Xylella fastidiosa is a disease caused by a bacterium which is moved from one plant to another by small sap-sucking insects such as the spittlebug. Spittlebugs, also known as froghoppers, produce a frothy spittle called cuckoo spit to hide from predators and the froth is a sign that the insect is feeding on a plant.
Xylella arrived in Europe six years ago, devastating olive groves in southern Italy and spreading to other countries in the EU, including parts of France and Spain. The UK is clear of the disease but is on high alert. If found in the UK, all host plants within 100m would need to be destroyed and there would be immediate movement restrictions on some plants within a 5km radius for up to five years.
According to the Royal Horticultural Society, Xylella has 563 different host plants worldwide and it could affect native tree species such as oak, ash and sycamore, as well as garden plants like rosemary and lavender.
Scientists at the University of Sussex want to learn what kinds of plants spittlebugs feed on, what habitats they occupy and where they are in the country and they are asking members of the public to help record sightings of spittle and spittlebugs across the UK. The results will be used to map the distribution of the insect so that, if Xylella does enter the UK, predictions can be made about how likely it is to spread and how quickly.
Sightings can be reported at https://www.brc.ac.uk/irecord/xylem-feeding-insects.
Further information about the survey and the insects can be found at https://www.xylemfeedinginsects.co.uk/
There is a more complete article at https://www.bbc.co.uk/news/science-environment-48383730