Four genera and 9 species of ants were collected by pitfall traps in a spruce budworm-infested forest of northern Maine. Myrmica detritinodis and Camponotus herculeanus were most abundant. In 1977, significantly more individuals and species were trapped in dense spruce-fir stands than in either uncut residual or clearcut strips. In 1978, clearcut-strip and dense-stand means were nonsignificant for individuals and species, but significantly more individuals and species were trapped in clearcut than in uncut residual strips. Ants were active during the spruce budworm’s developmental stages. Diversity of ant species was generally greater in dense stands than in strip-clearcut areas. Individuals were distributed unevenly among species but more evenly in dense stands than in strip-clearcut areas (residual + clearcut strips). Coefficients of community (CC) and percentage similarity (PS) values indicated ant species and individuals shared forest conditions in common; however, the most dissimilar neighboring habitats (uncut residual and clearcut strips) had few species in common. Neither age of strip clearcut (1–6 years) nor litter depth had much influence on mean catches and mean number of species of ants/trap/week.

The effects of three trap variables (age, saturation, and density) on catches of male spruce budworm moths were tested using Pherocon 1CP® traps baited with synthetic sex attractant in high-density budworm populations in Maine and low-density populations in Ontario. As trap age increased, the number of moths captured decreased significantly; traps aged 2, 10, and 16 days caught an average of 5.4, 28, and 27% fewer moths than unaged traps. Traps functionally saturate and trapping efficiency diminishes in both high and low density populations after ca. 50 moths are caught, although maximum observed catch was 193 moths/day. Density or spacing of traps also affects trap efficiency. Traps spaced 5 m apart may act as a single attraction source. Interference between traps was evident for traps spaced 10, 20, and 30 m apart, while traps spaced at 40 m had the least interference. However, interference at all spacings was noted during peak moth flight in 1978 when mean catch was ca. 140 moths/trap/day.Pherocon 1CP traps can be used for detecting and monitoring spruce budworm populations; however, influences of trap age, timing of trap placement, trap saturation, spacing of traps, and lure strength should be taken into account.

Mean daily progeny production by Trichogramma minutum (“Maine strain”) was 15.2 in Choristoneura fumiferana and 10.9 in Sitotroga cerealella eggs. Total progeny production was higher in S. cerealella, but not significantly different from that of C. fumiferana eggs. Significantly more eggs were deposited by T. minutum the first day than in subsequent days regardless of host. We found no significant relationship between progeny produced by females and the day of male death as previously reported. Ratio of females:males decreased significantly with increasing age and opposition activity of the mother. The oviposition period spanned 68% of the female's life span when S. cerealella eggs were available; whereas females spent significantly less time (60%) ovipositing in C. fumiferana eggs.

Spruce budworm egg deposition spanned 27 days during both 1979 and 1980. The egg deposition curve is essentially a normal bell-shaped distribution with a slight skew to the right. Spruce budworm eggs are most acceptable to T. minutum Riley for successful parasitism during the earlier stages of host–egg development. Parasitism rates at two different temperatures (21 °C and 27 °C) were significantly greater for 1- to 3-day-old eggs than for 6- to 8-day-old spruce budworm eggs. Major reduction in host–egg acceptability occurred after the fifth day at 21 °C and after the 4th day at 27 °C.

No abstract