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A complex of insects which can cause moderate to severe crop damage attacks peanuts in the North Carolina-Virginia production area. Wild species representing the seven sections of the genus Aracbis L. were evaluated for resistance to tobacco thrips (Frankliniella fusca Hinds), corn earworm (Hefiotbis zea Bodie), and potato leafhopper (Ernpasca fibae Harris) during a 3-year field study. Very high levels of resistance for these insects were identified in several species collections. Because collections in section Aracbis were among the species with the highest resistance levels, utilization of the germplasm resources to improve cultivated peanuts should be possible. In addition to evaluating species collections, 40-chromosome (A. hypogaea x wild species) hybrid derivatives were evaluated for resistance to the three insect pests plus southern corn rootworm (Diabrotica undecirnpunctata bowardi Barber). Selections with resistance levels equal to or greater than the cultivar NC 6 were made for corn earworm and southern corn rootworm. Laboratory tests of several Aracbis species indicated that a mechanism of resistance to H. zea is antibiosis. Because the levels of resistance to several insects have been greatly increased in lines of A. hypgaea, evidence exists for germplasm introgression from wild to the cultivated species of peanuts. ~

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Pesticides commonly applied to the foliage of peanuts in North Carolina were evaluated under field conditions for their effect on the twospotted spider mite Tetranychus urticae Koch. Most fungicides caused a higher mite increase than insecticides on NC 2 peanuts. When fungicides and insecticides were tank mixed or applied on alternate weeks, mite outbreaks occurred. These outbreaks were followed by severe injury to the foliage and finally defoliation and yield reductions. Among the fungicides applied only Du-Ter and Copper Count failed to cause significant mite damage even when combined with an insecticide. Since mites failed to develop on untreated peanuts following six or more mite releases during the season, it was apparent that pesticides predispose peanuts to spider mite buildup and damage.

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Requirements for establishing ladino clover (Trifolium repensL.) into pastures may differ markedly between conventional and no‐till systems. Objectives of this study were to compare effects of pesticides and seeding date on fall establishment of ‘Tillman’ ladino clover seeded with tall fescue (Festuca arundinaceaSchreb.) in conventionally prepared seedbeds and sod‐seeded into tall fescue‐dominant swards on a Typic Hapludult soil in Piedmont North Carolina. Effects of grass suppression were studied in no‐till plantings by either applying or not applying paraquat (1,1'‐dimethyl‐4,4'‐bipyridinium ion). Carbofuran (2,3‐dihydro‐2, 2‐dimethyl‐7‐benzofuranyl methylcarbamate) either was not applied or was applied for insect control at two seeding dates (early September and mid‐October) in four trials and at one seeding date (31 August) in a fifth trial. Clover stand reductions by insect and/or mollusk pests were much greater in notill plantings than in conventional plantings. Clover stands from notill seedings in late August were destroyed in one trial by slugs (Derocerus laeveMull.), but were largely unaffected in prepared seedbeds. Insecticide moderately increased clover densities and yields of September conventional plantings in three of five trials. September‐seeded clover damaged by insect and/or mollusk pests 10 to 15 days after emergence averaged 67 and 23% in no‐till and conventional plantings, respectively. Insecticide alone or with paraquat was required in September no‐till plantings to produce clover yields approximately equal to or exceeding those of the check in September conventional plantings. Mid‐October conventional plantings of clover usually failed to survive the winter due to frost heaving, yet survived well in the no‐till plantings. We conclude that insecticides are usually necessary for successful establishment of ladino into tall fescue swards in early September, but may not be needed as often in prepared seedbeds.