Expert Answer

Q: What do you suggest for fly control in dairy barns? I have been using a Pyrethoid and IGR. I am looking for an effective option roughly priced equivalent. Any Suggestions?


Nuisance and biting flies in and around dairy farms can cause significant stress to cattle which can result in reduced milk production.  Fly populations around dairies develop in decaying organic matter or areas with moist manure.  For this reason, insecticides cannot be the only tool in your dairy farm fly control program.  It is imperative that proper sanitation, weed management, and moisture control be a part of your plan to reduce fly populations around dairy buildings.  Your local extension agent and local associations are great resources for sanitation recommendations and best practices.


Dairy Farm Fly Control - Choosing an Insecticide and Options to Consider

When selecting an insecticide for use in your fly management program, some of the things you should consider are:

  • Fly Species (Most common around dairies: House Fly, Little House Fly, Stable Fly, Face Fly)
  • Label instructions
  • Required application equipment
  • Cost

Some options include:

Residual fly sprays applied to surfaces in and/or around buildings will control adult flies that come in contact with a lethal dose. These products remain active for several days.

Space sprays or knockdown products are applied as fine mists. They should be applied to areas where flies are resting. These products usually break down rapidly and do not leave a residue.

Fly baits can reduce populations of houseflies. They should be placed in areas where flies rest but kept away from feed, water, milk, and cattle. Good sanitation practices are a must for baiting programs. 

Keep in mind that there are many products labeled for controlling flies.  You should always read the label to ensure that specific areas to treat (milk parlors, milk rooms, etc.) are listed on the label.  Also, if you plan to apply product directly to or around lactating cattle they should be listed on the label.  For specific dairy fly product recommendations, please contact your local Target Specialty Products Office, or send us your comments or questions through our contact form.