The Canadian Horticulturi^ 



Vol. XXXVII 



DECEMBER, 1914 



No. 



12 



* 



Prof. L. 



CHERRY Fruit Flies, at least in the 

 Niagara district, which is our 

 chief cherry district, are by far 

 the worst cherry insects we have. They 

 do much more injury than the Plum 

 Curculio and Cherry Aphis together. 

 The injury is caused by the flies with 

 their sharp sting-like ovipositors laying 

 their eggs just under the skin. The 

 maggots that hatch from these work 

 their way to the pit, where they destroy 

 the pulp, causing the interior to be- 

 come unsightly and the cherry to be un- 

 fit to eat. In many cases there is little 

 or no sign of the presence of the maggot 

 until the ch^ry is opened. Often, how- 

 ever, the skin above the place where the 

 maggot is working turns brown and 

 sinks in and frequently there is a little 

 round hole or two in it made by the mag- 

 gots to ensure an abundant supply of 

 fresh air. There is usually only one 

 maggot in a cherry, but occasionally 

 two, three, or even four may be found. 



The maggots are ordinarily glossy 

 white in color, though some are cream or 

 even yellow. They are about one-quar- 

 ter of an inch long when full grown, 

 scarcely so thick as a knitting: needle, 

 tapering sharply towards one end and 



•An a<l<ir€se delivered at the recent convention 

 in Toronto of the Ontario Fruit Growers' Asso- 

 ciation. 



Cherry Fruit Flics 



Caesar, Provincial Entomologist, O.A.C, 



blunt at the other. They have no legs 

 and no head, but at the small end are 

 two little black hooks that they can pro- 

 trude and retract at will, and with which 

 they tear the pulp to free the juice. The 

 maggots devour only the juice. 



Another source of injury due to these 

 insects comes from the fact that infest- 

 ed cherries as they ripen are commonly 

 attacked by Brown I^^ot, and then spread 

 the disease to neighboring cherries. 

 Moreover, the sale of wormy cherries in- 

 jures the market for good cherries. 



SUSCEPTIBLE VARIETIES 



The cherries worst attacked are Mont- 

 morency and all sour cherries that ripen 

 as late or later than these, also all late 

 sweet varieties. Early varieties, like 

 Early Richmond, are almost immune, 

 probably because they are nearly ripe 

 before the flies are ready to lay eggs, 

 and because the flies prefer to lay eggs 

 in green cherries or those just begin- 

 ning to color. 



Not all the orchards in the Niagara 

 districts are attacked, but rnany are, and 

 a considerable percentage of these are 

 among the very best orchards in the 

 country. The amount of injury varies 

 from year to year greatly. Some infest- 

 ed orchards will have only about five per 

 cent, of the fruit wormy ; others equally 

 as well cared for will have ninety-five per 



Guelph 



cent. It is not an uncommon occurrence 

 to find beautiful Montmorency cherry 

 orchards so badly infested that the fruit 

 is not picked. Some growers, especially 

 in towns, have become so discouraged 

 that they have cut down part of their 

 orchards. It was clear, therefore, to me 

 that if I wanted to help cherry growers 

 I could not do so in any better way 

 than by trying to find a remedy for this 

 fjest. 



WHEN DISCOVERED 



The first discovery of Cherry Fruit 

 Flies in Ontario as the cause of wormy 

 cherries was made by me near St. Cath- 

 arines in 1910. Only one species, which 

 because of the white cross bands on its 

 abdomen I shall call the White-banded 

 Cherry Fruit Fly, was discovered on 

 that occasion. In 1912 I discovered in 

 the same locality, but in a different or- 

 chard, another species resembling close- 

 ly the former, but easily distinguished 

 by having the abdomen entirely black, 

 without any of the above-mentioned 

 white cross bands. This sjjecies I, 

 therefore, purpose to call the Black- 

 bodied Cherry Fruit Fly. Both species 

 of flies have undoubtedly been in the 

 province for many years, but no one 

 ever knew what they were hitherto. 



As both flies can be easily seen on the 

 leaves or fruit of the cherry in any in- 



Mamber* of the Wantworth Fruit Growers' Asiociation Loading a Car of Apples for the United Relief Association of Hamilton, 



an Organization That Looks After the Poor of the City. 



This aseociation ha« had a suoceseful season. Over 13,000 l)airelK of appliw were handled, of which 2,000 were exported and the ba.lance sold in the west 

 at a good average price. The membera will receive from 75 cts. to $1.50 a barrel picked on jround accordine to the commercial value of their apples 



from No. 2 Qreening-s to No. 1 Spys. 



281 



