Nature Table: Cuckoo spit

The blobs of frothy bubbles that appear on grasses and flowering plants during the summer are not the spittle of cuckoos.

They first appear in late April or early May, at the same time as the first cuckoos start calling, which seems to be the origin of the name, and persist into the late summer. They are produced by a small sap-sucking insect called a frog-hopper.

Frog hoppers come in shades of green and brown and have oval bodies and protuberant eyes so they bear some resemblance to tiny frogs. The adult insects also hop — in fact they may be able to hop further than any other animal, relative to their size.

They can travel 70cm in a vertical direction, and even more horizontally.

The cuckoo spit is produced by the larvae, which also suck sap and, when they have extracted the nourishment they require from it, excrete it in the form of bubbles which build up around their bodies to keep them moist and protect them from predators.