Mexican bean beetles, Epilachna varivestis Mulsant, were marked with rubidium by allowing larvae and adults to feed on foliage of bean plants treated with a rubidium chloride solution. Detection of rubidium was effected by atomic absorption spectroscopy. Adults which had fed for 4 days on rubidium-chloride-treated plants then transferred to untreated plants contained elevated levels of rubidium up to 34 days. The presence of rubidium was not detectable in the progeny of treated beetles at levels significantly different from controls. Consumption of rubidium-chloride-treated foliage produced no observable detrimental effects on the beetles. The technique allowed them to acquire a relatively permanent label through their normal feeding activity.

The within-sample distributions of gallery length (GL) and egg (E) density as well as their functional relationships to the infested bole were studied in an epidemic population of the southern pine beetle in southeast Texas.

A least-squares linear regression analysis through the origin showed an average of 1.59 eggs per centimeter of gallery. GL accounted for 81% of the variation in E and thus is useful for estimating egg numbers. The density of attacking adults is unsatisfactory for predicting E.

GL and E are uniformly distributed within but not among the 100-cm2 sample disks at a given height. The functional relationship of both variables to the infested bole is adequately described by the model y = (A+Bx)exp(Cln(x−x2)), where y = GL or E per 100 cm2, x = the normalized height on the infested bole, and A, B, and C are parameters to be estimated for each set of data.

The process of resource utilization by Dendroctonus frontalis Zimmerman attacking loblolly pine, Pinus taeda L., was investigated. The quantitative relationship of attacking parent adult D. frontalis as a function of the normalized infested bole height is described by the model y = Ax(1−x)eBx. Greatest attack density occurs at the mid-bole of the tree and tapers toward the top and bottom. Gallery length (and hence eggs)/100 cm2 was independent of attack density. The relationship between gallery length (or eggs) per parent adult and parent adult density is described by the exponential decay curve y = AeBx, indicating that gallery length and egg population density are controlled by a density dependent compensatory feedback process operating instantaneously. Further support for the mechanism was obtained by analyzing the gallery length per parent adult at different locations on the infested bole. The relationship is described by the model y = [AeBx]/[x(1−x)] and indicates that gallery construction and egg population per attacking beetle increase in the upper and basal portion of the bole. The result is a uniform amount of food and space per individual of the developing population.

Within-tree larval and progeny adult populations of Dendroctonus frontalis Zimm. attacking loblolly pine, Pinus taeda L., were investigated in order to define the distribution of larvae within sample units (100 cm2 disks of bark) and to describe the functional relationship of both larvae and progeny adults to the infested portion of the tree bole.

Larvae and progeny adults were sampled over the infested bole of the 50 trees. Two separate measures of progeny adults were obtained. The first measure was taken just prior to emergence from the tree and the second measure was obtained by rearing the insect until emergence from the sample disks was completed.

Larvae were found to be uniformly distributed within the total disk. The functional relationship of the larvae and the two measures of progeny adults to the normalized height on the infested bole was described by the two parameter nonlinear model y = Ax(1−x)eBx.

Highest larval density along the infested portion of the tree bole occurred just below the center and tapered abruptly towards the base and gradually towards the top of the tree. The density of progeny adults on the other hand was greatest just above the center portion of the infested bole and tapered abruptly towards the top and gradually towards the base of the tree. Both measures of progeny adults produced curves of virtually the same shape. However, the density of progeny adults was substantially less in the samples which were reared indicating that mortality agents continued to act on the population until emergence from the tree.

Efficient methods are described for mass rearing, picking and spreading in the field millions of aphids. The originality of the method lies in the use of a powder that prevents aphids from sticking to the equipment or to each other, and makes them a flowable substance that can be spread with a special apparatus.

Traps baited with the codling moth, Laspeyresia pomonella (L.), sex pheromone, trans-8, trans- 10-dodecadien-1-ol, were evaluated for their suitability in a pest management program in an area of high host abandonment. Modifications in trap design, trap condition, or pheromone cap type resulted in variation in male moth catch. In commercial orchards the necessity of both interior and perimeter traps is indicated. Reduction in pesticide sprays was obtained in two of the four orchards monitored, but utilization of traps in a pest management program is hampered by several factors including orchard design, grower attitude, and considerations of cultural practices.

The mass production of Nosema fumiferanae spores using second, third, and fourth instar larvae of Choristoneura fumiferana is described. In general, second instar larvae inoculated with 2 × 105 spores per millilitre of suspension resulted in a maximum spore yield of 1.3 × 108 spores per larva. A spore concentration of 2 × 107 reduced larval weights and increased larval mortality.

The addition of copper to an artificial diet greatly improves growth of the house cricket, Acheta domesticus (L.). Adding zinc improves growth in the presence of added copper, but not in its absence, indicating an interaction between the two trace elements. Reproduction is always ’normal’ with added copper in the diet. Zinc added at a low level will support ’normal’ reproduction, but not at high levels. Survival is poor without added copper in the diet. It is suggested that the minimum growth requirements for zinc and copper are a total of 23 μg/g diet and 14 μg/g diet respectively.

Vitamin K1 added to a basic diet for the house cricket, Acheta domesticus (L.), significantly improves growth of male and female larvae. Growth is significantly better with 18.7 μg K1/g than it is with an equimolar amount of vitamin E. Unlike vitamin E, however, vitamin K1 is without effect on reproduction. Vitamins K3 and K5, and coumarin, have no effect or a slightly inhibiting effect on growth, and no effect on reproduction.

Observations of behavior and dissections of hosts were carried out to investigate the ability of Apanteles melanoscelus Ratzeburg (Hymenoptera: Braconidae) to distinguish between parasitized and nonparasitized gypsy moth larvae, Porthetria dispar (L.) (Lepidoptera: Lymantriidae). Fewer host examinations occurred and fewer eggs were laid in hosts which had been parasitized 0–9 days previously than in those which had never been parasitized. However, superparasitism occurred readily especially when few unparasitized hosts were available. By dissecting hosts which were parasitized more than once it was possible to investigate competition between supernumerary parasitoids. First instars are eliminated by some mechanism (possibly active combat), and older parasitoids eliminate younger ones.

The birch casebearer, Coleophora fuscedinella Zeller, has five larval instars in northeastern North America, but commonly only four in insular Newfoundland. The occurrence of four larval instars in Newfoundland represents the omission of either the third or the fourth instar. Local Newfoundland populations may have five larval instars, but the late-developing larvae of these populations have only four larval instars. Head capsule width can be used to identify instars but case characteristics are recommended because the bimodality of third instar head widths can cause confusion.

The majority (about 94%) of birch casebearer larvae, Coleophora fuscedinella Zeller, abandon the leaves in the fall and attach their case to the bark surface at spurs, at the base of buds, and at twig crotches. Casebearer populations were studied in six white birch, Betula papyrifera Marsh., stands of 3 m to 6 m in height. An average of 50% of overwintering population of the birch casebearer occurred within 50 cm of the crown periphery of the middle half of the crown. This proportion was the same at the three population densities studied: 2,000, 10,000, and 20,000 cases per tree. Intra-tree distribution differed significantly between stands and between years and was modified when there were more than 3,000 larvae in a tree. However, the relation between log10 (cases + 1) at midcrown and the whole tree was consistent and usually explained more than 85% of the variance. For all population densities, the number of casebearers in the tree could be estimated from a sample of the crown. To preserve the form and aesthetic value of trees, the sample should comprise spurs or crotches and not a crown sector as used in this study.

Field studies of male sex attraction rhythms in Argyrotaenia velutinana and five other lepidopterous species reveal that the diel periodicity was modified by ambient temperature. The temperature near the mean hour of attraction appeared to be the most important environmental parameter correlated to the shift in rhythmicity.

Pseudoxenufens forsythi n. gen., n. sp. of trichogrammatid wasp from Ecuador is described and phoresy in the Trichogrammatidae is discussed.

The amount of damage to apples caused by the bugs Atractotomus mali (Meyer) and Campylomma verbasci (Meyer) is largely related to the density of the bug population and to the apple variety. Bug numbers can be reliably measured by a ’hatching’ method, and preventative insurance spraying can be avoided where indicated.

A study was made of the developmental biology of two parasite species that attack the eggs of Rhodnius prolixus. The gregarious encyrtid Ooencyrtus trinidadensis has a life cycle of 14 days, from egg to adult. The larvae, which hatch after a 42 h incubation, are attached to the egg chorion during the first and second instars. The solitary scelionid Telenomus costa-limai has a longer life cycle (20 days), but its eggs hatch after only 17 h, and its first-instar larva is equipped with large mandibles. It is possible that this free larva is better equipped for elimination of multiple or supernumerary parasites than that of O. trinidadensis. The characteristic features of the larvae of each parasite species are also described.

Codling moth populations in six orchards in the Okanagan and Similkameen valleys of British Columbia were monitored for 2 seasons with traps baited with trans-8, trans-10, dodecadien-1-ol, the sex pheromone of the codling moth, Laspeyresia pomonella (L.). Sprays were applied if traps within the orchard captured two or more moths per trap per week during 2 consecutive weeks. Traps installed in neighboring orchards minimized male moth influx. A 43.1% reduction in the number of required cover sprays for codling moth control was obtained over a 2-year period compared with a standard three spray program. Fruit injured by codling moth in monitored orchards varied, but was less than 1% in all but one orchard.

Pre-mating behavior of male gypsy moths was investigated in 0.2 ha circular plots containing from 0 to 72 virgin females/plot in untreated areas and in areas treated with an aerial application of 20 g/ha microencapsulated disparlure. Male moths in both treated and untreated plots oriented initially to trees, not directly to females. Mating was disrupted in treated plots but males continued search behavior. No anemotactic behavior was evident in either treated plots or untreated plots with females. In untreated plots, male moths were not caught on sticky panels (panels suspended at 2, 4, and 6 m) higher than pheromone baited traps set at 2 m. In treated plots, equal number of males were caught at all panel heights and in baited traps at 2 m. Previous mating and pheromone exposure histories of males did not affect the response of these males to traps baited with 4–5 mg of disparlure in untreated plots. In a test of the relative attractiveness of a cotton wick and a new laminated bait dispenser in Johnson traps, traps baited with the laminated dispenser had a greater male moth catch/male contact to trap than the traps baited with the cotton wick. Not all males contacting the Johnson trap were caught. A mode of action for disparlure as a disruptive agent in the long range sexual communication system of gypsy moth is proposed.