Things You'll Need
- Insecticide ear tags
- Dust bag
- Spray applications
- Barn fans
Instructions
Open up all the windows and doors in any barns the cattle are being kept. Only house cattle in areas with good ventilation. Horse flies thrive on hot, musty places and are discouraged by breezes.
Install barn fans every 30 feet in the building to keep fresh air circulating. This will improve the cows' comfort and discourage horse flies.
Insert insecticide ear tags on the cattle at the beginning of June, or whenever the weather begins to get hot. Insecticide ear tags are the best method of keeping horse flies from a cow's face, where it is most vulnerable. Remove the ear tags in the fall to prevent the local fly populations from becoming resistant to it in subsequent years.
Install a dust bag with insecticide over an alleyway that the cattle walk through regularly. This hangs at an appropriate height so that it coats the animals' backs with insecticide when they walk under it. Most dairy farms will hang them over the exit of the milking parlor.
Apply spray applications to individual cattle when it appears they are heavily affected by horse flies. Have a bottle handy in the milking parlor or housing area. Take care not to spray them in the eyes or mouth.