130 



THE REPORT OF THE 



No. 19 



There are many broods during the season, so that their increase is very rapid. 

 The adult flies are smaller than the house-flies. They congregate in masses 

 about the base of the horns, on the flanks, and on the belly, just outside the 

 reach of the tail or head of the aflSicted animal. 



For several years it has been observed that oils or greases rubbed on the 

 affected parts will give relief for several days, and the flies will not come 

 near. Fish oil is strongly recommended and has been used by many owners 

 of stock. The addition of crude carbolic acid in the proportion of one table- 

 spoonful to one quart of fish oil increases its effectiveness. 



This past summer I had an opportunity of testing the eifectiveness of 

 kerosene emulsion solution against the Horn-fly. The emulsion is readily 

 made and in the usual way, and was applied by means of a small hand spray 

 pump. A fine nozzle was employed so that a very fine mist was obtained. I 

 found that although the emulsion gave <ilmost immeliave relief and killed 

 enormous quantities of flies that collected in the slahle, jet it was necessary 

 to repeat the operation during the worst Dortion of the season, both n^'ght 

 dnd morning. 



Unless I was present, the spraying operation was usually neglected, and 

 the flies became as numerous as ever. It became apparent to me that if the 

 stable employees about a large stock farm found it diflicalt to apply this 

 kerosene emulsion sufficiently often to keep the flies away, we need not 

 expect to have any better results in the ordinary farm stables where stock is 

 probably not as well cared for. 



Fig. 71. The Seed-corn Maggot; a, h, flies; d, maggot; h, puparium — all very 

 much enlarged. (After Chittenden, U.S. Dept. Agriculture). 



In the dairy stables of the Ontario Agricultural College Zenoleum was 

 used. It was applied with a compressed air sprayer. As it is readily made, 

 the same objections cannot be found with regard to its preparation as against 

 the preparation of the kerosene emulsion. The herd was kept free from the 

 horn-fly with but two or three applications per week, and the herdsman is 

 enthusiastic concerning the merits of this preparation. 



Again, the use of the compressed air sprayer makes the operation a very 

 simple one, and with the general introduction of such sprayers, we may hope 

 to have less fear for the Horn-fly in the future. 



