A bioassay method was developed for estimating persistence and rate of vertical movement of toxic residues of insecticides in soil Laboratory or field microplots of soil 15 to 45 cm deep were enclosed within a metal or plastic framework comprised of 1 or 5 cm sections which could be readily separated for bioassay. Using eggs and larvae of the cabbage maggot, toxic residues of carbofuran could be estimated at concentrations ranging from ca. 0.2 to 30 μg AI/g of dry soil. Higher concentrations were estimated from bioassays on treated soil serially diluted with untreated soil.

The North American species of the genus Olophrum Erichson are revised. Seven species are recognized, the holarctic species O. latum Mäklin, O. boreale Gyllenhal, O. consimile Gyllenhal, and O. rotundicolle C. R. Sahlberg; the eastern North American species O. obtectum Erichson, and the new species O. cascadeuse known from northern California and eastern Oregon and O. idahoense known from southern Idaho.

Lectotypes are designated for O. marginatum Mäklin (= O. consimile), O. parvulum Mäklin (= O. consimile), O. convexum Mäklin (= O. rotundicolle), and O. convexicolle LeConte (= O. rotundicolle). The following new synonymy was established: O. bernhauerianum Scheerpeltz, O. recticolle Scheerpeltz, O. recticolle curtipenne Scheerpeltz are synonyms of O. consimile; O. quesneli Hatch is a synonym of O. boreale; and O. brevicolle Bernhauer is a synonym of O. latum. All species are described and illustrated with scanning electron photomicrographs and line drawings, five maps showing the North American distribution of each species are provided, and a key is presented to aid in the identification of the species. All available records and biological data for the species are provided.

In laboratory trials, the susceptibility of Aedes euedes Howard, Dyar and Knab and Aedes stimulans (Walker) larvae to temephos (Abate®), was positively correlated with increasing temperature. Early instar larvae were more susceptible than late instars. Susceptibility differed 36 times from the fourth instars at 4 °C (24 h LC50 = 16.92 ppb) to the first instars at 19 °C (24 h LC50 = 0.47 ppb) the extremes of instar and temperature tested. The minimum recommended dosage of temephos (6 ppb) was ca. 9 times the LC90 of first instar A. stimulans and A. euedes at 19 °C. By contrast, the 24 h LC90 of 67.4 ppb for the fourth instar of A. stimulans at 4 °C was ca. 4 times the maximum concentration of temephos (18 ppb) currently recommended for Aedes spp. control. However, in simulated pool studies, satisfactory control of A. stimulans was achieved by 72 h posttreatment at the highest recommended dosage.

Studies showed that the type of damage, the timing of damage with the phenological stage of the crop, and the amount of available soil moisture influenced the growth response of spring wheat to acute levels of grasshopper damage and acute levels of artificial damage. Ground-level cutting of plants resulted in the greatest reduction in plant biomass and crop yield, while grasshopper damage and artificial stripping of leaf material did not result in as severe a reduction in either biomass or yield.

Damaged plants were not able to recover lost biomass when damage occurred any later than the early stages of tillering despite observed relative growth rates which were higher than control plants. The greatest degree of recovery occurred in study sites with the greatest amount of available soil moisture.

The most detrimental effect of damage on yield was the reduction of heads per plant and kernel weight. In most cases differences in the number of seeds per head between damaged and control plants were not evident.

Tuberculatus (Toltecallis) subg. nov. is characterized by the spiculation of the dorsal hairs of nymphs and by the basal pigmentation of the tibiae which differs from that of T. (Pacificallis). Three species are classified in the subgenus: T. (T.) mexicanus sp. n. (type of subgenus), distinguished by its long processus terminalis, T. (T.) garciamartelli sp. n. with spinal processes restricted to the two first abdominal segments and with short and thin spinal hairs on the embryo, and T. (T.) spiculatus Richards with processes on tergites I–IV and very long spinal setae on the embryo; the subspecies rebecae subsp. nov. of the last species has siphunculi and apical rostral segment longer and narrower at the base than in spiculatus s. str.

The viviparous winged form, the embryo, and the alatoid nymph are described. The sexual forms are unknown. All the species live on Quercus in the central part of Mexico between an elevation of 2200 and 2700 m.

Lygus bugs (Lygus hesperus Knight) were reared in the field on cotton and alfalfa to estimate their longevity, fecundity, and survivorship. In some tests, individuals were switched from one host plant to the other at the beginning of the adult stage.

Net reproductive rates (Ro) and innate capacities for increase (rm) were calculated for each of the three test populations and used as indices of host suitability. Females reared on alfalfa had greater Ro and rm values than those on cotton, while those switched from alfalfa to cotton at the adult molt had the lowest Ro value and an intermediate value of Rm.

Approximately 140 gynes of the paper wasp, Polistes fuscatus, were overwintered in the laboratory with their natal nest and nestmates. After a 14 day isolation period, three marked female nestmates were placed into a nesting box with three marked female nestmates from a presumably unrelated colony. Fifteen nesting boxes were constructed, each with six gynes from two different sister groups. The identities of paired gynes (spaced ≤5 cm apart) and foundresses on nests were recorded in blind observations. Sisters preferentially paired (P <.0001) prior to nesting. Of 18 foundress associations formed at newly constructed nests, 16 consisted of sister groups.

Linear regression analysis was used to estimate the developmental threshold, t0, and thermal constant, K, for all preadult stages of two laboratory colonies of the mosquito Toxorhynchites rutilus septentrionalis (Dyar and Knab). The colonies originated from Newark, Delaware and Lake Charles, Louisiana. The physiological and ecological significance of the within- and the between-population differences in the slopes of the regressions,t0's and K's, are discussed.

Mortality of neonatal Douglas-fir tussock moth larvae varied from 0% to 100% depending on the rearing temperature and duration of food deprivation. Lower temperatures apparently favor larval survival under starvation conditions. For each period of food deprivation, mortality occurs earlier as the temperature increases; this shift to earlier mortality was significant at P <.01. Some implications are discussed.

Two new species of Braconidae are described from North America. Illidops terrestris new species was reared from Elasmopalpus lignosellus (Zeller), and is the first described species of Illidops from North America. Bracon compressitarsis new species was reared from the boll weevils Anthonomus grandis Boheman and A. hunteri Burke and Cate. It is distinguished from other braconids previously recorded from boll weevils.

Recent collections (1980–1982) of winter stoneflies in southern Manitoba have resulted in the addition of five previously unrecorded species: Capnia coloradensis Claassen, C. confusa Claassen, Paracapnia angulata Hanson, Skwala parallela (Frison), and Utacapnia trava (Nebeker and Gaufin) to the nine previously recorded species. Eight of the 14 species now known from Manitoba occur in the small spring-fed streams on the east escarpment of the Duck Mountain Provincial Park. The probable zoogeographical origins and present distribution of winter stoneflies in Manitoba are explained in light of various post-glacial drainage patterns. Adults of U. trava were observed, often copulating, on the underside of the ice. They were also observed crawling away from streams with no ice cover to a distance of 50 m.

The parasite and predator component of within-tree southern pine beetle, Dendroctonus frontalis Zimmermann, mortality was investigated by mechanically excluding insect parasites and predators from the bark surface of naturally infested shortleaf, Pinus echinata Mill., and loblolly, P. taeda L., pines. Mortality caused by insect parasites and predators was determined by comparisons of five treatments that differed only in the duration of natural enemy exclusion. These natural enemies were responsible for 28.04% and 23.85% of the within-tree beetle mortality in 1978 in Arkansas and in 1979 in Georgia, respectively. Natural enemy species that arrived on the tree during the first week following mass attack by beetles caused the greatest amount of mortality.

Predator density was greater than parasite density at both locations. The majority of the predator complex arrived during the first week following mass attack by beetles, while the parasite complex arrived throughout the entire period of beetle brood development.

A linear response was found between the number of southern pine beetle prey and the number of prey destroyed per predator. A mean (± S.E.) of 4.79 ± 0.64 southern pine beetle immatures were destroyed by each individual predator.

Females of Glypta fumiferanae (Viereck) (Hymenoptera: Ichneumonidae) lived 8–28 days and oviposited 42–176 eggs if fed honey but lived only 2–5 days and oviposited 4–89 eggs if unfed. Experiments were done under near natural conditions of temperature and humidity (15°–26 °C and 50–80% R.H.). At low host densities fed adults oviposited live eggs daily and unfed adults, 10. Starved adults at low host densities lived about a day longer than those at high host densities indicating that resorption of eggs may occur in this species. General parasite and host density relationships are discussed.

Described are adults of Atylotus insuetus (Osten Sacken), A. calcar n. sp., A. utahensis (Rowe and Knowlton) and A. tingaureus (Philip) and immature stages of the first two species. The distribution of the four species in western North America is plotted and a key is provided for their separation.

For 5 days in May 1980, the drift of aquatic insects was studied in 3 streams draining bogs treated with temephos granules for mosquito larvae control, around Gagnon (51°52′ N, 68 °10′ W) in Subarctic Quebec. In the bogs the residual activity of temephos against mosquito larvae decreased from 100% to 0% in 5 days. While a control stream showed no change in drift, in the 3 streams exposed to temephos drift density was increased by an average of 6.4 × the pre-treatment level. This increase was significant for Plecoptera (11.8 ×), Ephemeroptera (4.7 ×) and Diptera (3 ×), but not for Trichoptera or other lotic insects. The increase in each order was respectively due to Podmosta macdunnoughi (Nemouridae), Baetis spp. (Baetidae), and Chironomidae. A principal component analysis separates samples taken post-treatment from pre-treatment or control stream samples (factor 1) and samples taken in the different streams (factor 2). The data suggest that temephos, when applied to bogs for mosquito control, may affect lotic insect drift in small streams draining these bogs, and that P. macdunnoughi is particularly sensitive to this organophosphorous insecticide.

Past experiments concerned with the elucidation of the daily activity pattern of male spruce budworm, Choristoneura fumiferana (Clem.), have used the response of males to virgin females as the criterion of activity. Males showed a peak response just after sunset and little activity in the early afternoon (Greenbank 1963; Sanders 1971a). Difficulty arises in interpreting such data in terms of male activity patterns. It is obvious that males are active after sunset; however, there is no way of knowing whether the reduced activity in the early afternoon is a result of changing response thresholds by the males or whether it is a result of the females releasing insufficient, if any, pheromone (see Morse et al. 1982). After the identification of the components of the female sex pheromone (Sanders and Weatherston 1976) a synthetic sex attractant was developed and the inherent daily activity pattern of male spruce budworm could be determined.

We performed a simple field experiment to determine the margin of safety for stream invertebrates for Matacil® 180 Oil Flowable, a candidate insecticide for the spruce budworm, Choristoneura fumiferana (Clem.). Matacil® 180 Oil Flowable is finely milled aminocarb suspended in summer oil.