Arrival of plant disease spread by spittlebugs imminent, fears RHS

GARDENERS are being warned to look out for bugs that carry a disease that could wipe out many plants and trees.

The Royal Horticultural Society says a white foam on plants could be a telltale sign of the presence of spittlebugs that may be carrying Xylella fastidiosa, which has been responsible for the destruction of millions of trees in Italy.

It devastated olive farms in southern Europe and has already spread to France and Spain. The RHS and Defra have identified Xylella fastidiosa, sometimes known as leaf scorch, as one of the most pressing concerns when it comes to UK plant health.

They fear the arrival in the UK of the disease, which can destroy trees and popular garden plants, could be imminent, brought in accidentally via international trading in plants and trees.

The bacteria affects popular garden plants and trees, including oleander, lavender, oak, rosemary and flowering cherry. The “leaf burn” stops water from the roots getting to the leaves. If it is found in the UK, host plants within 100 metres will need to be destroyed and there would be immediate restrictions on movement of specified plants within a 5km radius for up to five years, which could sound the death knell for many nurseries and garden centres.

The plant charity, which is working with the University of Sussex and For- est Research, needs volunteers to help map the distribution of spittlebugs, one of the chief carriers of the disease, that can be found in gardens, meadows, grasslands and woodlands from April to late June. Infected bugs can spread the disease from plant to plant, leaving white, frothy blobs of spittle on leaves and branches. Later, the edges of leaves change colour, taking on a “burning” effect. Volunteer are being asked to report sightings of spittle, whether in their gardens or on plants elsewhere. Findings can be reported online through a site called irecord, after registering.

Volunteers will need to report their name, the location the spittle was seen and when – and most importantly, the species of plant on which it was found.

This information will help researchers understand how Xylella fastidiosa might enter and spread in the UK.

While it has not yet been found in the UK, the bacteria is causing concern among ministers and horticulturalists because if it does spread from Europe, it has the potential to affect more than 500 different plants, making it harder to eradicate than a host-specific pest.

Gerard Clover, RHS head of plant heath, said: “Xylella remains our number one concern but is not bound by the garden fence. Understanding how and where its primary vectors move is fundamental to understanding how we can stop the devastation of our gardens and environment should it arrive.”