It's this time of year when we have lots of what is commonly referred to as cuckoo spit on the campanula persicifolia and verbena bonariensis that are growing on our plot.
I'm not sure why the white frothy substance is called cuckoo spit. It certainly has nothing to do with cuckoos other than it often appears when cuckoos can be heard calling - a sound that I heard far more frequently in the past.
The froth is actually produced by the nymph or young of a common bug called a froghopper. The froth is multipurpose. It protects against predators, not only hiding the young bug from view but it is also reputed to have a unpleasant taste - a fact that I am never likely to prove or disprove. It also acts as a temperature regulating system, insulating in cold conditions and cooling when it is hot and helps keep the creature moist.
I inconsiderately removed the froth from one individual. The photo below shows the underside of the nymph.
You can see that foam is being produced from its rear end. Looking at the head end you can see the feeding tube with which it pierces the plant. All bugs feed by piercing their prey or in this case plant stem and sucking juices.
The name froghopper is given to this creature as not only does the adult vaguely resemble a frog but it holds the record for the distance that it can jump in relation to its size. It can jump 70 cm (about 2' 4") which is about 100 times its length. Imagine being able to jump like that. I would be able to jump 155m (about 508' or the length of 16 double decker buses) and Martyn would manage 183m (about 600' or the length of 19 double decker buses) based on the same ratio!
The froth may look unsightly but neither it nor its resident causes any real problem to the plant.
I haven't managed a photo of an adult froghopper but I did feel one ping against me the other day. I think trying to photograph one is going to be a challenge.