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To effectively monitor forest tent caterpillar (Malacosoma disstria Hubner) populations, the use of synthetic sex pheromones to trap adults was evaluated in outbreak and nonoutbreak population levels. Three pheromone blends were field-tested, consisting of 1) (Z,E)-5,7-dodecadienal, 2) 100:1 (Z,E)-5,7-dodecadienal: (Z,Z)-5,7-dodecadienal and 3) 100:1:10 (Z,E)-5,7-dodecadienal: (Z,Z)-5,7-dodecadienal: (Z)-7- dodecanal. The tertiary blend (3) was superior for capturing forest tent caterpillar moths, and was best able to resolve population density levels. Lures dosed with 11 μg or less of either the binary (2) or tertiary blends failed to capture moths at nonoutbreak population levels, while lures dosed at 390 μg gave the highest mean trap catch and the lowest rate of zero-captures.

Previous research has shown that, in freely moving laboratory rats, the odors of benzyl alcohol, camphor, carvacrol, isopentenyl methyl sulfide, 2-propylthietane, salicylaldehyde, trimethylthiazoline, and xylene (plus other compounds) elicit high amplitude bursts of roughly 20-Hz waves (beta-waves) in the olfactory bulb and pyriform cortex. Since all these compounds are effective antifeedants in a variety of small herbivores, a more extensive test of the effect of the odor of a variety of antifeedants on pyriform cortex activity in meadow voles (Microtus pennsylvanicus) was undertaken. A beta-wave response was reliably elicited in the vole pyriform cortex by the odors of isopentenyl methyl sulfide (a component of fox odor), 2-propyl thietane (a component of stoat odor), and xylene but not by the odors of 29 other compounds. The results indicate: (a) that there are clear interspecific differences in the olfactory reactions of the pyriform cortex and (b) that not all antifeedants elicit beta-waves in the pyriform cortex.