92 THE EEPOKT OF THE _ Nw. 3 'J 



which had heen badly infested the previous year. The results here, too, were very 

 satisfactory, only a very few apples being punctured, and nearly all of these on 

 trees situated at some distance from the main orchard and near two trees that 

 had received only one partial spraying. 



In the fall of 1917 we found the worst infested apple orchard that we had 

 yet seen. It consisted of nearly three hundred trees, including Snow, Wealthy. 

 Tolman, Belleflower, Ben Davis and half a dozen other varieties. There had been 

 a good crop, which if clean should have been worth $1,000 at least, but every apple 

 that we could find on any variety was punctured by the insect and nearly all of 

 them so badly punctured as to be conspicuously deformed. We therefore decided 

 to make this orchard our final test. In 1918 it was given the regular sprayings 

 for Apple Scab and Codling Moth, and then two extra fairly heavy applications 

 for the Apple Maggot, the first of these being on the 12th and 13th of July and 

 the next the first week in August. Orchards close by were sprayed to act as buffer 

 orchards. 



Eesults : The whole orchard was l^eautifully free from Scab and Codling 

 ]\Ioth, and the effect upon the Apple Maggot was a clear demonstration of the 

 power of poison sprays to control this pest ; for instead of 100 per cent, of punctured 

 fruit there was less than 5 per cent. Apple buyers, fruit growers and everybody 

 who visited the orchard this year and hael seen it last year were convinced that 

 our method was as nearly perfect as anyone could hope for. There is no doubt at 

 all that without the spraying the crop would have been ruined by the Apple Maggot, 

 for one of the writers visited the orchard every few days from the time the flies 

 began to emerge up to the end of July, and saw that they were very abundant. 

 It was no trouble to capture twenty or more on a single tree in an hour even without 

 a net. Moreover, a neighbouring orchard used as a check but so situated as not 

 to endanger our test orchard was also visited frequently to see how many flies were 

 present. (This orchard had not been badly infested the previous year and the fruit 

 on it had been sold.) Eight or ten flies was the largest number seen on any one day ; 

 yet at the end of the season the Snows, Wealthy, Ben Davis and Phoenix in this 

 orchard had 75 per cent, of the fruit infested, in fact so bad was the fruit that the 

 chief apple buyer of the district, who had bought the fruit on the test orchard, 

 absolutely refused to buy the crop on the check, declaring that it was worthless. 

 It may be of value to note that though so many flies were seen in the sprayed 

 orchard yet at no time were they observed copulating or ovipositing, whereas in 

 the check orchard oviposition was observed on several occasions and egg punctures 

 could be readily found before the end of July. Xo egg punctures w^ere visible in 

 the sprayed orchard at this date or at the time of the second spraying, all having 

 evidently been made much later. 



CONCLUSION'S. 



The results of our field tests conducted in various parts of Ontario and spread 

 over five consecutive years and corroborated by laboratory tests justify us, we believe, 

 in stating confidently that the Apple Maggot can be successfully controlled in apple 

 orchards by spraying. 



The first application should be given Just before or as the adults begin to 

 emerge, which in the south-western part of the Province is about the last week in 

 June, and in the parts with a somewhat colder climate such as Guelph, Stratford 

 and the district all along Lake Ontario, about the first week of July, and in the 



