Name: Oak Marble Gall
Scientific name: Andricus kollari
Nature Stars: 50
About: The oak marble gall is caused by a tiny gall wasp called Andricus kollari. It can be found on oak twigs.
How to identify: The galls are hard, woody marble-like balls on the oak twigs.
Fantastic fact: The closely-related Andricus fecundator causes Artichoke Galls on oak buds.
Photograph credit: Isidro Martínez