Apple leaf midge

The apple leaf midge (Contarinia mali) is a small insect belonging to the Diptera order and the Cecidomyiidae family. The adult insects are tiny midges that do not cause direct mechanical damage to the tree, but their larvae are considered significant pests capable of impairing the growth and development of apple trees.

The primary host for this pest is the apple tree. The midge exhibits a high degree of host specificity, targeting young leaves during their most active growth phase. In cases of high infestation levels, the pest can affect large areas of apple orchards and nurseries, causing stunted growth in young saplings.

The life cycle of the midge is closely synchronized with the phenology of the host plant. Larvae overwinter in the soil within protective cocoons. In early spring, during the budding period, adults emerge. The females lay eggs in the folds of young, developing leaves. Upon hatching, the larvae feed on plant tissues, causing the formation of distinct galls or leaf rolling.

A hallmark sign of infestation is the deformation of leaf blades: the edges of the leaves roll inward, forming tight curls or tubes. Within these structures, the larvae remain shielded from external environmental factors and predators. Affected leaves eventually turn dark, desiccate, and drop prematurely, which weakens the tree and reduces the formation of future flower buds.

• Cultivating the soil in tree basins to disturb and destroy overwintering larvae.
• Collecting and disposing of infested fallen leaves throughout the growing season.
• Applying systemic insecticides during the green tip stage and immediately post-bloom.
• Encouraging natural predators and parasitoids that feed on midge larvae.
• Monitoring adult activity using yellow sticky traps in the orchard.