July, 1914.] THE APPLE MAGGOT. 55 



although here again the direction of winds and similar matters 

 may play an important part. 



Adults emerging beneath fruiting trees of the less acceptal)le 

 varieties, such as the subacid fruits, seem to follow the same 

 general habits as described in the last paragraph, concentrating 

 their attention largely on any preferred variety near by, or dis- 

 persing in general fashion in the lack of such variety. 



In localities where much early and neglected fruit grows, and 

 in a year when there is a light crop of fruit following a season 

 of abundant opportunity for increase of the maggot, especially 

 if early fruit has failed, the combined results of forced dispersion 

 of adults from non-fruiting acceptable varieties may approxi- 

 mate a general dispersion. 



Basis of Conclusions. The above conclusions are drawn 

 from observations and field notes by the writer and his assistants 

 during the last four years, and from the experiences of growers. 

 Space will not permit reproducing these notes in this bulletin in 

 the detail that would be necessary to render them of any value. 



In general it may be stated that, repeatedly, instances were 

 found where trees of like susceptibility, located often within a 

 short distance of one another, showed marked difference in the 

 extent of infestation by the maggot. Often such trees were of 

 the same variety, and frequently the difference in infestation per- 

 sisted in similar manner from year to year. Usually, the trees 

 remaining free of the maggot were so located that drops were 

 cleaned up by livestock, or the fruit used up clean by the owner, 

 while the infested trees received the reverse treatment. In 

 some cases the practice of an orchardist in the matter of care 

 of his fruit, including disposal of drops and spraying, appeared 

 to give him practical immunity from the maggot, while his 

 neighbors, perhaps located not more than a quarter of a uiile 

 away and with similar varieties, following careless methods, 

 suffered severely from the maggot. 



The deduction naturally made from such observations was that 

 the adults of this species tend distinctly toward localization. 



On the other hand, certain localities were found where some- 

 thing like general dispersion of the adults seems to come about 

 practically every season. These localities appear to be charac- 

 terized by an excessive amount of early or neglected fruit, or both. 



