Oriental Chestnut Gall Wasp : Observatree guides

Dryocosmus kuriphilus is a species of gall wasp native to China that is commonly referred to as the oriental chestnut gall wasp (OCGW). In June 2015 it was discovered for the first time in Britain. OCGW induces galls (distinctive growth irregularities) to form on sweet chestnut trees (Castanea sativa) which can result in a reduction of growth and fruiting. At this time, we believe that OCGW is the only insect that is forming galls on Sweet Chestnut.