Spotted lanternflies are the ultimate party crashers, and they show up in style.

They made their first appearance in the U.S.

In 2014, and since then, they've been having a blast trashing the place.

It's an ecological disaster that's spreading.

And we've been making them feel at home, giving them free rides and putting out the hors d'oeuvres.

Spotted lanternflies weren't even planning to come to this party.

So how did they get here?

They lay their eggs in clusters.

And cover them with goop that dries and cracks, disguising them as a smudge of dirt.

Researchers think their eggs hitched a ride on some decorative landscaping stones that took a Trans-Pacific cruise from China.

And nobody noticed.

Those stones with the eggs ended up in Pennsylvania.

And once spring hit, nymphs busted out.

They found themselves in a very hospitable new home.

A buffet of trees like walnut, maple, apple, peach, and cherry.

But spotted lanternflies are especially into grapevines.

They pierce plants with their sharp stilette and suck out the sap.

And they flick droplets of their sugary waste called honeydew.

Sooty mold grows on that honeydue, blocking the sunlight from the leaves, cutting off photosynthesis, and devastating the harvest.

Spotted lanternflies aren't flies at all.

They're a type of insect called plant hoppers.

As nymphs, they don't even have wings, just adorable polka dots.

And the later stages add red to the mix.

Only the adults have wings, but they're not strong flyers.

Luckily for them, we take them to fun new dinner parties.

They lay their hidden eggs on lumber and crops, and then we cart them around on trucks and trains.

Plus, we've got their favorite food from home to snack on along the way.

It's called Tree of Heaven.

We brought it here from Asia a couple hundred years ago, and it spread, especially along our roads and railway lines.

When lanternflies feed on the sap of the tree of heaven, they accumulate toxic chemicals that make them taste bad.

With time, predators and parasites back in Asia adapted to eat lanternflies anyway.

But most of the ones here just can't stomach them.

So there's no one around to keep the population in check.

With no enemies and so much good stuff to eat, the party's growing fast.

They haven't made it out to the West Coast yet, and California wine growers want to keep it that way.

USDA researchers in a lab at UC Davis are testing fumigation on lanternfly eggs.

It's hard for chemicals to kill pest eggs because they've got a protective outer shield.

But using a scanning electron microscope, researchers may have found a weak spot.

Each egg has a little trap door that the nymph inside uses to break free.

And the seal around the edge of the door is thinner than the rest of the shell.

Researchers hope they can get poison through that seal to destroy the eggs before they hatch.

Maybe the door is a way in, too.

It'll take a long time for local predators or parasites to acquire a taste and keep the lanternfly population in check.

Fumigation could buy us time, but to truly stop them, we might need to carefully introduce one of their old enemies from Asia.

Until then, be on the lookout for these destructive, but inconspicuous hitchhikers.