Holly leaf miner - Plant Pests

Holly leaf miner, this fly belongs to the leaf miners; group of insects that eat away mesophyll.

Characteristic infestation by Holly leaf miner, photo: Bj.schoenmakers - CC0 Public Domain

Holly leaf miner (Phytomyza ilicis). This fly belongs to the leaf miners (Agromyzidae); group of insects whose larvae eat away mesophyll. The holly leaf miner is found throughout Europe. Holly is its host (host plant).
In late summer and fall, the holly leaf miner build tunnels, in which the flies hibernate. In spring, the larvae eat away the mesophyll so that the mines get bigger and bigger. They then pupate to leave mines in late spring. Adult holly leaf miners also live off holly leaves, sucking plant sap from punctured cells. In late May, holly leaf miners lay eggs in the main vein of young leaves.
Holly leaf miner damage is minor. Affected leaves may dry up and fall off, but this does not adversely affect the growth of the holly.

Where to find

Holly (Ilex)

Control

Holly leaf miner damage is minor; cutting away and destroying infested foliage is sufficient.

Prevention

Provide good growing conditions and plant less susceptible (resistant) varieties.