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Traps baited with two types of chemical feeding attractants yielded 97 species of macrolepidoptera at three areas in Alaska (Fairbanks, Delta Junction, and Palmer). These were 16 geometrid, 1 thyatirid, and 76 noctuid moth species and 4 species of nymphalid butterflies. Potential crop pests trapped included Apamea devastator (Brace) (glassy cutworm), Xestia c-nigrum L. (spotted cutworm), Xestia smithii (Snellen) (Smith's dart), Euxoa ochrogaster (Guenée) (redbacked cutworm), and Discestra trifolii (Hufnagel) (clover cutworm). The clover cutworm was captured early in the season (May into June), while Smith's dart, glassy cutworm, spotted cutworm, and redbacked cutworm were captured in traps in mid to late summer. Many more species and greater numbers of moths were captured in traps baited with acetic acid and 3-methyl-1-butanol than in traps baited with a multicomponent floral lure (phenylacetaldehyde, methyl salicylate, methyl-2-methoxy benzoate, and β-myrcene). However, most of the geometrid moths captured (12 of 16 species) were in floral lure traps, while one species of Hadeninae (Noctuidae) and both species of Plusiinae (Noctuidae) were trapped exclusively in floral lure traps. The one thyatirid, both Catocalinae noctuid species, and most Amphipyrinae, Cuculliinae, Hadeninae, and Noctuinae noctuid species were captured in traps baited with acetic acid and 3-methyl-1-butanol. In addition, large numbers of bumblebees were captured in traps baited with the floral lure, while large numbers of yellowjackets were captured in traps baited with acetic acid and 3-methyl-1-butanol.

Certain neonicotinoids are used in cotton, Gossypium hirsutum (L.), to control various piercing-sucking pests. We conducted field studies using three neonicotinoids (acetamiprid, thiamethoxam, and imidacloprid) and an organophosphate (dicrotophos) to assess the activity of these insecticides against nontarget arthropods, particularly predators, and to determine the potential economic consequences of such activity. Mortality among populations of the big-eyed bug, Geocoris punctipes (Say), and the red imported fire ant, Solenopsis invicta Buren, was highest after thiamethoxam and dicrotophos treatments. Numbers of arachnids were consistently lower after dicrotophos treatments, whereas none of the neonicotinoids caused appreciable mortality. Total predators in pooled data from five separate studies revealed that numbers, compared with untreated plots, were reduced by -75% in dicrotophos, 55-60% in thiamethoxam, and only 30% in both acetamiprid and imidacloprid plots. Acetamiprid and thiamethoxam exhibited significant mortality against field-deposited eggs of bollworm, Helicoverpa zea (Boddie). Both thiamethoxam and dicrotophos plots exhibited bollworm numbers that were approximately three times higher than treatment thresholds (three per 100 plants), whereas numbers in untreated plots were below threshold levels. In one study on Bt cotton, a significant negative correlation was observed between numbers of predators and bollworm larvae. Results demonstrated that neonicotinoids differ in activity against predaceous arthropods and bollworm eggs and that high predator mortality can result in resurgence of bollworm larvae and additional insecticide costs.

The seasonal activity of adult elaterids (Coleoptera: Elateridae) associated with potato production was studied in Palmer, Alaska (N61.60°, W149.13°) from