Pale Eggar

Systematic position: The Pale Eggar (Latin: Trichiura crataegi) is a moth belonging to the order Lepidoptera and the family Lasiocampidae. It is a well-known defoliator that affects various deciduous trees and shrubs, often becoming a significant pest in orchards and woodland edges.

Host plants: This species is a polyphagous pest with a strong preference for members of the Rosaceae family. Its hosts include hawthorn, apple, pear, plum, blackthorn, rowan, and various willow species. During periods of high population density, it can cause severe defoliation in fruit-growing regions.

Biology and life cycle: The Pale Eggar has a univoltine life cycle, meaning it completes one generation per year. It overwinters in the egg stage, with females laying eggs in clusters on twigs, often disguised by hair scales. Larvae emerge in spring during bud burst and feed until early summer. Pupation takes place in a dense, spindle-shaped cocoon attached to twigs or bark, and adults emerge in late summer or autumn.

Nature of damage: Early instar larvae feed on developing buds and flowers, directly reducing fruit yield potential. As larvae grow, they consume leaves, moving from skeletonizing to complete defoliation of the canopy. Such heavy feeding stress weakens the tree, makes it more susceptible to environmental stressors, and inhibits the formation of next year's flower buds.

Control measures: Management begins with winter pruning and manual inspection to remove and destroy egg clusters found on branches. In spring, when larvae are young and vulnerable, the application of biological agents like Bacillus thuringiensis is highly recommended. Chemical control should be limited to instances of heavy infestation, using selective insecticides that spare beneficial insects and natural predators.

• Pruning to remove infested twigs during the dormant season.
• Manual collection and destruction of overwintering eggs.
• Use of pheromone traps for monitoring adult activity.
• Application of microbial insecticides during the early larval stage.