Sanitation is the key step in reducing fly numbers around barns and confinement areas. Breeding sites include wet manure, straw, decaying feed, and all combinations. Keep areas around cattle pens, feed bunks and silos well drained. Insecticide treatments will work better when used in conjunction with an ongoing sanitation program to eliminate breeding sites. Immediate spreading of manure will reduce fly development or manure piles can be covered with black plastic. Use of sawdust bedding instead of straw will reduce fly production, as well.
Residual Fly Sprays
Insecticides may be applied as residual surface sprays, non-residual space sprays, baits, manure sprays, or feed additives.
Always read and follow label instructions before applying insecticides for fly control. Treat walls, ceilings, posts, and other
fly resting sites. Spray these areas thoroughly and to the point of runoff. In order to minimize control failures due to
insecticide resistance, do not apply the same insecticide, or insecticide within the same chemical class
(particularly pyrethroids), repeatedly throughout an entire season. See product labels for use rates.
| Synthetic Pyrethroid Insecticides | Organophosphate Insecticides |
| cyfluthrin - Countdown 2 EC or Countdown 20% WP | diazinon - Dryzon 50% WP |
| fenvalerate - Ectrin 10% WDL | fenthion - Baytex 45% EC |
| lambda-cyhalothrin - Grenade 10% WP | naled - Fly Killer D |
| spinosyn | |
| Elector (Spinosad) | |
| permethrin - Atroban 25% WP or 11% EC, Ectiban 7% EC or WP, Expar, Gardstar, Insectaban, Insectrin, Overtime, Permaban, Permectrin II 10% or 25% WP | stirofos - Rabon 50% WP stirofos + vapona Ravap EC |
Do not contaminate food, water or utensils with spray. Do not treat animals directly. Remove animals from barns when using Diazinon or Baytex. One gallon of spray treats 500-1,000 square feet, depending on the type of surface (See label directions). Apply to walls, ceilings and other fly resting sites. Alternate applications of pyrethroids and organophosphates. Residual fly spray materials listed above provide control for 1-7 weeks.
Fly Parasite Release Programs
Several commercial firms offer a fly parasite release program that can be used to supplement fly control around
concentrated livestock operations. These small wasp parasites attack house flies or stable flies. The benefits of
parasite release programs in livestock operations have not yet been proven. Several parasite species are available.
Spalangia nigroaenea attacks house flies and stable flies in feedlots. Parasites in the genus Muscidifurax attack house
flies while those in the genus Spalangia attack stable flies. Do not buy blends of unknown species and do not buy
shipments of Nasonia vitripennis, a species that has been ineffective in midwestern feed lots.
See ENTFACT 502-
"Biological Control of Flies".
Fly Traps
Large numbers of flies can be caught in baited fly traps but the traps do not cause any significant reduction in total fly numbers.
In addition, this approach does nothing to eliminate fly breeding sites. Electrocuting light traps may reduce house fly
and stable fly numbers in closed buildings.
Contact sprays, fogs, or spaces sprays provide rapid but short-term control of flies present during treatment. Repeat as needed. Do not contaminate feed or water. Animals may be present during application but do not apply space sprays directly to livestock. In order to minimize control failures due to insecticide resistance, do not apply the same insecticide, or insecticide within the same chemical class (particularly pyrethroids), repeatedly throughout an entire season. Alternate applications of pyrethroids (permethrin, pyrethrins) and organophosphates (naled, dichlorvos). See the label for use rates.
Contact Sprays, Fogs or Space Sprays
| Dibrom 36% EC or 1% RTU (naled) |
| Ectiban 5.7% or Permectrin II (10%) (permethrin) |
| Pyrethrins + synergist |
| Vapona Feedlot Spray 43.2% EC (dichlorvos) |
Fly baits can be scattered where house flies congregate to provide some temporary reduction in numbers. Never use baits where cattle or other domestic livestock can eat them. Place baits in areas where flies congregate, such as window sills or doorways. Baits alone will not control fly populations. They should be used along with sanitation and other insecticidal methods (e.g., residual and space sprays). Baits containing the active ingredient methomyl include Apache, Golden Malrin Fly Bait Plus, and Tailspin. Dipterex 1% Bait contains trichlorfon.
Manure sprays kill fly larvae that are developing in treated areas. They are recommended where manure cannot be removed on a 7 to 10 day schedule. Apply at a rate of approximately 1 gal/100 sq. ft. to kill maggots. Do not spread treated manure onto crops not listed on the insecticide label. Apply sprays at rates that wet the manure surface, it is not necessary to soak the manure. Repeat treatments as necessary but no more often than every 7 days. Rates to use in per 25 gallons of water include: 1 quart _ Larvadex 5% SC (cyromazine) 4 lbs _ Rabon 50 WP or 1 gal 24% EC or 1 gal _ Ravap 28.7% EC .