Why are worms important?

You may not think they're the most attractive creatures, but worms play a vital role.

These fantastic burrowing creatures are the living, breathing engineers of the underworld. They eat and recycle organic matter to keep our soil healthy.

The intricate network of tunnels that earthworms create is extremely important too. In fact, Charles Darwin said: “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.” Strong praise indeed!

So why are worms so important?

1. They recycle nutrients

Worms are hungry little creatures and have the capacity to eat their own body weight in food every day!

Amongst other things, their diet consists of:

• dead plants,
• fallen leaves,
• fungi, bacteria and
• even dead animals.

When they eat, worms break down and recycle this organic matter within the soil. This naturally fertilises the earth and packs it with vital nutrients.

The little mounds you sometimes see on top of the soil are called worm castings (essentially, worm poo!) and are the end product of this recycling process.

Their casts can contain 5 times more nitrogen, 7 times more phosphorus, and 1000 times more beneficial bacteria than the original soil that helps plants grow.

2. They improve soil structure

Earthworms loosen, mix and oxygenate the soil as they burrow channels.

They improve the soil's structure, leaving space for water to be drained away from the surface and stored in the soil.

Research has shown that soils without earthworms can be 90 percent less effective at soaking up water. This means more water run-off, which can lead to erosion and flooding.  

Worms don’t like living in very poor-quality soil. To survive, worms need moist soils that contain enough organic matter for them to feed on. So, by digging up a spadeful of soil and counting the number of worms, farmers can get a pretty good idea of their soil’s health.

3. They repair damaged soil

Worms can also help clean up contaminated land by enhancing ‘bioremediation’. This is when micro-organisms break down environmental pollutants and turn them into non-toxic molecules.

By wriggling and burrowing, worms' movements spread these micro-organisms around the soil.

So, while they have a reputation for being dirty – they clean up fairly well!

4. They provide a food source for other important species

As important as they are alive, worms are also very important in the food chain.

They provide an important protein-rich source of food for other species like birds, hedgehogs and frogs.

Our underground allies are pretty amazing. Protecting these animals is crucially important to help protect the health and balance of nutrients in the soil.  

Find out more about the unsung heroes looking after our soil.  

• Help protect the heroes under our feet

  Did you know that earthworms are in critical decline? Help us campaign for farming systems that preserve their habitats and food sources and works in harmony with nature.

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