CONTROL EXPERIMENTS WITH YELLOW JACKET WASPS (HYMENOPTERA, VESPIDAE) INJURING CATTLE IN ISRAEL

Injuries caused by the German yellowjacket Sespula germanica F. to dry and lactating dairy cows (Bos tourus) in 5 herds in Israel were monit ored and adversely affected less than or equal to 65% of the cows. Eli mination of large alternative protein sources (placentas, sewage conta ining milk from the milking parlor!, and prebaiting with high-quality minced meat (or fish) in adequate numbers of baiting cages around the dairy farm for several days. are necessary for successful control. Sig nificant control was achieved after a shorter period of time when the dairy farm was surrounded by a smaller area of uncultivated land than by a larger area. Al some dairy farms there were significant differenc es among numbers of wasps visiting the various cage sites and signifca nt variability between baiting days. Efficient and significant control was achieved by minced meat bait containing 1.5% acephate (orthene) a nd 2% microencapsulated diazinon (Antikan). Wasps were totally repelle d by minced meat bait containing 2.25 % of a plant-derived bioinsectic ide derived from Meliaceae (Ag1000). The potential of using Ag 1000 fo r repelling yellowjackets from teats and udders of dairy cows is discu ssed.