By Annika Rice
Earthworms are probably one of the most underrated animals on this planet, and yet one of the most important.
People must have been aware, probably since the dawn of agriculture, of the beneficial effects of earthworms on the soil, but Charles Darwin was the first to study the activity of earthworms in a systematic way and to observe in detail the conversion of dead plant material by worms into soil organic matter (1).
In the UK there are 27 species of worms (2) that utilise different habitats and food preferences. Some species live on the surface of the soil and amongst the leaf litter, others live in burrows under the ground and some prefer a good compost heap! Some species will be a common sight in your garden, while others prefer woodland habitats.
Whatever their lifestyle choices and habits are, earthworms do a vital job. Often known as ‘ecosystem engineers’, or as Charles Darwin called them ‘nature’s plough’s’, the humble worm engineers the soil to allow ecosystems to thrive all over the world (1).
Firstly, the burrows used by many species allow air and water to penetrate into the soil. One species lives in a single vertical burrow of up to 3m deep. Their movement through the soil also helps to mix organic matter into the various layers of soil (2).
Secondly, Earthworms feed on dead, decaying organic matter ranging from leaf litter in a woodland to your vegetable scraps in your garden compost heap. They decompose this organic matter and release nutrients back into the soil for living plants to use.
Thirdly, the worms will often drag dead organic matter into their burrows underground. They will break the organic matter into smaller pieces which will then be broken down further by bacteria and fungi in the soil. The presence of worms increases the bacteria and fungi in the soil, which increases the amount of nutrients being released into the soil. (2)
So worms are triply important to farming – as well as aerating the soil and incorporating dead plant material into the soil organic matter, they also help to maintain or improve soil structure that supports plant and crop growth. Across all our farms at Countryside Restoration Trust we do everything we can to support healthy earthworm populations including ‘reduced tillage’, which means we try to leave the soil as undisturbed as possible. There’s lots we can do and we hope that you will join us in helping to look after the humble earthworm.
- Darwin, C. 1881. The Formation of Vegetable Mould through the Action of Worms with Observations in their Habits. Murray, London.
To promote #MuddyUpBritain over the next few weeks and in the lead up to International Mud Day on 29th June 2017, the CRT will be publishing a series of blog articles to inform and inspire you. If you’re stuck for something to do there will also be various school and family events led by our education team, so please follow us on Twitter and Facebook for all the latest news.