Jumping Worms Pose New Risk to Montana Gardens

Okay, I’ll say it right out loud… I know worms are usually a good thing. They help the soil, gardeners love them, all of that. But also? They creep me out. Which, yes, I fully realize, is more than a little ridiculous.

That said, the worms we’re talking about here aren’t your typical, helpful backyard kind. These are Asian jumping worms, and they’re a whole different story.

What Makes These Worms So Different (And Actually… Worse)

These things don’t just wiggle. If you touch one, it thrashes around like a tiny snake. I’m not exaggerating. The first time you see it, you will absolutely do a double-take… and maybe jump back a step. They’ve got this weird, smooth, light-colored band that wraps all the way around their body, and they hang out right near the surface in mulch, leaves, and topsoil.

And the soil they leave behind? It doesn’t look healthy at all. It looks dry and crumbly, almost like someone dumped coffee grounds all over your garden.

What They’re Actually Doing to Montana Soil

Here’s where it gets less “ew” and more “uh oh.” These worms tear through organic material way too fast. All those leaves and nutrients your soil needs? Gone. What’s left behind doesn’t hold water well, making it harder for plants to grow.

So instead of rich, healthy soil, you end up with something that struggles to support gardens, landscaping, and even forest growth. That’s why people are paying attention to this here in Montana. Our landscapes depend on good soil, and these worms can mess with that pretty quickly.

Why They Spread So Easily Without You Noticing

This is the sneaky part. They don’t need a partner to reproduce, which means one worm can turn into a whole problem faster than you’d think. And even when winter wipes out the adults, their tiny cocoons stick around in the soil and hatch later.

Those cocoons are basically invisible, and they hitch rides on anything… plants, mulch, compost, your shoes, your tools, even your tires. So you can accidentally bring them home without having any clue.

How They Likely Got Here in the First Place

These worms originally come from parts of Asia, and they’ve technically been in the U.S. for a long time. But lately, they’ve been spreading more into natural areas instead of just staying in contained spaces. A lot of that likely comes from moving plants and soil around, and from people using them as fishing bait and then dumping them afterward. It doesn’t take much for them to get established somewhere new.

What To Do If You See One (Even If You’re Grossed Out)

If you spot one, I know… your first instinct might be to walk away and pretend you didn’t see it. I get it. But if you can, pick it up (gloves help!) and seal it in a plastic bag, then leave it in the sun. Not glamorous, but it does the job.

Also, try not to move soil or mulch from place to place unless you’re sure it’s clean, and rinse off your gear if you’ve been working in different areas. And please don’t use them as bait or toss them near water.

Why It’s Worth Reporting

If you think you’ve found one, it actually helps to report it to your local Montana State University Extension office. The sooner they know where these are popping up, the better chance we have of slowing them down.

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So yeah… worms are usually the good guys. Even I can admit that. But these? These are the exception. And somehow they managed to be both bad for your soil and extra creepy at the same time.