MANHATTAN, Kan. - Livestock producers can take steps this winter that will pay off in controlling stable flies this spring, a Kansas State University scientist said.

"Spring and early summer populations of stable flies in pastures most often develop at winter feeding sites of hay in round bales," said K-State Research and Extension entomologist Alberto Broce. "When hay wasted during feeding is mixed with manure, it develops into ideal larval habitats for stable flies."

He said heavy stable fly populations can curb stocker cattle weight gain by as much as 0.5 pound per head per day during the spring and early summer.

Hay and manure ratios of 1:1 to 5:1 provide the best conditions for developing stable fly larvae, he said. So, any effort a producer can make to lessen the amount of wasted hay or to control or reduce the accumulation of the hay-manure medium will help cut stable fly production.

Several practices can help, he said, including:

  • Frequently moving the placement of the feeding tub to prevent the accumulation over one spot of the hay-manure medium;
  • Using feeders, such as cone feeders, which have been demonstrated to lower (although not prevent) the amount of wasted hay;
  • Unrolling the round bales on pastures, but not on the same site; or
  • Spreading the accumulated hay-manure medium to allow it to dry.
  • "The economic levels of stable flies in pastures appear to be of significance only during a four to six week period during the spring and early summer, but with the potential reduction in weight gain of 0.5 pound per head per day in stocker cattle, controlling them is worth the effort," Broce said.

    SOURCE: K-State Research and Extension news release.