Are Locusts and Cicadas the Same Thing? Here’s the Difference

I was talking to a friend recently who commented, “Locusts, cicadas…same thing right?” I did not think that sounded right and was pretty sure they were NOT the same thing. So of course, I had to go home and do a little digging to find out the answer.

Turns out, cicadas and locusts are definitely not the same thing. They aren’t even particularly close relatives in the insect world. The confusion mostly comes from the fact that people have been calling cicadas “locusts” for a very long time.

So, if you’ve ever wondered whether that incredibly loud bug buzzing in the trees is a cicada or a locust, here’s how to tell the difference.

This is a Cicada:

Cicadas and Locusts Are Different Insects

The biggest difference is pretty simple: cicadas are cicadas, while locusts are a type of grasshopper.

Cicadas belong to the insect family Cicadidae and are related to insects such as leafhoppers. They have large, clear wings, wide-set eyes and chunky bodies.

These are the guys responsible for those brown skeletal remains you find on trees and plants all summer.

When I was little, we called them “crunch bugs,” because it makes a crunching sound if you squash it in your hand.

This is a Locust:

Locusts are certain species of short-horned grasshoppers that can change their behavior and appearance under particular environmental conditions. When conditions are right and their populations become crowded, they can form enormous swarms.

Locusts actually comes in many different colors and forms, but they all resemble big grasshoppers, not fat bodied cicadas with big translucent wings.

While looking for locust photos, it’s amazing how many are mislabeled!

Why Do People Call Cicadas Locusts?

This is where the confusion gets interesting.

Early European settlers in North America encountered huge numbers of periodical cicadas emerging from the ground at the same time. The massive emergence reminded them of the biblical stories of locust plagues, so people began referring to cicadas as “locusts.”

The nickname stuck.

You may still hear people use terms such as 17-year locust or 13-year locust when talking about periodical cicadas. Those insects aren’t actually locusts at all. They’re cicadas.

What Is a Cicada?

Cicadas are the insects responsible for that incredibly loud buzzing or whining sound you hear coming from trees during warm weather.

And when I say loud, I mean LOUD. Sometimes it’s downright deafening in the summer. You don’t even want to go outside in the evening.

Male cicadas produce their distinctive sound using specialized structures called tymbals on their abdomen. They’re basically making a very enthusiastic dating announcement to female cicadas.

There are thousands of cicada species around the world, and they don’t all follow the famous 13- or 17-year schedule.

In fact, annual cicadas appear every year. Individual annual cicadas still spend multiple years underground as nymphs, but their generations overlap, so adults emerge every summer.

Periodical cicadas are different. Certain populations emerge together after spending either 13 or 17 years underground.

That’s when things can get a little crazy.

What Is a Locust?

A locust is a type of grasshopper with an unusual ability to dramatically change its behavior when certain conditions cause large numbers of them to gather together.

Normally, these grasshoppers may live relatively solitary lives. But overcrowding can trigger what scientists call a gregarious phase.

The locusts become more social and begin moving together. Huge numbers can eventually form swarms containing millions of insects.

And unlike cicadas, locusts can cause serious agricultural damage.

A large swarm can travel considerable distances while eating vegetation along the way, which is why locust outbreaks have historically been associated with devastating crop losses and famine.

Do Cicadas Swarm Like Locusts?

Not really, although a major cicada emergence can certainly look like a swarm when there are insects everywhere.

Periodical cicadas may emerge in enormous numbers, but they aren’t forming a coordinated traveling swarm like locusts do.

Cicadas emerge from the ground, climb trees and other vertical surfaces, shed their exoskeletons, mate and lay eggs.

They may cover trees, fences, houses and pretty much anything else nearby, but they aren’t banding together to travel across the countryside eating everything in their path.

Do Cicadas Eat Plants Like Locusts?

This is another big difference.

Locusts have chewing mouthparts and can consume leaves, grasses and crops. That’s what makes a large locust swarm potentially so destructive.

Cicadas have piercing-sucking mouthparts and feed on fluids from plants.

Adult cicadas aren’t going to descend on your garden and chew your plants down to nothing.

Female cicadas can, however, damage small branches when they cut tiny slits into twigs to lay their eggs. Established mature trees generally handle this without much trouble, although young or newly planted trees may need protection during a particularly large periodical cicada emergence.

How Can You Tell a Cicada from a Locust?

Once you know what you’re looking for, they’re actually pretty easy to tell apart.

A cicada usually has:

• A broad, chunky body
• Large, prominent eyes
• Clear wings that extend beyond its body
• Short antennae
• No oversized hind legs for jumping

A locust looks like a grasshopper because, well, it is one.

You’ll usually notice:

• Long, powerful hind legs
• A more elongated body
• Short antennae
• Wings folded along the body
• The familiar grasshopper shape

If it looks like a grasshopper, it could potentially be a locust. If it looks like a big bug with clear wings that’s screaming at you from a tree, you’ve probably found a cicada.

Are Cicadas Dangerous?

Despite their slightly intimidating appearance and incredible volume, cicadas are generally harmless to people.

They aren’t venomous, they don’t have stingers, and they aren’t interested in attacking you.

Their main goals during their short time above ground are basically to find a mate, reproduce and complete their life cycle.

They can occasionally mistake a person for a tree and land on you, which can be startling when you’re dealing with a fairly large insect. But they’re not hunting you down or trying to bite you.

What About Cicada Killer Wasps?

Here’s another insect that sometimes gets thrown into the cicada confusion.

Cicada killer wasps are large wasps that hunt cicadas. The female wasp captures and paralyzes a cicada, carries it back to an underground burrow and uses it as food for her developing offspring.

They’re impressively large wasps, so seeing one flying around with a cicada can be a little alarming.

But the wasp is a completely different insect from both cicadas and locusts.

Cicada vs. Locust: The Quick Answer

If you just came here looking for the short version:

No, cicadas and locusts are not the same thing.

Cicadas belong to an entirely different group of insects. Locusts are grasshoppers that can enter a swarming phase under certain conditions.

The reason people sometimes call cicadas “locusts” is largely historical, and terms like “17-year locust” have helped keep the confusion alive.

So the next time someone says, “Locusts, cicadas…same thing, right?” you can confidently say nope.

And then, if you’re anything like me, you’ll probably give them way more information about cicadas and locusts than they ever actually wanted to know.