Everything Earthworm

Do you love earthworms? Do they creep you out? Either way, there are thousands under your feet all the time.

Photo via Shutterstock

We want earthworms under our feet. They do amazing things for the environment, plus they are just fascinating animals. The next time you dig up a worm or see them on the sidewalk after the rain, remember these amazing facts.

Earthworms are a part of a big family


Some of their cousins include leeches, tapeworms and marine flatworms that breathe underwater. The earthworm belongs to the segmented part of the family tree, along with leeches.


Although we usually think of the common earthworm, there are thousands of different species all over the world – up to 7,000 different types! Some are tiny, only a few centimeters long, while others can grow to the size of snakes.


There are a lot of them


One acre of land can have more than 1 million earthworms!


They breathe through their skin


Worms don’t need lungs. Their skin is porous, sort of like a sponge. They can absorb oxygen and water through their skin. The catch is that they must stay moist. If they dry out, they can’t breathe and will die.


Their slime is important


Earthworms get a bad rap because of the slimy feel when you hold them. That slime contains nitrogen, a nutrient that helps plants grow. The slime also helps earthworms move through the soil. Think of that the next time you hold an earthworm!


They are cold-blooded


Because they don’t make their own body heat like we do, they need to stay in warm soil. In the summer, they are closer to the surface. In the winter, they burrow deeper in the ground to hibernate.


The common earthworm is not from Illinois


We have a lot of native earthworms in Will County, but the worm we see most often is from Europe. When Europeans came across the ocean, they brought their favorite plants, potted in soil of course. Our common earthworm friends hitched a ride over and into North American soil.


Earthworms are important to soil


What are you having for dinner? Earthworms love chomping down on soil. They absorb all the nutrients they need, then poop it out. Their poop, called castings by people in the know, is full of great stuff. It helps fertilize soil.


Plus, all those wormy movements create tunnels underground that break up the soil and help keep it healthy. The tunnels bring oxygen from the air and water deep underground.


Sunlight is an earthworm killer


Earthworms don’t have eyes like we do. They can only sense light or dark. It’s like when you close your eyes. You can tell if the light is on or it is pitch black, but that’s about it.


Earthworms can only handle a little bit of sunlight. After about an hour, it will paralyze them. Plus, the ultraviolet rays from the sun will dry out their skin. Do you remember what happens when their skin dries out? Right! They can’t breathe, so they suffocate and die.


Some earthworms are huge


In Australia, the giant Gippsland earthworm can grow up to 9 feet long! One South American species is called Martiodrilus Crassus, which is Latin for “worm which feeds on dogs and children.” Don’t worry, though. They eat soil, just like all earthworms, but they are massive, growing to about 5 feet long. Closer to home, the Oregon giant earthworm tops out at 3 feet. That’s the size of your teacher’s yard stick.