Plant Galls are abnormal growths on a plant caused by parasites, for instance other plants, fungi, insects or mites. The gall provides both shelter and food or nutrients for the invading organism.
Galls caused by insects or mites
The galls shown below are mostly caused by gall wasps although other animals cause them too (the last two by gall mites). You are unlikely to find the very small gall wasps but some of the galls are very common and easy to spot. Many have complex life-cycles with two distinct alternating generations. Most of the galls shown below contain the larvae of the agamic or female-only generation. These don’t need to mate but will lay eggs that cause a different gall containing the sexual generation, ie males and females. The galls below all grow on oak trees unless stated.
Photos on this page by Peter Hunnisett
Footpaths - 3 July
All paths are now dry but some of the less walked paths are getting a bit overgrown, so shorts may not be a good idea.