EFSA delivers advice on pine pitch canker and the oriental chestnut gall wasp

EFSA’s Plant Health Panel (PLH) has published scientific advice on two plant pests detected recently in Europe. In one opinion, the Panel considers the risk of pine pitch canker caused by the fungus Gibberella circinata, and in another opinion, the risk posed by the oriental chestnut gall wasp, Dryocosmus kuriphilus. The European Commission asked EFSA to evaluate risks posed by these pests for the EU and to identify and evaluate the effectiveness of possible risk management options.

Based on a review of scientific literature and analysis of climate suitability, the Panel concludes that both pests have the capacity to establish and spread further in areas vulnerable to these pests, in particular in some areas of Portugal, Spain, Italy and France. Temporary controls have already been introduced by the European Commission to prevent further introduction and spread of both pests in Europe. EFSA’s scientific advice was requested to help the Commission consider permanent measures.

Pine pitch canker
Present in countries such as the United States, Japan, Korea and South Africa, Gibberella circinata is one of the most devastating diseases of pine and Douglas fir trees. In Europe, reports of outbreaks of pine pitch canker have come recently from Spain, Portugal, France and Italy. Pitch canker enters unaffected areas through contaminated seeds, wood materials and ornamental plants such as Christmas trees. Trees infected with Gibberella circinata grow slowly and suffer serious branch damage. The effects of this pest could be very significant in pine-growing areas of certain regions of Portugal, Spain, France, Italy and Greece.

The Panel concludes that in the absence of measures to protect plant health, pine pitch canker is very likely to take hold and spread across vulnerable areas in Europe. Its potential impact could be massive as pine plantations and forests in the endangered areas cover over 10 million hectares.  According to the Panel, the spread of this disease in the European Union is most effectively prevented by limiting the movement of seeds, plants, wood, soil and machinery from infested to non-infested areas.

• Risk assessment of Gibberella circinata for the EU territory and identification and evaluation of risk management options  

Oriental chestnut gall wasp
The oriental chestnut gall wasp, indigenous to Asia but now also present in the United States, affects chestnut trees. In autumn, the wasps lay eggs in the tree buds. In spring, feeding larvae cause swellings, called galls that disrupt leaf development. The pest slows plant growth and reduces chestnut production. The oriental chestnut gall wasp is introduced to new areas mainly through the planting of infested chestnut plants.

Following its introduction into the Piedmont region (northern Italy), the oriental chestnut gall wasp has now been detected in most regions of Italy and has been reported in France, Slovenia, Switzerland and Hungary. The Panel concludes that areas of chestnut fruit production in northern Portugal, northern Spain and south-west France are particularly at risk. In order to help reduce the risk of introduction and spread of this pest EFSA recommends that all chestnut planting material should be certified as free from the pest.

• Risk assessment of the oriental chestnut gall wasp, Dryocosmus kuriphilus for the EU territory and identification and evaluation of risk management options  

Both scientific opinions were developed in line with the Panel’s new guidance document on a harmonised framework for pest risk assessment and evaluation of pest risk management options

• Guidance on a harmonised framework for pest risk assessment and the identification and evaluation of pest risk management options by EFSA