Pear scale

Systematic position: The pear scale (Epidiaspis leperii) belongs to the order Hemiptera, family Diaspididae. This species is a notorious sap-sucking pest that is well-adapted to surviving on woody perennial plants by forming a protective cover.

Host plants: The pest primarily targets fruit trees, with a strong preference for Pome fruits like pears and apples, as well as Stone fruits including plums, peaches, and apricots. It can also infest various ornamental shrubs and wild-growing relatives within the Rosaceae family.

Biology and life cycle: The life cycle is characterized by the formation of a hard, greyish scale that protects the insect. Fertilized females overwinter under the bark or in crevices on the trunk and thick branches. In spring, they produce eggs. The emerging crawlers are mobile and seek out fresh areas of the bark to settle, feed, and develop their own protective shells.

Damage and severity: By extracting sap, the scale significantly weakens the plant. Infested trees often show bark cracking, chlorosis, and stunted terminal growth. Severe infestations can lead to the necrosis of individual branches and, if left unchecked, may cause the decline or death of the entire tree, especially in young or stressed specimens.

Control measures: Management strategies focus on both physical and chemical interventions. Pruning and removing loose, dead bark can physically reduce the overwintering population. Dormant oil sprays are highly effective at suffocating females during the winter. During the growing season, systemic insecticides should be applied precisely when the crawlers are active and exposed before they establish their protective covers.