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Campylomma verbasci (Meyer) overwinters as an egg on apple, pear, Rosa spp., and Amelanchier sp. On pear, the chief prey are eggs and nymphs of Psylla pyricola Forster and all stages of Panonychus ulmi (Koch). C. verbasci is partially phytophagous but prolonged feeding by nymphs on pear fruits caused no injury. During the summer, C. verbasci lives and reproduces as a predator–phytophage on a number of herbaceous plants. Three, possibly four, generations occur in the southern interior of British Columbia. The effects on C. verbasci populations of a number of pesticides applied to pear trees are reported.

Tetraldifon was applied to I-acre forage plots at rates of 0.01, 0.1, 0.25, 0.5, and 1.0 pounds per acre, oxythioquinox was applied at rates of 0.25 and 0.5 pound per acre. Residue samples were taken weekly throughout the growing Season. Analyses were completed by gas chromatography. Substantial residues of tetradifon persisted 93 days after initial treatment. Oxythioquinox residues from the 0.25-pound-per-acre treatment dropped below the detectable range at 50 days.