Face fly control.

Face flies ( Musca autumnalis DeGeer) became numerous in the northern half of Illinois during the summer of 1959. Large-scale residual treatments of farm premises and animals were not effective in controlling face flies. Repellent treatments with R-326 (di- n -propyl isocinchomeronate) or Tabatrex (di- n -butyl succinate) gave a practical level of control. Treatments consisting of 1% to 2% dimethoate and/or 0.1 to 0.2% DDVP in a syrup bait applied to the foreheads of cattle at an average dosage of 3 ml. per cow eliminated most of the face flies.