Today is World Earth Day: What lies beneath... why it's so important not to treat soil like dirt

Earthworms

Earthworms are amazing. They drag stuff from above the soil down below the earth, bringing nutrients deep into the ground. Their tunnels aerate the ground, and their casts (earthworm poo!) are particularly important for soil health. There are up to 10,000 types of microbes in these casts, and these nourish plants and help fight plant diseases. There are many YouTube videos on bioturbation (earthworms tunnelling through soil), and they’re strangely relaxing to watch. Grab yourself a cuppa, light a scented candle and switch on some bioturbation. You will feel much better afterwards.

Activities for children

See how many earthworms you have. 

Dig a 20cm by 20cm (by 20cm deep) pit. That’s about the length of a shovel. Carefully pull the soil apart. Put it all in a tray and count the earthworms, then return them to their soil.

Springtails

If you have ever pulled a Christmas cracker, you may have found a little plastic toy that springs into the air when you push its rear end. The animal equivalent of this is the springtail — they’ve been described as the Tigger of the insect world. Springtails have a forked structure attached to their belly called a furcula, and when they need a quick getaway, they release it and bounce high into the air.

It looks as if they are popping away randomly, with little sense of direction, but in fact they have a small tube by their back legs called a collophore, which they use to direct their spring. When they are not springing around, they use this collophore to groom themselves. Their jump is enormous: up to 300 times the size of the insect. That would be equivalent to people being able to spring over skyscrapers.

I have often thought about what animal trait I would like to have if I was able to magically conjure up powers. I think I’d like a furcula. And a collophore, so I would look good too when I suddenly arrived at my destination.

Dung beetles

Dung beetles are essential in our 'fight' against poo. They also look spectacular, with shiny little bodies. There are several different types — you have probably seen wildlife films of ‘rollers’. These tiny beetles push large balls of poo. In the films, they are usually dwarfed by an enormous poo, and are pushing it up a hill, until they reach their burrow, where they push it in. They have enormous strength and perseverance, and watching them makes the rest of us feel very inadequate.

These beetles are not found in Ireland. But we have ‘tunnellers’ here. These dig tunnels, fill them with dung and lay eggs in it. Moving the dung around also helps to disperse seeds, as well as bringing nutrients underground, which benefits plants.

A third type of dung beetle is the ‘dweller’, which breeds in surface dung.

What would we do without them?

Moving dung around clearly gets it out of our way. Bringing it underground brings nutrients to plants, improves the soil structure and gets rid of parasites that could reinfect animals. The underground dung also increases the activity of underground microbes. Dung beetles are also an important foodstuff for bats. There is a concern that when wormers are used in cattle and horses, dung beetles can be killed by the chemical in the cowpat. And without dung beetles, we are all in deep shit.

Building healthy soil

• Don’t allow soil to be bare. When soil is bare, soil erosion takes place. If you have a gap somewhere, cover it with a green manure — basically throw seeds in to cover the soil. On farms, oats can be used to cover fields; in gardens, you can use comfrey or mustard. Use whatever you like, but don’t leave the soil naked!
• Try not to disturb the soil with digging or ploughing. Our local primary school came to visit once and calculated the amount of soil lost in a one-hectare field that I had recently ploughed. I can’t remember the exact weight, but it equated to the weight of 26 primary schoolchildren. They all rolled down the hill field to make the point. No-dig or light tilling is the way to go.
• Stop compacting the soil. When you walk or drive heavy machinery over the soil, it squashes everything beneath, and makes it harder for small creatures to wriggle through. So, make paths through your garden, and stick to them. And avoid using heavy machinery.
• Start a compost bin. Earthworms will love you for it. Just throw in your uncooked food waste, paper and cardboard, and forget about it. You may end up with lovely compost. Or, like mine, the stuff will vanish, magically disappearing into the ground, dragged away by earthworms.
• Stop concreting and hard surfacing. We are losing vast amounts of soil every year to hard surfacing, often for our cars. We need to find ways to allow soil to breathe. There are alternatives to paving your garden to park your car. You could go retro — in the 1970s, my neighbours all paved the areas along the wheel tracks of their cars. Grass was free to grow in between, underneath the car body. If you want it to look more stylish, you can use a lattice of concrete. This looks like a chess board, where there is a square of concrete, then one of grass, then one of concrete, and so on. Or you can use a geogrid mesh, which is strong enough to drive a car on, while sitting on your lawn. An additional advantage to all of this is that flooding is reduced when water can soak through the earth. And with the increase in rainfall due to climate change, we need our gardens to protect our homes.
• Only use animal wormers if you need them. Most vets will carry out analysis of dung, to let you know if your horse or donkey needs worming. Have this done before you routinely worm your animals. They may not need it.

• Make Your Home A Nature Reserve by Donna Mullen, published by The O’Brien Press. Priced €19.99, is out now