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Significant outbreaks of saddled prominent, Heterocampa guttivitta(Walker), have been recorded in northern hardwood stands throughout the northeastern United States since 1907 and were first noted in Ontario in 1938 (Martinat and Allen 1988). The insect overwinters as a pupa beneath litter, adult emergence begins in late May and peaks in mid-June, and oviposition activity ends in early July. Consequently, the major impact of defoliation usually occurs in late summer feeding. Principal hosts are sugar maple, Acer saccharumMarsh. (Aceraceae), American beech, Fagus grandifolia(Ehrh.) (Fagaceae), and yellow birch, Betula alleghaniensisBritton (Betulaceae) (Rush and Allen 1987). Two successive years of severe (>75%) defoliation of sugar maple result in significant growth loss (Bauce and Allen 1991), and heavy mortality may occur to understory sugar maple (Grimble and Newel1 1973). The quantity and sugar content of sugar maple sap are dramatically reduced the spring following heavy (>50%) defoliation (Magasi 1981; Handy 1968). Heavy to severe defoliation may cause crown dieback and defoliation and, in concert with other stresses, may initiate maple decline (Giese et al.1964). Currently, monitoring and evaluation of saddled prominent populations must rely on egg sampling (Grimble and Kasile 1974), a time-consuming process that is inconvenient for survey personnel and landowners. A sex pheromone has not been identified for this species (nor for any other North American Notodontidae) and would be a potentially useful tool for detecting incipient outbreaks, predicting population levels, and evaluating population trends.

AbstractUsing gas chromatography and gas chromatography – mass spectrometry analyses of sex pheromone gland volatiles, we identified E- and Z-11-tetradecenals (E:Z-11-14:Aid) in an 85:15 blend of E:Zas the primary sex pheromone components of Croesia semipurpurana(Kearfott). Similar chemical analyses of sex pheromone gland extracts indicated the presence of the congeneric acetates (85:15 E:Z-11-14:Ac) and their saturated analogue (14:Ac); in addition, 85:15 E:Z-11-14:Alds were present at 5% of the acetates. The E:Z-11-14:Alds alone elicited trap capture; admixtures of saturated and unsaturated acetate analogues exhibited no significant synergistic or inhibitory effects. PVC rods with an 85:15 E:Z-11-14:Ald blend is recommended as a trap bait for monitoring population trends. It is unknown whether or not the components identified here represent the complete pheromone blend of this species; data from traps suspended 1.5 m above the ground versus those suspended 10 m above the ground suggest that future field studies may need to be conducted with traps positioned in the tree canopy.

The bluebeny maggot, Rhagoletis mendaxCurran, is a primary insect pest of low bush blueberries, Vaccinium angustifoliumAit. (Ericaceae), in eastern Canada. Eggs are laid in ripening berries and mature larvae emerge from the berries to pupate in the soil. Adult flies can be controlled with insecticides (Wood et al.1983) and (or) cultural control by bum or flail-mow pruning of bushes. Pruned plants do not bear fruit the season after pruning, and this rotation of fruit and nonfruit years is believed to reduce fly populations by limiting food availability (Lathrop 1952). Adult flies can be monitored by capture on yellow-panel sticky traps or red-sphere traps (Prokopy and Coli 1978; Wood et al.1983; Neilson et al.1984). In this study, we focused on the sex ratio of R. mendaxflies captured on baited and unbaited yellow-panel sticky traps (Pheroco® AM traps) and on the orientation behavior of flies toward wind-vane traps.

The major component of the sex pheromone of the eastern spruce budwonn was established by Weatherston et al.(1971) to be trans-11-tetradecenal. Subsequently it was found (Sanders and Weatherston 1976) that a small proportion of cis-11-tetradecenal was essential to attraction and indeed was a component of the natural pheromone. In addition Weatherston and Maclean (1974) have shown that the female sex pheromone gland contains trans-11-tetradecenol, a presumed biosynthetic precursor to the aldehyde.