Who’s been spitting in the field? Stick your fingers into the frothy mass to find out!
You’ll likely discover a tiny moist creature with dark red eyes. This is the nymph (or immature form) of a spittlebug.
Spittlebugs begin their lives in fall, as their mothers lay eggs in hollow plant stems. When the temperature rises in the spring, those eggs hatch into nymphs and create their characteristic spittle, also known as cuckoo spit. Spittlebugs use their syringe-like mouthpart to tap the plant’s sap. It takes a lot of this ever-so-slightly-sweet water to satisfy a growing spittlebug’s appetite. They pump around 150-280 times their own weight every day!
Despite what their name suggests, all of the excess water is excreted not through their mouth, but through their bottom. The nymphs move their abdomens up and down, forcing air into their watery excretions and creating bubbles. The bitter-tasting foam provides a moist haven from predators and from temperature extremes. After continually renewing their frothy home for a few months, the nymphs form one large bubble and metamorphose into adult froghoppers, now able to jump 100 times their body length in a single bound!
Read more neat functions of insect bottoms in the book Bug Butts by Dawn Cusick.