Plant Disease Alert – High Risk

A new strain of Xylella fastidiosa, a bacterial disease, could have a wide and damaging impact on our urban landscapes and countryside. The EU is on high alert for this disease and we must be especially vigilant in the UK.

We do not want this disease in the UK, so please make sure you are sourcing plants from disease-free sources, accompanied by a plant passport where required.

There is a new officially extended list of Xylella hosts for which plant passporting is required for all movements in the EU (not just movements out of demarcated outbreak areas) which includes plants supplied to RETAILERS as well as movements to growers.

The host list of plants is very extensive and increasing all the time, including oaks, maples, hebe, lavender, rosemary and many more popular plants for gardens, landscapes and forestry. This list will be updated online by the European Commission, as new hosts are confirmed in the outbreaks in France and Italy.

Multiple symptoms include leaf scorch, branch die-back and slow but steady decline.

A new cold tolerant strain (linked to the Xylella fastidiosa multiplex subspecies) appeared in France and Corsica recently.  Xylella fastidiosa has caused widespread damage in the USA and South America, affecting up to 35% of urban plantings in the New Jersey area and causing severe damage to citrus, coffee and olive production.

It’s not possible to accurately predict what will happen if we get a UK outbreak because of the complex interaction of climate, host species and methods of spread. But members of the horticulture supply chain should be aware of this and do everything they can to ensure that they are trading, selling and planting disease-free stock.

For more information please see the following:

secure.fera.defra.gov.uk/phiw/riskRegister/plant-health/documents/notifiable_diseases/xylellaFastidiosa2015.pdf

secure.fera.defra.gov.uk/phiw/riskRegister/viewPestRisks.cfm?cslref=12570

nature.berkeley.edu/xylella/