observation, 

 and records kept showing when the maggots began issuing from them, when 

 they issued in greatest numbers, and how long they continued to emerge. 



It was found that in t"he case of 6uch varieties as the August Sweet or the 

 Early Harvest some maggots began to emerge within thirty-six hours, though 

 they did not come out in large numbers until three or four days had elapsed 

 since the apple fell from the tree. With varieties such as the Gravenstein a 

 week elapsed before the maggots began issuing in any considerable numbers. 

 In the case of winter fruit, such as the Westfield, practically no maggots 

 emerged until after the apples had been off the tree from two to four weeks. 



In practice, therefore, a grower may readily eliminate the pest from a given 

 block of trees if he will arrange to keep all drops picked up at appropriate 

 intervals. In the case of such early maturing fruit as the August Sweet it 

 may be advisable to make use of livestock, such as swine, to care for the drops 

 as they fall. Usually this can be done by erecting a temporary fence around 

 the tree or trees that are infested, and enclosing one or more pigs within 

 In the case of fall fruit it will suffice if all drops are cleaned up twice a week. 

 With winter fruit once in two weeks will "suffice. 



