“My daughter found this insect in the bathroom, and I haven’t been able to stop thinking about it since. I’m trying to figure out what it is, whether it’s dangerous, and what you should do if you find one in your home.”

Where do they come from?

Honestly? The ground. I wish I were joking.

They begin life as larvae—white grubs, the kind you definitely don’t want in your garden—and they stay underground for three to four years. They take it easy down there, feeding on roots. Grass, trees, flowers—nothing is safe. That’s where the real damage happens. Not from the adults that wander into your bathroom, but from the young grubs quietly eating your plants from below.

Then, one spring, they decide they’ve had enough of underground life. They emerge, grow wings, spend a few chaotic weeks flying around, mating, laying eggs, and repeating the cycle. Their adult lives are surprisingly short—about a month above ground, and then they’re gone. It’s like watching the fastest spring break ever.

Are they dangerous?

To humans? No. They’re simply large, noisy, and a little unsettling when they fly straight at you. They don’t bite. They don’t sting. They don’t spread diseases. They just have a talent for making a dramatic entrance.

But if there are lots of them? Yes, that can become annoying. They’re especially attracted to lights—porches, windows, outdoor lamps, anything that glows. Leave a window open on a May evening, and it can feel like you’ve accidentally hosted an insect party.

The real problem is the larvae. They can destroy lawns, flower beds, and anything with delicate roots. The frustrating part is that you often won’t realize they’re there until your plants suddenly stop looking healthy.

What should you do if one gets into your house?

First of all, stay calm. Easier said than done when it’s bouncing around like a drunk drone.

Here’s what to do:

• Catch it gently. Cover it with a glass, cup, or container, slide a piece of paper underneath, and release it outside.
• Turn off unnecessary lights. If your house looks like a lighthouse at night, you’re practically inviting them in. Close curtains, dim lights, and reduce outdoor lighting where possible.
• Seal entry points. Check windows, vents, doors, and any gaps where beetles could get inside.

If they’re outside but you start seeing large numbers of them, you’re likely dealing with an infestation. Dead patches of grass, struggling plants, or lots of adult beetles often mean the larvae are feeding on roots underground.

How can you control them?

You have several options:

• Beneficial nematodes. It sounds strange, but they’re real—tiny microscopic worms that live in the soil and feed on beetle larvae. They’re widely available online and at garden centers.
• Milky spore. Another natural treatment. It doesn’t kill grubs immediately, but over time it infects them and helps reduce future infestations.
• Good lawn care. Aerate your soil, avoid overwatering, and keep your grass at a healthy height. In short, don’t make your yard the perfect breeding ground.
• Encourage natural predators. This is my favorite option because nature does most of the work. Birds, hedgehogs, foxes—and even badgers, if you have them nearby—love eating cockchafer larvae. I’ve even seen robins go absolutely crazy for them.