The humble earthworm

Perhaps the most important creature in our ecosystem is the earthworm. If we were to make the earthworm disappear, what effect do your kids think it would have? It may surprise your children to know how vital this common garden creature is to our existence.

The anatomy of a worm

First, let’s take a look at an earthworm. It has no legs and no kind of skeleton. It is a long pink tube like creature that wriggles along using its’ muscles and very tiny hairs for grip. Having no skeleton or exoskeleton it supports itself using fluid filled sacks inside its’ body.

The worms body is made up of segments called annuli. The segments are covered in tiny hairs that help them move.
Which end is the head of a worm?

It may not be clear but the earthworm does have a head and a tail and food only goes in one end and out the other. It can wriggle itself in either direction so just how can you tell which end is which? Adult earthworms develop a ring near their head containing their sex organs, however all earthworms are both male and female.

Children can identify which end of the worm is its head by looking for the ring.
Why are worms important?

What makes this creature so important is the relationship it has with our soils and the plants that grow in it which we rely upon. Plants require soft, airy, free draining soil for their roots to grow and spread in. Earthworms help to create this soil by their movement through it. Some earthworms move left and right and others move up and down. When they move in the soil they break up where the soil is compacted and they leave tiny tunnels behind them. These tunnels allow air into the soil and also help water to drain away quickly.

However, even more important than their movement is their eating habits. Plants rely on nutrients within the soil that their roots can get to. For organic matter on the surface to decay and the nutrients to wash down to the roots would take a long time and be inefficient. Earthworms improve this process greatly by eating the decaying organic matter such as fallen leaves from the surface and excreting those nutrients down in the soil. The earthworm digests its’ food similar to a bird. It consumes some food but also consumes earth, best is sandy soil, to grind the food up in a gizzard. When the food has been completely broken down it passes through the worm and comes out the end as a fine rich soil.

Without the earthworm doing such an important job of maintaining our soil it couldn’t support as much plant life as it does now. Over time without the worms the soil becomes more difficult to manage and even to grow crops in, a situation faced by rural smallholders in India.

A great outdoor activity for kids on a rainy day is earthworm hunting. If you know of an area with plenty of worm casts then it’s a good bet you’ll find worms there in the rain. Try looking under some rocks too. Your kids may want to know why earthworms come out when it rains. The answer is, earthworms breath through their skin but their skin need to be wet for them to breath. When it rains it means they can go outside and explore whilst still being able to breath. Take a bucket and if you catch a few, put them in your plant pots and beds at home to help improve your soil.

We hope you enjoy going on a worm hunt with your kids. Please share with us on social media the worms you catch.