The North American members of the genus Operophtera Hübner (Lepidoptera: Geometridae) are revised to include three species: O. brumata (L.), O. bruceata (Hulst), and O. danbyi (Hulst). Operophtera occidentalis (Hulst) is now treated as a subspecies of O. bruceata. All species are illustrated and characters to distinguish the species are given. The most useful characters for separating O. brumata from O. bruceata include the following: (1) hindwing dorsal surface with discal dot, which is almost always visible on O. bruceata but absent from O. brumata; (2) forewing colour, which is grey-brown or light brown in O. bruceata but reddish-brown in O. brumata; (3) abdomen colour, which is golden-brown to brown in western O. bruceata but brown in O. brumata; and (4) the costa of the forewing ventral surface, which is usually golden-brown in O. bruceata but brown in O. brumata. The structure of the genitalia of these two species allows hybridization between O. bruceata males and O. brumata females, but not vice versa.Hypothesized species interrelationships between palaearctic and nearctic Operophtera are illustrated in a cladogram. Maps for the distribution of each species are also included.

In 1997, larvae of the cutworm moth, Ochropleura implecta Lafontaine, caused economic damage to cranberries (Vaccinium macrocarpon Aiton; Ericaceae) on several neighbouring farms in Richmond (49° 10′N, 123°07′W), British Columbia, Canada. This is the first report of O. implecta on cranberries. Published host records for O. implecta include willow and a variety of herbaceous plants, such as clover and endive (Crumb 1956; Lafontaine 1998), but there are no reports of pest status on any crop. On the affected cranberry farms, larvae partially consumed unripe and ripe berries in July and August. On one farm, damaged fruit was downgraded from fresh fruit sales to the juice market, resulting in an estimated loss of $40 000 Can.

When male drone flies (Eristalis tenax (L.)) of the spring and summer generations stop dispersing, they settle within individual home ranges that provide them with sheltering, resting, basking, grooming, feeding, and mating sites. Away from its mating place, a resident male rarely responds to other insects. On its mating site, however, it is territorial, attacking alien species, such as bees, wasps, and butterflies, as well as conspecific intruders. Territorial duty is demanding, and resident males take rest periods outside their territories whenever they can. When prevented from doing so, either by sky conditions which confine them to the territory, or by crowding which eliminates many neutral sites, they become increasingly aggressive. Males on open, horizontal territories (e.g., in flowerbeds) are more likely to notice intruders, and therefore are more liable to attack them, than males on vertical territories (e.g., on broad-leaved shrubs). The aggressiveness of E. tenax has social and ecological ramifications beyond its own species, since bees may stop foraging and aphidophagous syrphids may not oviposit in places where drone flies are exceptionally active.

The palearctic cutworm, Apamea ophiogramma (Esper), is reported from North America for the first time. Four specimens were collected at a light trap in Langley, British Columbia, in 1989, 19 in 1990, and 38 in 1991. Descriptions of wing markings and genitalic characters that distinguish A. ophiogramma from the nearctic Oligia fractilinea (Grt.) are provided.

In field studies of pheromone-mediated mating disruption of lepidopteran pests, there are several ways to determine if mate location has been disrupted. One indirect method is to count the number of males caught in sticky traps baited with synthetic pheromone. A reduced catch in pheromone-treated plots relative to control plots shows that males were unable to find the source of synthetic pheromone and suggests that mating has been disrupted. More direct methods are: (1) to count the number of males attracted to sticky traps baited with virgin females; or (2) to assess the incidence of mating of (a) feral females collected in light-, bait- or other traps, (b) females caged with males in pheromone-treated areas, or (c) virgin females placed in the field and later retrieved. Females may be tethered with thread to non-sticky traps or partially dealated and placed on a “mating table” from which they cannot escape.

Blackheaded fireworm (Rhopobota naevana (Hbn.)) mating can be disrupted by pheromone components released from spiral polyvinyl chloride (PVC) dispensers in large field plots on cranberry (Vaccinium macrocarpon (Aiton) (Ericaceae)) farms. The main pheromone component ((Z)-11-tetradecen-1-ol acetate (Z11-14:Ac)) or a blend similar to natural pheromone (Z11-14:Ac, (Z)-11-tetradecen-1-ol (Z11-14:OH), and (Z)-9-dodecen-1-ol acetate (Z9-12:Ac)) was released from PVC dispensers into 0.8-ha plots on cranberry farms. Regardless of the treatment, free-flying males in treatment plots located fewer than 5% of individually caged virgin females, whereas mate location in most control plots ranged from 14%–75%. Location of pheromone lures loaded with 1.0 mg of the three-component blend was reduced in both treatments, but not to the same extent as was location of females. The magnitude of mating disruption indicated by 0.01-mg lures was similar to that indicated by caged females. Estimated release rates from dispensers loaded with Z11-14:Ac alone were linear and similar in both years of the study, declining from 575–720 mg/ha per day to 175–220 mg/ha per day after 100 days. Three-component dispensers placed in the field in July 1994 showed a steeper decline in release rates of Z11-14:Ac and a change in component ratios from 6.2:2.5:1 to 8:2:1 (Z11-14:Ac: Z11-14:OH: Z9-12:Ac) over the 60-day release period. After one season of mating disruption, the number of eggs and the number of foliar samples with larval feeding shelters were not consistently reduced in treatment plots. Mated females may have dispersed into the plots and oviposited. PVC dispensers effectively disseminate pheromone for mating disruption but are labor-intensive to use. In the cranberry system, their use might be limited to research plots and isolated farms of <8 ha.

Pseudaletia unipuncta (Haw.) males, experimentally deprived of hairpencils (male-specific scent organs), were less acceptable to females than were intact males. The degree to which females discriminated against males lacking hairpencils depended on the experimental protocol. When females were placed with males before scotophase onset, they tended to evade repeatedly and/or terminate genital contact with hairpencil-less males before eventually copulating, although this tendency was not statistically significant. When males were introduced after females had initiated calling, females refused hairpencil-less males significantly more often than intact ones. The incidence of copulation by hairpencil-less males was also lower than that of intact males, significantly so in one of the two populations tested. Neither copulation duration nor the dimensions of the cuticular portion of the spermatophore were correlated with the presence of hairpencils. Yet in all cases, females that mated with hairpencil-less males were more fecund and laid more fertile eggs than those mated to intact males. Hairpencil eversion could not be seen during courtship, nor did females show any obvious change in calling behaviour in response to scent from a freshly excised hairpencil. However, gas chromatographic analysis of hairpencils showed a decrease in titre of two scent components, acetic acid and benzaldehyde, just before the moment of genital contact between male and female, indicating that the pheromone was released at this time. These results suggest that P. unipuncta male pheromone facilitates female acceptance of males. The hypothesis that male pheromone carries information about the quality of a courting male is discussed in relation to recent work on arctiids, nymphalids, pierids and pyralids. An appendix of lepidopteran species possessing male scent structures is included.