Willow lace bug

The willow lace bug (lat. Corythucha salicata) is an insect belonging to the order Hemiptera and the family Tingidae. It is recognized by its distinct, intricate, lace-like wing pattern, which gives the insect its common name. Adult lace bugs are small, typically measuring about 3 to 4 millimeters in length, and possess a flattened body structure that allows them to hide effectively on plant tissues.

This pest primarily infests trees in the Salicaceae family, most notably willows and poplars. However, it can also be found on various fruit trees, including apples and pears. By positioning themselves on the underside of leaves, these insects feed on the sap, creating localized colonies that often go unnoticed until visible damage appears on the leaf surface.

The life cycle involves incomplete metamorphosis. Adult lace bugs overwinter in protected areas, such as bark crevices or beneath leaf litter. As spring temperatures rise, they emerge to feed and deposit eggs in clusters on the undersides of leaves. Over a single growing season, multiple generations can occur, leading to a rapid increase in population if environmental conditions are favorable.

Damage is characterized by stippling, where feeding sites cause the chlorophyll to disappear, resulting in white or chlorotic spots. As the infestation progresses, these spots coalesce, leading to leaf browning, curling, and premature leaf drop. Severe infestations significantly weaken the tree's health, reducing its vigor and photosynthetic capacity, which may make it more susceptible to secondary stressors like pathogens.

Effective management requires a combination of cultural and chemical tactics. Cultural control includes the removal and destruction of fallen leaves and pruning of heavily infested branches to reduce overwintering populations. Chemical control involves the application of appropriate insecticides during the nymphal stages, when they are most vulnerable. Integrated pest management ensures that treatments are targeted, minimizing harm to beneficial insects while effectively mitigating the lace bug impact.

• Monitoring the undersides of leaves during the spring season.
• Sanitation through the removal of plant debris.
• Applying systemic or contact insecticides when nymphs are present.
• Maintaining tree vitality through proper irrigation and fertilization.