Oak brindle

Systematic position: The Oak brindle (Biston strataria) belongs to the order Lepidoptera and the family Geometridae. This moth is recognized as a significant defoliator in European deciduous forests and is known to occasionally reach pest status in various woody plant landscapes.

Host plants: The species is polyphagous and feeds on a wide range of deciduous trees. Its primary hosts include oak, poplar, lime, birch, and elm. In orchard settings, it can also attack fruit-bearing trees, such as apple and pear, causing significant aesthetic and biological damage to the foliage.

Biology and life cycle: The insect overwinters as a pupa within the soil. Adult moths emerge in early spring, typically between March and April. Females lay eggs in clusters on the bark. Upon hatching, the larvae feed on foliage throughout the spring and early summer before descending into the soil to pupate, completing one generation per year.

Nature of damage and pest status: The larvae cause damage by consuming leaf tissue. In low numbers, the damage is negligible; however, heavy infestations can result in significant defoliation. This stresses the host tree, leading to reduced vitality, stunted growth, and increased susceptibility to secondary pests, pathogens, and drought stress.

Control measures: Integrated pest management (IPM) is recommended for long-term control. Cultural practices include cultivating the soil around tree bases to disrupt pupation. Biological control involves using entomopathogenic bacteria or encouraging natural predators. Chemical intervention with targeted insecticides should be reserved for periods of high larval density.