Published online by Cambridge University Press: 31 May 2012
Orchex-796 oil and Volck Supreme oil at 2.5 gal per acre gave equal commercial control of adults and nymphs of the pear psylla, Psylla pyricola Foerster, on Anjou pears. Control was better at 5 gal per acre but at this rate, both oils caused sporting and marginal burn on leaves and russet spots on the fruit of Anjou pears. The 2.5-gal rate caused slight leaf spotting, but no fruit injury.This indicates that the recommended rate of 6 gal of oil per acre for Bartlett pears cannot be used on the Anjou variety, and raises the question whether this high rate is necessary for pear psylla control.