Feeding preferences of the white pine weevil, Pissodes strobi (Peck), for resistant or susceptible Sitka spruce, Picea sitchensis (Bong) Carr., were investigated using three types of laboratory bioassay. In paired-twig bioassays, fall weevils were significantly deterred from feeding up to 80% by resistant clones from four British Columbia provenances: Green Timbers, Cedarvale, Haney, and Big Qualicum. Females showed greater discrimination than males. Spring weevils were deterred from feeding by clones from the Green Timbers and Big Qualicum provenances by up to 60%. Fall males were more consistently deterred than spring males, suggesting that some host selection occurs in the fall. Females were significantly deterred from ovipositing on twigs from one clone from Big Qualicum, and stimulated by clones from Cedarvale when given a choice. Given no choice, however, they were significantly deterred from ovipositing, but not feeding by several resistant clones. In agar-disc bioassays, spring weevils were significantly deterred from feeding by bark from the provenances of Cedarvale and Big Qualicum by up to 86%. Trees from the provenances of Big Qualicum and Green Timbers caused the most consistent feeding or oviposition deterrency and may rely on this in part as a resistance mechanism. Because not all resistant clones and provenances were deterrent, we hypothesize that these trees may employ other resistance mechanisms which could be incorporated along with feeding and oviposition deterrency into breeding for resistance.

In the genus Ephoron of Japan three species are recognized: E. shigae (Takahashi), E. limnobium sp.nov., and E. eophilum sp.nov. This study includes a key to the species, a description of each species, and maps of species distributions.

Impacts of Bacillus thuringiensis var. kurstaki (Btk) and defoliation by gypsy moth [Lymantria dispar (L.)] on native, non-target arthropods were evaluated in eastern West Virginia from 1990 to 1992. Adult and larval arthropods were collected by foliage sampling and light-trapping at 24 20-ha (50-acre) plots, representing six replicates of four treatments: unsprayed, gypsy moth absent (control); unsprayed, gypsy moth present (defoliation); sprayed, gypsy moth absent; and sprayed, gypsy moth present. Pre-treatment data were collected in 1990. In May 1991, one application of Btk was made to 12 plots at a dosage of 14.4 BIU/ha (36 BIU/acre). Post-treatment data were collected in 1991 and 1992. With few exceptions, detectable effects from Btk application were restricted to Lepidoptera. Although abundance and species richness of larval and adult non-target Lepidoptera decreased at all plots between 1990 and 1992, abundance and species richness were reduced at Btk-treated plots relative to untreated plots. Richness and abundance of some larval and adult Lepidoptera declined at defoliation plots. Although the short-term (< 1 year) impacts of Btk application on non-target Lepidoptera are negative, the long-term effects (> 1 year) of reduced abundance of gypsy moth larvae may be beneficial for some native species. Although Btk application and defoliation reduce abundance of native Lepidoptera, environmental conditions such as weather may have a greater influence on population fluctuations.

Five species of Aphthona [A. cyparissiae (Koch), A. czwalinae (Weise), A. flava Guillebeau, A. lacertosa (Rosenhauer), and A. nigriscutis Foudras] were introduced into Canada for the biocontrol of spurge. Four identification keys are provided to determine these species: a field key based on the coloration of the body and appendages, a key for males using characters of the aedeagi, and two keys for females, the first based on features of the spermathecae, the second based on those of the styli.

The relative toxicities of two formulations (Dipel WP and Foray 48B) of Bacillus thuringiensis Berliner var. kurstaki to the obliquebanded leafroller, Choristoneura rosaceana (Harris), were determined in the laboratory. The effects of application rate (BIU per hectare) and spray volume (litres per hectare) on the efficacy of Dipel WP and Foray 48B against C. rosaceana were determined in raspberry fields. Mortality of C. rosaceana increased with application rate, and decreased with an increase in spray volume. Bacillus thuringiensis exhibited significantly longer residual activity al higher application rates and at lower spray volumes. The half-life (time at which 50% of original activity remains) of B. thuringiensis ranged from 2.45 to 6.68 days, depending upon application rate and spray volume. Laboratory and field studies indicate that Dipel WP and Foray 48B are highly and equally effective in killing larvae of C. rosaceana.

Species of the Agabus opacus- and lineellus-groups, as defined by Larson (1989), are combined and revised as members of the A. opacus-group. The A. opacus-group contains 13 species, namely: A. hypomelas Mannerheim, A. vancouverensis Leech, A. verisimilis Brown, A. vandykei Leech, A. wasastjernae (Sahlberg), A. opacus Aubé, A. confertus LeConte, A. euryomus sp.nov., A. walsinghami (Crotch), A. jimzim sp.nov., A. lineellus LeConte, A. discors LeConte, and A. austrodiscors sp.nov. Agabus wasastjernae and A. opacus are Holarctic and boreal; the remaining 11 species are confined to the Cordilleran region of western North America. Character distribution does not support recognition of subspecies of A. hypomelas, therefore A. hypomelas irregularis Mannerheim is regarded as a synonym of A. hypomelas. A lectotype is designated for A. discors LeConte. A phylogenetic tree of the hypothesized relationships between the species is presented.

A key to the species of the group is included. For each species, the following information is provided: synonymy; description and illustration of taxonomically important characters; notes on relationships, variation, distribution, and ecology; and a map of North American collection localities.

The traditional subgenera of Colon Herbst containing the North American fauna are Colon s.str., Myloechus Latreille, and Eurycolon Ganglbauer. We use these and also describe Tricolon and Striatocolon as new subgenera. Identification of species in the genus Colon is taxonomically difficult because of allometric variation of external characters in males, and lack of distinctive characters in females. We present keys, illustrations, and descriptions to distinguish the known North American species. A total of 37 species names have been previously applied to Colon in North America. We designate lectotypes for Colon thoracicum Horn, C. asperatum Horn, C. oblongum Blatchley, C. dentatum LeConte, C. pusillum LeConte, C. putum Horn, C. hubbardi Horn, C. nevadense Horn, and C. liebecki Wickham. We recognize 16 names as synonyms of previously named species as follows: C. clavatum Mannerheim = C. bidentatum Sahlberg; C. complicatum Hatch = C. celatum Horn; C. decore Casey = C. thoracicum Horn; C. excisum Hatch = C. hubbardi Horn; C. femorale Hatch = C. lanceolatum Hatch; C. kincaidi Hatch = C. hubbardi Horn; C. mannerheimi Szymczakowski = C. oblongum Blatchley; C. pusillum Horn = C. dentatum LeConte; C. putum Horn = C. dentatum LeConte; C. paradoxum Horn = C. bidentatum Sahlberg; C. nevadense Horn = C. celatum Horn; C. productum Hatch = C. hubbardi Horn; C. rufum Hatch = C. dentatum LeConte; C. schuhi Hatch = C. discretum Hatch; C. serripoides Hatch = C. asperatum Horn; C. pribilof Hatch = C. liebecki Wickham. We describe 22 species as new, as follows. In the subgenus Tricolon: C. blatchleyi and C. pacificum. In the subgenus Colon: C. arcum, C. nitidum, C. politum, and C. vancouverensis. In the subgenus Myloechus: C. boreale, C. californicum, C. chihuahua, C. chiricahua, C. grossum, C. hatchi, C. hesperium, C. incisum, C. longitorsum, C. megasetosum, C. mesum, C. monstrosum, C. pararectum, C. potosi, C. similare, and C. xilitla. All these species are restricted to North America except for C. bidentatum and C. politum which are northern Holarctic. This yields 42 species recognized for the North American fauna. These beetles occur in forest, open woodland, and grassland habitats. Their larvae, biology, and food are still unknown.

The five species of Dimmockia Ashmead are reviewed and keyed. Members are mainly hyperparasites of Hymenoptera and Diptera parasitic on Lepidoptera, though they are also recorded as primary parasites of Lepidoptera. The Nearctic D. incongrua and D. pallipes are redescribed and a lectotype is designated for D. incongrua. Dimmockia marylandica Girault is provisionally removed from Dimmockia but its correct placement is unknown because the unique type is lost. The Palaearctic D. brevicornis is newly recorded from North America. Additional taxonomic features are provided for D. exorientis and D. secunda. Two African species, previously placed in Dimmockia, are transferred to Sympiesis as S. polygoniae (Risbec) comb.nov. and S. cosmopterygi (Risbec) comb.nov. A lectotype is designated for S. polygoniae. A character analysis of Dimmockia species and 21 species of Sympiesis is provided and relationships are discussed.

A new genus and species, Stipecarinata striata (Hymenoptera: Eulophidae: Tetrastichinae), is described from Japan. Its relationship to other tetrastichine genera is discussed.

The gall midge Cystiphora sonchi (Bremi) has been released and established in Alberta and other Canadian provinces as a biological control agent for the introduced weed perennial sow-thistle (Sonchus arvensis L.) (Peschken et al. 1989). Cystiphora sonchi oviposits in the expanding leaves of S. arvensis (DeClerck-Floate and Steeves 1995), where the-larvae form pustule galls, each containing a single larva. They pupate in a cocoon in the gall or sometimes in the soil after exiting from their galls. Adults are short-lived (usually 1 day or less) and do not feed (Peschken 1982). Under field conditions in Alberta, C. sonchi produces three generations a year (Peschken et al. 1989)

The western conifer seed bug, Leptoglossus occidentalis Heidemann, and the southern pine seed bug, L. corculus (Say), feed on the developing seeds of conifers causing great losses to seed crops (Koerber 1963; Connelly and Schowalter 1991; Schowalter 1996). When high populations threaten the yieldof genetically superior, high quality seed in seed orchards, chemical controls may be used (DeBarr et al. 1982). However, because even minor uses of chemical pesticides are increasingly restricted, particularly in British Columbia where seed orchards commonly interface with urban areas, damaging populations of L. occidentalis may not be controlled at all.