Eight hundred and seventy-six primary types of Ichneumonidae housed in the Canadian National Collection were examined and listed. These were contributed by the following authors: Viereck (248), Dasch (174), Heinrich (102), Walley (97), Townes (54), Provancher (51), Mason (25), Harrington (21), Sanborne (21), Loan (15), Barron (11), Porter (9), Gupta (6), Hopper (6), Gauld and Mitchell (5), Townes and Chiu (5), Brues (3), Cushman (3), Gupta and Gupta (3), Kamath and Gupta (3), Gupta and Jonathan (2), Townes and Gupta (2), Baltazar (1), Barron and Bisdee (1), Barron and Walley (1), Cresson (1), Curtis (1), Mitchell (1), Pratt (1), Slobodchikoff (1), Torgersen (1), and Walley and Barron (1).

Four emergence series were collected from a small mesotrophic–dystrophic lake in the southern Laurentians of Québec: near shore (station A, 0.3 m, shrubs and heaths), in the littoral zone (B, 0.6 m, and C, 1 m, aquatic vegetation), and in open water (D, 6 m, no vegetation). A gradient of species richness (121–34), of numbers (4622–1120/m2), of diversity (5.62–2.42 bits), and of equitability (0.81–0.48) extended from the shore to the open water. Also recognized was a seasonal succession of early synchronized species, many of which completed a second generation by late summer, and of more dispersed summer species. This pattern was best exemplified in the shore station, whereas in deeper sites, the assemblages were increasingly less structured and dominated by fewer species. Chaoborus punctipennis, a benthic insect feeding in the water column at night, tended to predominate in the outer stations and to impose its particular seasonal dynamics on the assemblage there. Chronological clustering revealed distinctive early- and late-season assemblages in all sites. A succession of distinct and temporally structured mid-season assemblages was evident at the shore station, but this pattern was obscured in other stations because of the recurrence and dominance of the same species throughout. Though these particular patterns may be restricted to the one lake studied, this approach based on a taxonomical and temporal analysis offers promise for generalizations once it has been applied to a variety of lake systems.

Fusarium attacking the roots of Douglas-firs in a forestry nursery was the focus of a computer simulation model that was tested against several years of nursery disease observations. Soil temperature, seedling growth, disease spread, and inoculum density and distribution were studied and their effects on measures to control Fusarium root rot were simulated. Interactions of these factors in space and time were examined from seedling germination to end of the growing season. The results from the model indicated that low soil temperature at the beginning of the growing season, rapid seedling growth, and reduction of disease inoculum levels in the upper soil horizons were the optimum prescription for disease reduction.

The egg parasitoid, Trichogramma minutum Riley, was distributed by helicopter over forest stands near Hearst, Ont., to control the spruce budworm, Choristoneura fumiferana (Clemens). The quality of the parasitoids in terms of emergence, proportion of females, longevity, and fecundity was not affected by aerial release. Based on monitoring with deposit cards, at 10 m above ground, the helicopter had an effective swath width of ca. 10 m. Aerial release provided an uneven distribution of deposit on 1.0-ha plots, with significantly less parasitized material reaching the outer edges of each plot than in the centre; parasitism of sentinel egg masses within the plots corresponded to the distribution of deposit. Over 50% of the released material was deposited on the ground. Drift outside the plots was generally less than 25 m, never exceeding 100 m. The extent of drift was dependent on the application technique, and to a lesser extent, wind direction. Deposit cards provided an extensive rather than an intensive sampling method for monitoring the aerial distribution of T. minutum.

Digital image processing was used to analyse chromatin distribution patterns of fat body nuclei of five populations of Dendroctonus pseudotsugae Hopkins taken from standing (UST) trees, stressed standing (SST) trees and downed (DT) trees. At the population level, chromatin distribution patterns of DT beetles were closely grouped, whereas those from the other beetles were not. Individual nuclei from the DT and UST populations could be correctly assigned to their groups with great accuracy (96% and 90%, respectively), but only 65% of the individual nuclei from the SST population could be accurately classified, the SST population was intermediate, and nuclei from many of its members resembled those from one or other of the two extreme groups. Digital image processing quickly revealed very minute differences in the distribution patterns that would be impossible to detect by conventional microscopy. This method of analysing chromatin distribution patterns, therefore, is a useful technique for identifying qualitative differences among populations long before more obvious external manifestations of the differences appear.