Activity Sheet - Find Out About Earthworms
Fascinating Earthworm Facts
 An earthworm's burrow can extend up to 1.5m down into the soil. Burrows help to aerate the soil, improve drainage, and aid root drainage. As earthworms digest organic material they help recycle nutrients, making them more easily available to plants.
Charles Darwin was the first scientist to take worms seriously. He realised how important they are to maintaining the health of our soils, so much so he called them “Nature’s Plough”. He estimated that each acre of ground can hold over 53,000 worms, and between them they produce up to 18 tonnes of wormcasts each year.
“It may be doubted whether there are many other animals which have played so important a part in the history of the world, as have these lowly organised creatures”
Charles Darwin.
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Earthworms are invertebrates, that means they have no bones. The body is made of strong muscles. The earthworm moves by first stretching its body, then contacting it to pull the tail after the head end. To help this it has a pair of bristles, on each segment. The bristles point backwards, so they dig into the soil and act as anchors as the earthworms body moves forward.
How to tell which end is the Head
Earthworms have no visible head. You can tell which end is the front by running you finger down its underside, feeling for the bristles (they are so small you cannot see them easily). If it feels smooth all the way, you are running your finger from head to tail. If you can feel a roughness, you are moving towards the head. |
Worms feed on all sorts of dead organic matter including leaves, fungi and even animal dung. Large worms can emerge from their burrows at night, find a dead leaf and drag it back into their burrow.
You can compost your kitchen waste using a worm bin. This uses a species of worm called the tiger worm, because it has red and brown stripes. The worms eat the waste, producing a compost high in nutrients. Worldwide there are about 3,000 species of earthworm. Of these 28 are found in the UK. The largest British species grows up to 35cm, but the largest tropical species reach over 1m!
Earthworms are eaten by many other animals. Foxes and badgers eat large quantities of worms. On a wet night worms come to the surface, and in these conditions a badger will feast on worms all night, sucking them up like spaghetti. Worms are also preyed on by moles, shrews, hedgehogs and birds such as blackbirds, thrushes and robins. Very small worms are taken by ground beetles, centipedes, frogs and toads.
The name worm comes from the Anglo-Saxon “Wyrm”, which meant any long thin animal that wriggled – it was also used for snakes and even dragons!
Build a Simple Wormery
You will need: a 2 litre plastic lemonade bottle, a plant pot filled with damp soil, crushed chalk (school chalk will do), black paper or foil, damp sand, damp soil, dead leaves, a marker pen,
- Cut the top and bottom off the plastic bottle leaving a tall cylinder
- Put about 10 earthworms into the damp soil in the plant pot. Stand the cylinder on top of the soil and fill it with alternate layers of damp soil, damp sand and very thin layers of crushed chalk.
- Mark the levels of the layers of sand, soil and chalk on the cylinder with a marker pen.
- Place some crushed dead leaves on top. Cover the bottle with black paper or silver foil to make the worms think they are underground!
- Keep everything damp (not wet) and leave for several days. After a few days remove the outer covering and see what effects the worms have had on your layers.
You could also put in green leaves, grass cuttings, kitchen peelings and other organic material - which do the worms like best? |
