Cynipid wasp gall

Description:

This gall produced by the cynipid wasp Andricus quercustozoae on oak tree branches (Quercus pubescens).

Habitat:

The wasp stitch in a young immature leaf and forces that Oak tree to deform creating around a point where the wasp has left her larva to create a form of a ball. Wasp larva will live inside and feed on young leaves and once grown-up larva will leave this tree creating a small black hole.

Notes:

In Mediterranean tradition this galls were collected to produce a powder that was used for a leather production. Coz it was so important back in 19th century existed a whole trade branch dealing with purchase from the local villages and even that was not enough so they used to trade more galls from Asia Minor. With these galls are also associated some local superstitions like the believe that you can get the long-term weather forecasts by reading the inside of that ball. Local weather experts used to say that it is gonna be a wet year if the inside was humid, and if the inside was dry, then the next year would be dry. Very easy long-term weather forecast without the help of powerful computers ;)