Cicada vs Locust: How to Tell Them Apart

Sound is your number one clue. When you hear a loud buzzing or almost electronic whining call that might last all afternoon, you are hearing a cicada. That sound comes from specialized drum-like muscles on their abdomen. Locusts, which are really grasshoppers, chirp or click in short bursts, more like background noise. Once you spot the insect, look at the eyes. Cicada eyes bulge outward prominently on both sides of the head, almost like they're staring at you. Grasshopper eyes are smaller and flatter. Finally, check the wings. A cicada at rest holds wings in a steep tent shape over its back. A grasshopper keeps its wings flat or angled along its sides. These three tells, in order, will solve the mystery almost every time you encounter one of these insects in the wildlife around you.

Cicadas typically measure one to two inches in length with a stocky, barrel-shaped body. Their abdomen is thick and rounded, built around those sound-producing organs. Grasshoppers and katydids often reach one to three inches but have a more angular, stretched-out frame. Cicada bodies are compact and sturdy, with a blunt head. Most cicadas are brown, black, or tan. Grasshoppers vary much more, from green to brown to red, and their legs are built for jumping. A cicada's legs are short and often hidden beneath the wings, while a grasshopper's back legs are long and muscular. When you pick up a cicada, it feels heavy for its size. A grasshopper feels lighter and springier.

Both cicadas and grasshoppers live across the entire United States. Cicadas appear in every state and are especially loud in the Midwest, South, and mid-Atlantic regions. They prefer trees and shrubs, coming out in late summer and early fall when the heat softens. You can hear them calling from oak, pine, and elm trees. Grasshoppers are found everywhere too but favor open grasslands, fields, and meadows. They thrive in the West and Great Plains where grass is abundant. In the Illinois wildlife region and throughout the Midwest, both insects coexist, but cicadas dominate the sound in late August and September. Grasshoppers are louder in mid-summer and early summer months.

Cicadas are poor fliers and often seem clumsy when moving. They spend most of their time either calling from one spot on a tree or slowly crawling along branches. When you approach, they rarely jump or fly away. Most cicada species are silent for most of the year because their nymphs spend years underground feeding on plant roots. Adults emerge in late summer, mate, and lay eggs that start the underground cycle again. To learn more about wildlife insects, you can compare their life stages. Grasshoppers and katydids are active jumpers. They flee when threatened, using their powerful legs to escape. They feed openly on grass and leaves, making them easier to spot. Grasshoppers make sounds throughout the summer and early fall by rubbing their legs or wings together. Grasshoppers also lay eggs in soil but have shorter underground times.

Start with sound. If you heard a loud, continuous buzzing or electric whining that lasted minutes or hours, you heard a cicada. That sound is unmistakable once you know it. If you heard short chirps, clicks, or ticking sounds, you heard a grasshopper or katydid. Next, look at the setting. Were you near trees in a neighborhood or forest? Cicadas prefer trees. Were you in an open grassy field or meadow? Grasshoppers are your answer. Check the time of year. Cicada season peaks in late August through September in most states. Grasshoppers sing through the summer and early fall. Finally, if you see the insect, note the eye size and leg length. Big bulging eyes and short hidden legs mean cicada. Small eyes and long powerful legs mean grasshopper. Use these clues in order and the mystery solves itself.

The biggest mix-up is the name itself. In the US, 'locust' historically referred to swarming grasshoppers that devastated crops. The term got applied to cicadas by mistake in some regions, especially the South. True locusts are African grasshoppers that swarm; North American grasshoppers do not swarm like that. Another myth is that cicadas are harmful pests that damage trees. Most cicada species are harmless to trees. A few species lay eggs in thin twigs causing minimal damage, but cicadas do not eat leaves or bore into wood. Another false belief is that cicadas make noise for mating calls that only males hear. Actually, cicadas sing so loudly that many animals, including predators, locate them by sound. Grasshoppers are often blamed for crop damage along with cicadas, but it is grasshoppers that actually feed on crops and garden plants, not cicadas.