Types of Worms
By Steph Boxall
A common misconception is that a worm is a worm is a worm. There are actually over 20 native earthworm species in the UK and they can be sorted into three main groups depending on their feeding habits and where they live. All are responsible for soil creation, aeration and adding nutrients and organic matter into the soil
The Different Types Of Worms
Firstly there are the ‘epigeic’ worms that live on the surface of the soil, rarely burrowing at all. They live in their preferred food source – leaf litter, dung, rotting wood, compost heaps. Eating and living in the organic matter and producing fine, highly nutritious casts known as vermicast. Tiger worms (eisenia fetida) are one such species of epigeic (surface dwelling) worm and are the most common worms to be found in compost heaps and used in worm composting bins (they are Worm Soils’ worm of choice). Small in comparison to some earthworms, they are pink and, as their name suggests, stripy. The European Nightcrawler (dendrobaena veneta) is another example. Larger and more grey in colour than the tiger worms, they can also be found in compost heaps and are most often used in the fishing bait industry.
Secondly, the ‘endogeic’ worms. They live within the soil, burrowing horizontally through the earth and rarely coming to the surface. They feed on the soil they burrow through and are larger than their composting cousins. There are many different species of endogeic worms and all are pale in colour – pale pink, grey, green or blue. Their burrowing activity is very important for soil structure, allowing spaces for air and for water retention, however compaction of the soil can restrict their movements.
Thirdly and finally, the ‘anecic’ worms. The deep dweller, the long burrowers. Making permanent vertical burrows through the soil which can be up to six feet deep, these worms feed on leaves lying on the soil surface by dragging them down into their burrows. They leave their worm casts on the surface of the soil, sometimes in heaps around the burrow’s entrance. It is these worms that leave the worm cast piles on lawns which will be familiar to many people. Size-wise they are the largest of the earthworm species (in the UK) and are dark red or brown with slightly paler tails. By dragging their food down into the soil, they are responsible for adding crucial organic matter to the soil, as well as allowing air to infiltrate deep below the surface, crucial for healthy soils.
The Importance Of Each Worm For Our Soils
Together, the three types of worms work together to create healthy, living, breathing soils full of nutrients, microbes, air and worms. They are a vitally important part of a working ecosystem. Unfortunately, human activity can disrupt all or parts of the process – Compaction with heavy machinery or over grazing, artificial pesticides and fertilizers, excessive ploughing. These factors damage the worms themselves or make the soil uninhabitable and an imbalance or complete destruction of the soil ecosystem results in poor, stagnant soils devoid of life.
However, soils can be repaired, negative human impacts can be reversed. Nature has given us the tools to do so. Worms of all types and species, along with their worm casts (vermicast) are the answer to poor soil quality. Look after our worms and they will look after our soils.
