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Fourteen species, six genera, and three families of Neuroptera were found in Georgia and Kansas pecan tree canopies. Chrysoperla rufilabris (Burmeister) was the most numerous green lacewing collected in both areas. Chrysoperla carnea Stephens was the second most abundant green lacewing collected. Micromus posticus (Walsh) and Hemerobius humulinus L. were the two most commonly collected brown lacewings in both regions. Green lacewing populations were 6 to 11-fold larger in Kansas than in Georgia. Brown lacewing populations were slightly larger in Georgia than in Kansas. Green lacewing seasonal incidence was similar in both areas, with the late season peak occurring 2 to 3 wks later in Georgia than in Kansas. Brown lacewing seasonal incidence varied considerably between regions and years. Coniopteryx westwoodi Melander was the primary microneuropteran species collected. In Kansas, pesticide applications had significant effect on lacewing populations in some years but not others. Carbaryl applications had greater effect on population levels than phosalone.

Five insecticides, some in different formulations, were tested for their effects on predator populations and plant bugs in cotton fields. The materials fell into 4 groups according to toxicity to predators: (1) high toxicity: fenthion emulsifiable concentrate (EC) and trichlorfon EC; (2) moderate toxicity: trichlorfon ultra low volume (ULV); (3) low toxicity: dimethoate, disulfoton, fenthion ULV, and propoxur; and (4) limited toxicity: trichlorfon 50% SP. The sensitivity of the predators to the insecticidal applications were in the following order: (1) high sensitivity: Orius insidiosus (Say) and Hippodamia convergens Guerin Meneville; (2) high 10 moderate sensitivity: Coleomegilla maculala (Dc Geer): (3) moderate sensitivity: Nabis roseipennis Reuter, N. alternatus Parsley, N. americoferus Carayon, Geocoris punctipes (Say), and Chrysopa spp.; (4) low sensitivity: Scymnus spp. and the spider complex. The spider complex was much less sensitive to insecticidal applications than were the other predators. The best plant bug control was obtained with dimethoate and fenthion EC. Dimethoate appeared to be much less toxic to the predator populations than fenthion EC.

Studies were conducted during 1966, 1967, and 1968 in the south Delta of Mississippi to determine the seasonal incidence of the major predaceous arthropod populations subjected to an integrated control program utilizing one early season insecticide application and late season insecticide applications as needed. The fluctuations in population of the different predator groups varied from year to year; the population peaks rarely occurred on the same week in consecutive years. Population levels varied considerably from year to year, as well as from week to week. The great majority of the predator groups and species were present primarily in early season. Only one species, Chrysopa rufilabris Burmeister, was primarily a late-season predator.