The robins and I have an understanding: any worm they can snatch they can keep. But they have to be quick off the branch, for I've grown adept at reburying any upturned earthworm with a quick flick of the spade and a murmur of encouragement. Readers with the habit of this column will know my high regard for Lumbricus terrestris and its mates.
L. terrestris, the common earthworm, does the heavy work in the garden and anywhere else plants flourish. Its deep burrows drain the soil and bring air to the recycling bacteria; it pulls down leaves from the surface, macerating and mixing them with earth in its gizzard and then casting them forth as the fine, crumbly particles that best suits the penetration of roots. The very process multiplies a thousandfold the bacteria beneficial to the soil.
Anywhere they're left alone - an old pasture, say - the earthworms in one hectare can pass about 90,000 kilos of soil through their guts in a year; in any apple orchard, they can, over the winter, remove 90 per cent of the fallen leaves. In my garden, their industry rewards me with the deep fragrance of fertility.
L. terrestris was the earthworm Darwin studied for his classic treatise, The Formation of Vegetable Mould through the Action of Worms with Observation on their Habits. "It may be doubted," he concluded, "whether there are many other animals which have played so important a part in the history of the world, as have these lowly organised creatures." This spring, my own interest in worms has turned to two less celebrated species, whose appointment with history seems nigh.
Lumbricus rubellus is small, squirmy and brighter red than most earthworms. Eisenia fetida is another smallish, brightly-banded curlicue: once the brandling of anglers, it is now the "tiger worm" of vermiculture. They are consumers of soggy leaves, cow-pats and old-fashioned farm manure, and both, I was delighted to find, were entwined in some hundreds in the bottom layer of my compost heap.
For a few years, the gospel of the "wormery" has been gaining ground among organic gardeners and smallholders, not to mention the subsidised householder composting schemes of more adventurous county councils.
Instead of drawing clouds of seagulls to noisome, methane-generating landfills, more and more kitchen waste now ends up in purpose-made bins, where teeming and well-cared-for worms convert it, over a few months, into a friable, soil-feeding compost and liquid manure.
Keen to see how much better and faster the process works than my traditional, untidy layerings of banana skins and weeds, I have followed many in adapting a redundant wheelie-bin with the requisite depths of drainage gravel and leafy layer (you can use torn paper) as a basic hideaway for the worms. Regularly fed from the sink-bucket, my couple of hundred pioneers should double themselves in 60 days or so and return some useful shovelfuls of compost by the autumn.
There is, as you might expect, quite an industry to all this now, even to the sale of specially designed, lockable wormeries with inhabitants "you don't have to touch" or even look at (try Grow Green Products in Blessington, Co Wicklow), and offers of unlimited tiger worms at so much per 500 (search for "tiger worms" on the Internet).
At www.irishearthworm.com, the Irish Earthworm Company urges wormeries not only for the sink-bucket but for a new type of septic tank. And this takes me on to Australia, where one of the most momentous projects in vermiculture is using millions of red and tiger worms, identical to those in my compost heap, to process raw sewage sludge from Brisbane in Queensland.
It's not a new idea, but this does seem to be the first large-scale application that has brought together all the necessary skills: entomology, microbiology, agronomy, chemical engineering and mechanical and civil engineering. At its plant in the Redlands Shire, 30km south of the city, the Vermitech company (www.vermitech.com) has processed more than 60,000 tonnes of "biosolids" - not only sewage sludge but pig slurry - into a marketable, deodorised manure safe to use on crops.
In traditional sludge composting, pathogens such as salmonella had to be removed by the heat of decomposition - a slow and expensive process. Only then could the material be fed to worms to produce garden compost.
The Redlands system has shortened the operation by feeding the worms a mixture of untreated sludge and shredded paper in steel cages 70 metres long, a metre wide and a metre deep. Over a 40-day cycle, a thin daily layer of sludge is added on the surface and the same amount of worm-casts removed from the bottom to be screened and dried. The success of the plant has led to a five-year trial for Sydney, in which more than 40 million worms will eat their way through 10,000 tonnes of biosolids a year.
It sounds a fairly robust proposition - all the more virtuous, perhaps, for being simple and organic. But while the basic process belongs to nature, it takes a fine-tuned technology to keep that number of worms alive and happy and functioning round the clock, and for the balance of microbes in the vermicast to come down on the side of public health.
THE Vermitech system (offered globally under licence) promises, at last, a way of returning human waste to the soil and its food chain, rather than letting it pollute rivers, lakes and seas. It exemplifies the kind of project I had hoped to find somewhere in the priorities of Ireland's new investment in science and technology.
After decades of official scepticism, the landfill crisis has brought an Irish reality to waste recycling almost unthinkable even one general election ago. But industry continues to use natural resources to make materials and products that are foreign to nature and beyond economic recycling, while generating toxic wastes in the process.
Nature, on the other hand, transforms old resources into new ones in a cyclic ecosystem. On a small and fragile island, no less than on the planet, this has to be our ultimate model for "sustainable development".
- Michael Viney welcomes observations for Eye on Nature sent to him at Thallabawn, Carrowniskey PO, Westport, Co Mayo. E-mail: viney@anu.ie. Observations sent by e-mail should be accompanied by a postal address.