Confirmed finding of oriental chestnut gall wasp

by | Jun 17, 2015 | Featured Slider, Latest, News

The tree pest oriental chestnut gall wasp (Dryocosmus kuriphilus) has been confirmed in sweet chestnut trees (Castanea sativa) in a woodland in Kent.

A Forestry Commission spokesperson said:

“The oriental chestnut gall wasp has been discovered in one area of Kent.

“This is a pest that only affects sweet chestnut (Castanea) species of tree, and does not pose any risk to people, pets or farm livestock.

“We have launched an immediate investigation of the surrounding woodland and, once we have fully assessed the situation, we will swiftly take any appropriate action.”

Key facts:

  • Oriental chestnut gall wasp is a pest that affects species of sweet chestnut tree. Only European sweet chestnut (Castanea sativa) is grown in significant numbers in Britain, and no other tree species in Britain is affected.
  • The Forestry Commission is undertaking a full survey and analysis to determine the scale of the current outbreak and the potential cause of the outbreak.
  • Once we have fully assessed the situation, we will swiftly take any appropriate action.
  • Oriental chestnut gall wasp is a threat to sweet chestnuts in several regions of the world. It reduces nut production and can weaken the tree, leaving it vulnerable to other diseases.
  • The UK has Protected Zone Status against this pest, and the plant health services must be notified of all pending imports of sweet chestnut planting material before its arrival in the UK so that a proportion can be inspected.
  • As part of investigations into the outbreak, the new Observatree group of trained volunteers have agreed to help survey more widely for evidence of the pest.

A full statement has been published on our website at, and will be updated as the situation evolves. The affected woodland is Farningham Woods, near Sevenoaks, Kent.

Photo credit: Forestry Commission and Crown copyright.