Horse chestnut lace bug

Systematic position: Corythucha aesculi belongs to the order Hemiptera and the family Tingidae (lace bugs). They are small insects easily distinguished by the intricate, net-like ornamentation on their wings and pronotum, which serves as a protective camouflage against their host plant.

Host plants: The primary host for this species is the horse chestnut tree (Aesculus spp.). While they show a high degree of host specificity, the impact of their feeding can be severe on both mature trees and saplings within landscape and nursery settings.

Biology and lifecycle: The insect typically overwinters as an adult in sheltered areas, such as bark crevices or leaf litter. After emerging in spring, females deposit eggs in clusters on the abaxial leaf surface. Depending on the climate, the species can produce multiple generations per year, with populations often peaking mid-summer.

Nature of damage and economic importance: The lace bug extracts plant sap through specialized piercing-sucking mouthparts. This feeding results in characteristic stippling or bleaching of the leaves. Severe infestations cause early leaf drop, reduced photosynthesis, and overall decline in tree health, which significantly diminishes the ornamental value of the host plant.

Protection measures: Integrated pest management (IPM) is crucial for controlling this species:

• Implementing horticultural oil sprays to target nymphs and egg clusters early in the season.
• Applying systemic insecticides as a soil drench or trunk injection for persistent infestations.
• Sanitation practices, specifically removing and destroying infested leaf debris to break the wintering cycle.
• Monitoring canopy health during the early growth stages to ensure timely intervention before the population reaches an economic threshold.