ROBIN’S PIN CUSHION GALL
PLANT galls are the highly distinctive structures formed by a range of invertebrates such as insects and mites.
These gall-forming species are termed as cecidogenic species which include gall wasps of the Cynipidae family, flies of the Cecidomyiidae family and some aphids.
Galls can be found on any part of a plant from roots to seeds and fruits and consist of plant tissue, the growth of which is controlled by the gall inducing species.
It is over summer that various plant galls start to become noticeable. Galls tend to occur more commonly on plants under stress, such as very dry conditions, waterlogging or hedge cutting. Galls are found less on vigorously growing plants, and young and damaged plants tend to host larger and more numerous galls.
One familiar gall is the oak apple, which is an apple-like growth commonly found on many species of oak and can be found in June and July. These oak apples range in size from 2cm to 5cm in diameter and are formed by a species of tiny wasp biorhiza pallida (2mm to 3.5mm) laying its eggs within developing leaf buds.
On hatching, the larvae induce this abnormal growth by the oak providing both a protective habitat and food source for the developing larva.
During late summer a widespread and spectacular gall can be found on the stems of wild rose known as the “Bedeguar Gall” but more commonly referred to as Robin’s Pincushion. This gall is formed by the tiny wasp Dipoloepis rosae where the female wasp lays up to 60 eggs in a