Country matters: Sticky situation no problem for the flatulent little frog-hopper
Published 03/07/2016 | 02:30
Blobs of spittle-foam are attached to the long, winding tendrils of cleavers (galium aparine) which firmly cling with thousands of tiny hooks to passing trouser legs.
At the edge of a town, no-thing remains of a factory but a tall, red-bricked chimney that stands like a lone sentinel in a Lowry painting of matchstalk folk scurrying to work.
The surrounding ground has returned to wilderness where birds find seeding weeds and bees wild flowers. Valerian bright reds, pinks and whites are slashes of brushwork beside the docks, clovers, foxtails and ribwort plantains.
The cuckoo has been spitting on blue bugle which the medieval apothecary Culpeper recommended as a "healer of stab wounds" and which also had uses to "combat the delirious trembling" brought about by excessive alcohol consumption.
These curious blobs of foam, however, have no connection with the avian parasite which heralded summer-is-a-coming-in. Perhaps the name, cuckoo spit, came about with the birds' nest invasions and presence heard but seldom seen.
There is another life, however, within the gooey moisture, which clings to plantain stalks and grass stems. When the blob is poked, a living creature is revealed. This is the larva of a frog-hopper (philaenus spumarius), a relative of the aphid and the family ceropidae.
It got its name because it is frog-like with bulging eyes and powerful back legs and can leap away to escape danger. John Clare, poet of the English countryside, called these bugs "wood seers" or "wood prophets" as they were one of a shepherd's weather glasses. When the insect's head appears to be upward, it is a sign of good weather ahead; when downward, rain may be expected.
Cuckoo spit is produced in the same way as bubbles are blown in a common children's activity. A popular song went: "I'm forever blowing bubbles, pretty bubbles in the air." Today, bubble-blowing street performers may be seen in Dublin.
The hoppers, like aphids, suck plant sap and excess sugary fluid called honeydew is voided. This forms a film over an abdominal cavity into which breathing tubes open. Air is exhaled through the cavity to blow the honeydew into bubbles as a sticky fluid exudes to strengthen them so they will cling to the plant stems.
The naturalist Peter Marren says this is a "heroic example of insect flatulence" with a tiny animal "farting into its food".
The spit is a domed cocoon protecting the larva from predation and from drying up as it sucks its nourishment from the plant it is glued to.
The protection of the spit, however, is not totally secure. Ants are attracted to the sugary waste, and there is also a tiny wasp that can penetrate the bubbles and drag out the young hoppers which are taken to feed the wasps' own larvae. Despite the foamy protection, the perils of the weedy jungles of derelict sites and wild gardens can be ever present until torrential rains wash away insect life.
Meanwhile, ambulatory snails inch along, on a somewhat lesser cling-film menis- cus of slime than slugs, sec-ure in their habitat from shell-smashing thrushes of which there has not been a sign or a song in many a morning.