It fascinates us as children, but as adults we are less likely to take much notice when we spot ‘cuckoo spit’ on plants. The Royal Horticultural Society (RHS), however, in conjunction with the University of Sussex and Forest Research, are making a plea to the public to report their sightings of the spittle.
So-called ‘cuckoo spit’ has nothing to do with the bird, apart from the fact that it is often seen around the same time as the cuckoo’s call is heard during spring. The substance is secreted by a small bug known as the spittlebug, or froghopper.
Where a blob of cuckoo spit appears, a tiny insect will be residing inside. It tends not to harm the host plant, but the potential problems lie in the fact that the spittlebug is one of a number of insects that feed on plant xylems. Such insects can spread xylella fastidiosa – a bacterial plant disease that kills plants by blocking the supply of water from roots to leaves.
Xylella fastidiosa has not yet been detected in the UK, but in continental Europe, the spittlebugs have unwittingly helped spread the disease, resulting in the loss of millions of olive trees across France, Italy and Spain.
Though the spittlebug is a disease carrier, the insects do not usually damage the plants they live on. If gardeners wish to remove them, they may do so via hosing with water or simply wiping away; an insecticide is not required.
If you want to report cuckoo spit seen when relaxing on your Outback reclining chairs, you can do so here.