Preventive Spraying Schedules for Dairy Farm Fly Control

Fly control was improved on dairy herds and in barns by making the first insecticide application before flies were numerous and repeating at reduced intervals to prevent fly build-up between applications. On herds, weekly applications of 0.5 to 1% Ciodrin®, ( al pha -methylbenllzyl-3,hydroxy-erotonate dimethy1 phosphate). 0.5 to 1% Sevin® (1-naphthyl- N -methylcarbamate), or 0.25% Co-ral ( O.O -diethy1 O -3-chloro-4-methyl-2-oxo-2H-1-benzopyran-7-yl phosphorothioate) at 1.2% to 1.4 pints per animal, provided good control of, or prevented severe infestation by, stable flies ( Stomoxys calcitrans (L.)), face flies, ( Musca autumnalis DeGeer, and horn flies ( IIaematobia irritans (L.)) when applications were started before the flies were numerous. In barns, house fly ( Musca domestica L.) control was greatly improved over that of previous years by applying 1.25% dimethoate or 1% ronnel at 4- and 2-week intervals, respectively, and making the first application of the season before flies were noticeable.