I could almost certainly offer a generous cash reward to anyone who can find three of these in my garden and be very confident that I would not have to pay up.
In fact, I could probably offer a significant cash prize to anyone who can find just one of these in my garden in, say, a one-hour search without much risk of having to open my wallet. ‘These’ are earthworms, common … if seldom seen … inhabitants of most fields, parks and gardens as well as moors, woodlands, hillsides and scrubland. But they are as rare as hens’ teeth in my garden; and my garden is the poorer for their absence, for earthworms are an essential part of productive soil.
It’s easy to spot the scarcity of earthworms in my garden. The autumn leaves which fell to the ground are still lying wherever they have been deposited by the wind. They haven’t been seized by worms and dragged below the surface of the soil to be eaten or to plug their underground homes. Earthworms eat decaying vegetation and to help with its digestive system, the worms also ingest fine particles of sand and grit which they find in the soil, using this to grind the vegetable matter into a fine paste in their intestines as part of their digestive process. The post-digestive material is ejected in the form of worm casts which, of course, are also missing from my garden. And when one reads that investigations in the United States have show that fresh earthworm casts are five times richer in available nitrogen, seven times richer in available phosphates, and eleven times richer in available potassium than the surrounding soil, one realises what my soil is missing out on. Nitrogen is largely responsible for the growth of leaves on plants; phosphorus is responsible for root growth and for flower and fruit development; and potassium helps plants make strong stems and keep growing fast.
I must add artificial fertiliser to my soil to replace these elements which my plants need to grow and flourish, elements which worms would supply free – were they present. I must also clear away plant detritus which worms would eat – were they present. And I miss out on the other benefits which these gardeners’ friends confer on farmers, other gardeners and, indeed, on all plant life. The worms’ nocturnal surfacing to find food necessitates their equivalent of human mine shafts, vertical passages between the surface and the underground world where they spend most of their time. These shafts let water drain into the soil easily when the weather is wet and allow air into the top layers of the soil when the weather is dry. Both of these characteristics benefit the soil and encourage plant growth, principally by allowing plants’ roots access to water and to oxygen. And both of these processes are further assisted by the underground horizontal tunnels made and used by the worms.
I don’t care for worms, although I know that it’s not their fault that they feel slimy to the human touch, for they must stay moist to allow their system of ingesting air and fluids through their skins to work. If they dry out, they die; and this simple fact explains why they are nocturnal feeders … seeking to avoid any possibility of being exposed to the sun’s rays … and why they are not found in arid deserts. And although they feel slimy, their bodies are actually quite hairy, the tiny, well-nigh invisible hairs being essential to their ability to move about in the soil. They mate to produce fertile eggs, each member of a pair taking it in turn to act the part of the male and the part of the female. They have a remarkable ability to recreate much of their body, that part of a severed worm which has the head being capable of such regeneration. And, although they have no eyes and cannot see light, they have specialized nerves which end in photoreceptor cells in their skins and can sense brightness. But for all these attributes, I still don’t like them – yet I do wish they’d come to live in my garden!