Earthworm Hazards

First posted on 03-04-2007

Before you toss out the rest of those Canadian nightcrawlers you bought to catch those fish that weren’t biting, you might want to consider this: non-native earthworms are causing headaches around the world.

That’s right. The lowly, local earthworm, friend to gardeners, farmers and fisherman are in jeopardy of being killed off by their out-of-the country cousins. According to New Scientist, earthworms native to the United Kingdom are “wrecking the ecosystem” in parts of Minnesota, where earthworms are non-native. By dragging leaves and forest debris deep into their burrows, these worms are destroying the normal 10 to 15 inch undergrowth of soil.

This results in much denser soil which makes it harder for trees to root and easier for deer to eat sapplings. Wildflowers have even disappeared from some areas.

Worms are tougher than moles to erradictae, too. Once they’ve settled in, their undergound lairs provide plenty of protection. Conservations in Minnesota have tried electrocuting the soil with little effect.

The southeastern U.S. is also facing earthworm incursion as an Asian worm with a voracious appetite moves so fast through the forest litter “you can almost hear them.” Common earthworms just don’t stand a chance against this creature.

It is not known what, if any, affect out-of-towner earthworms are having in the Ozarks. Here, the most common imported bait of choice for fishing is Canadian nightcrawlers. Still, it may be wise not to introduce them to our woods and forest lands.