The Living Forest (58) : Lime Nail Galls
Galls are abnormal outgrowths of plant or tree tissues and can be caused by various parasites, mostly by insects like gall wasps and gall flies, but also some fungi, bacteria and mites can be the origin.
The gall insects lay their eggs on the leaf surface and at the same time secrete a chemical that causes the cells on the leaf surface to expand and grow over the eggs forming the gall.
The larvae then feed inside the gall until fully grown, completely protected against predators, cold and rain.
Galls are not really spectacular, but some are quite colourful like these Nail galls (coming from a gall mite) growing on Lime leaves.
Dutch name : Lindenhoorntje
German name : Hörnchen-Galle
Latin name : Eriophyes tiliae