The three key lepidopterous pests of cruciferous crops, Artogeia rapae (L.), Plutella xylostella (L.), and Trichoplusia ni (Hübner) were monitored throughout the growing season at several locations in Washington and Oregon in 1986 and 1987 on collard plants. Populations of these pests differed markedly from location to location and between years. Artogeia rapae was the most abundant, P. xylostella was next in abundance, and T. ni the least abundant and on many dates it was not observed. Seven species of parasitoids were recovered and rates of parasitization varied significantly over time and among locations. Diadegma insulare (Cresson) was the most abundant parasitoid of P. xylostella. It parasitized up to 100% (range 0–100) and accounted for 74–100% of the total parasitization. Cotesia rubecula Marshall was the dominant species attacking A. rapae in Washington (0–50% parasitization) and accounted for 32–100% of the total parasitization. The only parasitoid species recovered from T. ni was Voria ruralis (Fallen) which parasitized from 0–14% of the larvae.

The immatures of eight mosquito species in six genera were collected from treeholes and artificial containers at three sites in central Missouri from May - October, 1986 - 1988. The species most frequently collected was Aedes triseriatus (Say), followed in descending order by Anopheles barberi (Coquillett), Orthopodomyia signifera (Coquillett), Aedes hendersoni (Cockerell), Culex restuans Theobald, Culex territans Walker, Psorophora ferox (Humboldt), and Toxorhynchites rutilus septentrionalis (Dyar & Knab). Larvae of Ps. ferox collected from a basal white oak treehole were the first record of this species from this habitat. Larvae of Cx. restuans and Cx. territans were collected only from artificial containers and not from treeholes. Aedes triseriatus was opportunistic with respect to tree species inhabited, with distributions roughly paralleling the relative abundance of available treeholes. Artificial containers, even when enriched with leaf litter, did not constitute an adequate mimic for treeholes when sampling Ae. triseriatus immatures.

In laboratory studies with 14 food substances, peanut butter and honey were the most attractive substances to workers of the ant Wasmannia auropunctata. In tests with 6 oils, soybean oil (once refined) was the most attractive to the workers; however, it was not significantly more attractive than tuna oil and sunflower oil. A comparison of the attractiveness of the commercial fire ant baits Amdro (hydramethylnon) and Logic (fenoxycarb) with a peanut butter standard indicated that Amdro was not significantly different; however, Logic was significantly less attractive. Field bait acceptance studies of W. auropunctata were conducted in the Galapagos Islands with the following: the fire ant baits, Amdro and Logic; the Pharaoh's ant baits, Raid Max Ant Bait (N-ethyl Perfluorooctanesulfonamide) and Maxforce Pharoah Ant Killer (hydramethylnon); and lard, peanut butter, peanut butter oil, honey, and honey:water (1:1). Results indicated that the most attractive substance to workers was Amdro; however, it was not significantly different from peanut butter, lard or Raid Max Ant Bait.

This research investigated the ability of five species or strains of parasitic nematodes to control the Colorado potato beetle, Leptinotarsa decemlineata (Say), when beetle prepupae were released on potting soil containing the nematodes. The nematodes tested were: Steinernema carpocapsae Weiser (All strain); S. carpocapsae (Mexican strain); S. feltiae (= bibionis) (Filipjev) (strain #27); S. feltiae (strain #980) and Heterorhabditis bacteriophora Poinar. Six dosage levels ranging from 10.3 to 329.2 nematodes/cm², in addition to the water-only controls, were used in these laboratory tests. Each dosage-strain combination was replicated four times with 20 prepupae exposed to each individual treatment. The five strains demonstrated 100% kill at 164.6 nematodes/cm². Except for the Mexican strain of S. carpocapsae, every strain produced over 98% mortality at 82.3 nematodes/cm². Dosage response regression equations were calculated for each strain. Although field applications probably would require higher rates to obtain the same mortality, the use of parasitic nematodes has potential for suppressing Colorado potato beetle populations. The cost or dosage rate of nematodes may have to be reduced before the control costs would be acceptable to a grower.

Mating behavior of the bronze birch borer, Agrilus anxius, was investigated under laboratory and outdoor conditions. Propensity to mate was greater for beetles more than 1-d-old. Duration of copulation tended to increase with increasing beetle age; 87% of mated females were inseminated and subsequently avoided sexual contact. Males mated more than once; previously mated males copulated sooner and for longer periods of time than naive males. Mating frequency did not influence female reproductive success.

Various bait formulations containing 0.3% or 0.6% of the fluoroaliphatic sulfone, sulfluramid, were evaluated for control of the red imported fire ant, Solenopsis invicta Buren, in field tests in Florida and Georgia. No significant differences were indicated in the effectiveness of sulfluramid baits containing 19.4, 24.4, 29.4 or 29.7% once-refined soybean oil; all gave control equivalent to that given by the hydramethylnon (Amdro^®) standard in all tests. Sulfluramid baits were slightly more effective when applied in spring or summer than in late fall. Although higher rates were slightly more effective, differences in rate of application of formulated bait or active ingredient did not significantly affect effectiveness of the treatments in any given test. Rates of 2.52 - 13.44 g/ha of active ingredient or 0.84 to 1.68 kg/ha of formulated bait resulted in population index reductions of 80–99 percent.

The effect of non-host crabgrass, Digitaria sanguinalis (L.) Scop., on potato leafhopper, Empoasca fabae (Harris) (Homoptera: Cicadellidae), utilization of alfalfa, Medicago sativa L., as host was investigated in binary choice experiments that measured oviposition and residency preference of adults. Leafhoppers preferred to oviposit and reside on pure alfalfa over alfalfa mixed with crabgrass. Successive experiments in which crabgrass was presented to leafhoppers with fewer sensory cures (i.e. tactile, gustatory, visual, olfactory) demonstrated that olfactory cues alone from crabgrass may explain the lower preference equally as well as any combination of other cues. Thus, volatile chemicals from crabgrass reduced acceptability of alfalfa for the potato leafhopper, although visual stimuli are not completely excluded. Additional experiments showed that leafhopper density, lighting, and alfalfa density all may influence leafhopper host utilization in laboratory experiments.

Survival of individually-reared immature rusty grain beetles (RGB), Cryptolestes ferrugineus (Stephens), was determined on finely cracked, medium cracked, and coarsely cracked corn maintained at 30°C and 75% RH. The study was conducted to determine whether differences in progeny production on the various particle sizes of corn (as shown in an earlier study) could be attributed to inherent differences among the various particle sizes of cracked corn in their ability to support egg to adult development of RGB. The proportion of the test population surviving (number of live adults/number of eggs hatched) was 0.76 (214/280) for finely cracked corn, 0.79 (222/280) for medium cracked corn, and 0.72 (194/269) for coarsely cracked corn. These differences in survival were not statistically significant. Thus, the hypothesis that there are differences in inherent suitability of the various particle sizes of cracked corn for supporting egg to adult development of RGB is not supported.

The sugarcane grub, Ligyrus subtropicus (Blatchley) encounters both natural field flooding and controlled field flooding by Florida sugarcane growers. Third instar larvae (grubs) of L. subtropicus were tested in various flood tests. After a five day (120 h) simulated flood, 68% of grubs survived at 18° C versus 0% at 28° C. Respiration as indicated by CO₂ production was significantly higher in grubs at 28° C in both flooded and unflooded treatments than in grubs at 18°C under similar conditions. These data indicate that grubs drown faster at higher temperatures at least partly due to increased respiration. In behavior tests conducted at water temperatures of ca. 24° - 25°C, grub populations moved upward in response to flooded conditions including 21.7% of the grubs which emerged from the soil to settle on the soil surface. Grubs became sluggish after 2 h underwater. Within 24 h underwater, all grubs were comatose (non-responsive to probing) and remained in this condition until death.

Abamectin was effective in reducing egg hatch, larval survival, adult mating behavior and oviposition of the lesser peachtree borer, Synanthedon pictipes (Grote and Robinson) LPTB, and egg hatch and larval survival of the peachtree borer, Synanthedon exitisoa (Say) PTB, in the laboratory at rates of 10 and 20 ppm. Subsequently, tests in peach orchards with comparable rates of abamectin were effective in reducing PTB populations in Peach and Taylor counties, Georgia. Although abamectin was less effective than chlorpyrifos (standard recommendation) for PTB control, it warrants consideration as an alternative for control because it is a natural product derivative and probably poses little threat to the environment.

A new species of gall midge, Putoniella gracilis (Diptera: Cecidomyiidae), is described. It infests leaves of plum and peach (Prunus spp.) in southeastern United States. The genus Putoniella is redescribed, and the new species is distinguished from its only congener, the European Putoniella pruni (Kaltenbach), also a pest of Prunus.