An investigation was carried out into the condition of a 5 year old planting of C. sativa grown for nut production on a farm woodland site by plant health officers and scientists from the Forestry Commission in November and December 2011.
The area was planted with approximately 300 trees supplied from another EU member state in 2007. The investigation revealed that numerous trees had signs of cankering and had died back to the root collar, with some re-sprouting below the cankered region. All these symptoms were indicative of C. parasitica. Forestry Commission scientists carried out microscopy studies of the fruit bodies that were submerged in the bark of the cankered material. The fruit bodies and the spores were consistent with C. parasitica and pure cultures of the fungus were subsequently obtained.
Molecular diagnostic techniques were used to amplify DNA sequences from the ITS rDNA operon of the fungus and these matched exactly with sequences of C. parastica held in GenBank. A statutory Notice has been served to uproot all Castanea sativa plants and to burn these on site. 3 km surveys of all surrounding woodland are currently being carried out to determine the extent of any symptomatic C. sativa.
All field staff and individuals working for the owner of the site will adopt biosecurity measures that will prevent further spread of this harmful organism. Action will be taken to contact recipients of plants for planting from the same source. A follow-up investigation will determine whether the organism is affecting C. sativa elsewhere in the UK. The recent finding will help to our annual surveillance undertaken in connection with the UKâ€™s Protected Zone status.