A leafminer is any insect that completes at least a portion of its life by living and feeding inside plant leaf tissue. In most cases, the larvae feed on the leaf tissue between the upper and lower tissue (epidermis) of the leaf. The feeding damage of a leafminer can appear as irregularly shaped blotches or blisters, or as winding tunnels. The mining damage reduces the leaf area and interferes with nutrient translocation. Most leafminer infestations do not cause enough damage to adversely affect plant health and vigor, but severe infestations can cause leaves to be unsightly or defoliate.

In light infestations on small trees or shrubs, leaves with mining damage can be hand-picked and destroyed to reduce the infestation and improve plant appearance. Since the larvae live in a protected location inside the leaves, leafminers can be difficult to control. Therefore, systemic insecticides can be used for more effective control of leafminers.

For chemical control recommendations, consult the Insect and Plant Disease Control Manual, UT Extension Publication 1690, found here. Please contact your local Extension office for specific pesticide recommendations.