It’s fly season!! Here is the 2025 Horn Fly Quick Reference Guide. The economic threshold for horn flies on cattle is when populations reach 200 horn flies. Horn flies increase stress in cattle due to biting. Both sexes feed on cattle and take 20 to 40 blood meals per day with each feeding lasting up to 10 minutes. Effective horn fly management can result in a 15-30 pound increase in weight in stocker calves during the growing season. For more information here is a link to our publication regarding horn fly control in cattle.
https://www.uaex.uada.edu/publications/pdf/fsa-7031.pdf
