These button shaped galls are caused by a tiny wasp, Neuroterus numismalis.  The underside of the oak leaves can be completely covered, each one containing a single wasp larvae. The galls fall to the ground when the leaves fall and overwinter in the ground.  Although it can look as though the leaves have been overwhelmed, the number of galls doesn't have an effect on the tree.   

Silk Button Galls on Oak

SKU: H4WHW0002
£20.00Price
  • A4 photo print on a  black background without  a mount. Price includes standard UK postage - postings overseas will vary - please email jo@haven4wildlife.co.uk for more details