The leaf-mining moth, Phyllonorycter messaniella has three generations a year. Larvae feed within the leaves during July, October, and from November to March. When fully fed, the larvae pupate within the leaf mines. By late winter, much of the foliage on a holm oak may be affected. The adult moth has brownish-white wings with a span of almost 8mm.
Mines caused by Ectoedemia heringella develop during spring and are fully formed by the end of May. The adult moth has a wingspan of 5-6 mm and the forewings are white and black in colour.