I HAVE been told that when I was four or five years old I was pushing a toy pram around when a neighbour asked to see my doll. Apparently she was surprised to find half a dozen earthworms instead. I think this is true because I have a very vague ‘snapshot’ memory of the incident, and I never had a doll. (I was not deprived, I just didn’t want one.)
Worms always seem to be regarded as a bit of a joke but they are wonderful creatures and we could not do without them. There are 27 species in the UK, and more than 3,000 throughout the world. They are basically a long digestive tube with a muscular cover. The mouth is at the head and the other end produces what you would expect, which adds to the fertility of the soil. Some types burrow and others live on the surface, but between them they digest decaying organic material and slowly churn the soil, mixing the layers and aerating it, which benefits plants and allows rain to drain through it rather than running off the surface, in a process known as ‘bioturbation’. Charles Darwin called them ‘nature’s ploughs’.
The most familiar is Lumbricus terrestris, or lob worm.
It digs vertical burrows as deep as 6ft and pulls in material from the surface to decay to the point at which it becomes tasty. This is the worm that leaves casts.
Other types burrow horizontally, and compost worms (of which there are several species) live exclusively in rotting vegetation.
Here is a fascinating film condensing a month’s earthworm activity into a couple of minutes.
Here is another showing compost worms in action.
When we moved to Lancashire a few years ago we made a small garden from scratch. That meant buying in topsoil, which arrived sterilised and dead-looking, so I needed to get some worms. I found there are plenty of firms selling them on the internet, currently around £20 for 100 (I wonder if I missed my way in life?) The worms arrived safe and well in a small box by post, and as I was distributing them on the surface it started to rain, which was perfect. I am pleased to say the little fellows have thrived and have worked very hard for me. The 100 I bought must now be in the thousands. Another batch have made me a beautiful, sweet-smelling compost heap.
This is the interesting site of the Earthworm Society of Great Britain.
PS: We planted some Gunnera manicata (sometimes called giant rhubarb, though not closely related) at the side of our stream and they have grown well. They die down completely in the winter and are just starting to sprout new leaves. I thought I would take pictures every so often so that you can share their dramatic growth. This is No 1, showing the site.
And this is a close-up of the plants with one leaf showing and others breaking through. The brown strips are last year’s stems and leaves.