Quick Reference

Fly Type What to Look For Best Control
Horn Flies Small (3–5mm), gather on the back and sides, bite and feed on blood Ear tags, pour-ons, back rubbers/dust bags
Face Flies Dark gray, 6–8mm, non-biting but spread pinkeye, gather near eyes, nose, and wounds Pyrethroid ear tags, pour-ons, back rubbers/dust bags
Stable Flies Gray checkerboard pattern, 7–8mm, bite and feed on blood, gather on legs, active mid-May–September Sanitation, premise spraying

Horn Flies

What to look for: Small flies (3–5mm) that gather on the back and sides of cattle and bite and feed on blood.

Control:

  • Ear tags — remove in the fall to help prevent resistance
  • Pour-ons like ivermectin — protect for about 28 days, so reapply as needed
  • Back rubbers and dust bags — let cattle treat themselves, no handling required
  • Oral larvicides in feed or mineral — stop new larvae but don’t kill adult flies

Face Flies

What to look for: Dark gray flies (6–8mm) that don’t bite but spread pinkeye. They gather around the eyes, nose, and wounds.

Control:

  • Pyrethroid ear tags
  • Pour-ons
  • Back rubbers and dust bags — let cattle treat themselves, no handling required

Stable Flies

What to look for: Gray flies with a checkerboard pattern (7–8mm) that bite and feed on blood, usually on the legs. Most common mid-May through September.

Control:

  • Sanitation — remove manure piles and other larvae breeding sites (most effective option)
  • Premise spraying — flies rest in shaded areas, so treating those spots can help