Pear leaf blister mite

The pear leaf blister mite (Eriophyes pyri) belongs to the Acariformes order and Eriophyidae family. It is a microscopic pest that primarily affects pear trees, causing significant damage by creating gall formations inside the leaf tissue, which protects it from external contact insecticides.

While the pear tree is the primary host, this mite can also infest apple, quince, and mountain ash trees. The pest resides inside the plant tissues, feeding on sap and injecting saliva that causes the plant to develop abnormal growths, commonly known as blisters or galls.

The life cycle begins with overwintering females hiding under bud scales. As soon as the buds begin to open in spring, the mites emerge and invade the young, developing leaves. Throughout the summer, multiple generations are produced, allowing the population to spread rapidly across the canopy.

Damage is characterized by the appearance of small, raised blisters on the leaves. Initially, these are light green or red, but they turn dark brown or black as the leaf tissue dies. Heavy infestations result in premature leaf drop, reduced tree vigor, and significant yield losses over successive seasons.

• Apply dormant oil or specialized acaricides in early spring before bud break.
• Prune and destroy severely infested branches to reduce the pest population.
• Use sulfur-based sprays during the growing season to control active mite stages.
• Encourage beneficial predatory mites in the orchard to maintain biological balance.
• Monitor trees regularly during the early growing season to detect initial infections.