Xylella – what is it and what are the risks for the UK?
Xylella fastidiosa is a bacterium native to North and South America which causes serious disease in many crops including grapevines, citrus fruits and coffee.
For a long time, it was confined to North and South America but in 2013 the death of olive trees in southern Italy was traced back to xylella. Since then, major outbreaks on other ornamental plants in southern Spain, the Balearic Islands and southern France have appeared.
Inevitably, xylella infects many plant species that are popular in British gardens. Rosemary, lavender, hebe and cherry are prime examples, and it is transmitted between plants by insects which feed on their sap.
However, as xylella hasn’t yet been detected in the UK, the obvious big risk is that it could arrive on imported plants – and so the UK government and the horticultural industry are taking measures to prevent its arrival as a matter of some urgency.
The symptoms of xylella, confusingly, are identical to those caused by drought, frost damage and other diseases such as leaf scorch, wilt, dieback and ultimately, the death of the plant. This means that correct identification and confirmation of the disease requires testing in a laboratory.
However, the fact that it hasn’t yet been detected in the UK, also means that UK grown seeds and plants are very low risk, as are previously healthy plants that have been established in the garden for more than 5 years.
Of course, the converse of this is that bringing plants in from outside the UK, particularly from a region near to a xylella outbreak, carries a higher risk of infection. As proper, professional imports have to undergo inspection and follow the regulations in place, a greater risk is posed by individuals bringing home plants in their luggage where the risk is undetected and unknown. As most infected plants will show symptoms within a few years, that gives the insects plenty of time to spread it.
Currently, the UK government will implement EU regulations for the control of xylella if an outbreak is confirmed. Depending on the severity of the outbreak, these controls range from destruction of the infected plants and those in close proximity, to those within 100 miles, a buffer zone, restricted plant movement and control of insects that spread the disease.
Obviously, prevention is far better than trying to cure. By giving a high profile to the damage xylella could bring, and by educating home gardeners about the disease – especially the risk of casual imports – we can all contribute to prevent the introduction of this potentially devastating plant disease to the UK.
The Willow Wand: beautiful living art for your garden.
We provide exceptional and unique decorative willow plants. If you would like to be part of our distribution network, please get in touch.