Pear rust mite

You will see fine russetting or bronzing on pear leaf surfaces and fruit as pear rust mites feed on plant tissues. Tiny eriophyid mites cause small, roughened areas to develop on fruit, reducing marketability. Heavy infestations may cause leaf damage and premature drop. These microscopic four-legged mites are barely visible without magnification and are difficult to detect until damage is apparent.

Dormant season oil sprays applied before leaf emergence can target overwintering mites. Avoid preventive applications during the growing season since rust mites provide food for beneficial predatory mites. Monitor in spring and early summer to gauge population trends. Phytoseiid predator mites naturally control many populations if broad-spectrum insecticides are avoided. Maintain tree vigor.