Pale brindled beauty

The pale brindled beauty (Phigalia pilosaria, syn. Phigalia pedaria) is a moth belonging to the family Geometridae. This pest is widely recognized in temperate regions for its larval stage, which can cause significant defoliation in various deciduous woody plants and orchard trees.

The larvae primarily feed on a range of host plants, including apple, pear, cherry, and plum trees. Beyond orchards, they are also frequently found on forest trees such as oak, elm, lime, and birch. Their feeding habits make them a common target for pest management efforts in both agricultural and woodland settings.

The biology of this species is distinct, as the females are wingless and must crawl up the trunks of trees to lay their eggs. These eggs remain in crevices of the bark throughout the winter, and the larvae emerge in early spring, precisely when the buds are starting to swell and open.

The damage caused by the larvae is most significant during the early spring period. They consume buds, developing flowers, and young leaves. In years of high population density, these caterpillars can cause severe defoliation, which severely stresses the trees and results in reduced fruit yield and overall growth vigor.

Integrated pest management strategies for this species include:

• Installing sticky bands on tree trunks in late autumn to trap the flightless females.
• Applying insecticides during the early larval development stage if populations exceed thresholds.
• Promoting biodiversity in the orchard to encourage natural predators, including parasitic wasps and birds.
• Practicing good orchard hygiene, including the removal of loose, old bark where eggs may hibernate.