Hawthorn Button-top Midge

The midge induces stunted and distorted rosettes in the host by inhibiting the elongation of the shoot; the rosette is formed from many (8 to 40 or more) slightly thickened and deformed leaves with reduced petioles. Many of the leaves have small green or red ligulate excrescences or projections. The midge larvae are of an orange-red colour. The gall is occasionally found on isolated plants, but infestation is more commonly in hedges, with the new growth resulting from hedge cutting being the site of high density populations. The rosettes stand out prominently against the sky. Old galls persist and new shoots grow from unaffected buds lying well behind the terminal bud.

The hawthorn button-top gall midge shows a scattered distribution throughout England, however it is an under recorded species. The gall can be controlled by spraying with insecticide at the larval stage.