ANOTHER LIFE/Michael Viney: Horseradish sauce, that white, creamy relish of ineffable, nose-tingling pungency, is a taste I acquired in an English childhood - years spiced also with pickled onions and a throat-scarring confection of mustard-soaked vegetables known as Piccallilli.
Horseradish sauce came in the smallest jar, as befits such a precious condiment, with no hint that it came from a root you could easily grow in your garden. Almost too easily, indeed, since Armoracia rusticana, once established, could be with you for ever.
My horse-radish patch, planted from a handful of root-cuttings, is a thicket of sword-shaped leaves, now dying down for winter. I should start a new patch, to keep up the flavour, but any fragments of root I leave behind will burgeon into a whole new thicket. Armoracia rusticana is a plant that looks after its future.
Botanists call it an "archaeophyte" - a plant of ancient introduction that spread to become a naturalised species. (Archaeophytes were those brought into these islands before 1500 - those that arrived afterwards are "neophytes").
Armoracia, with still-mysterious origins in eastern Europe, was widely used as a medicinal herb by the Middle Ages, but its success as a relish took it to North America and beyond.
Despite setting no seed, horseradish has spread throughout England and the lowland parts of Wales. In Scotland, it follows the lowland axis from Glasgow to Edinburgh. In Ireland, it grows most densely around the cities (but not Limerick, for some reason) and at many coastal locations; it is even on the Aran islands.
I can tell this from one of the maps in the massive, 910-page New Atlas of the British and Irish Flora which weighs in at almost 5 kilos and will cost you £99.50 - plus postage - from the Oxford University Press, e-mail: book.orders@oup.co.uk (not available in book shops). Inside the back cover comes an interactive CD that, given enough megabytes, lets you make and print your own maps of different regions.
Robert Lloyd Praeger (The Way That I Went) would have been gobsmacked. The plants he found on his 5,000 miles of tramping round Ireland helped to create the first thorough record of the island's wildflowers and ferns, the Irish Topographical Botany of 1901. It took another half a century to produce the first Atlas of the British Flora in 1962, which included Ireland's records, and as long again to come to this momentous tome, which at least remembers to put Ireland in the title.
For all the personal vigour of our botanists, and the census catalogue of Irish plants, published by the National Botanic Gardens, much of the recording of what grows wild on this island, and where, has fallen to the Botanical Society of the British Isles (BSBI) working through an Irish membership of voluntary fieldworkers.
It was the BSBI, together with the UK Biological Records Centre at Monks Wood, that undertook the new atlas (funded mainly by DEFRA, Britain's environment ministry). Its field volunteers collected most of the nine million records from almost every 10 km square in these islands. In the Republic, Dúchas added its own recent records of scarce plant species and it also helped fund the CD that will mean so much to its conservation work. When the atlas is given its Irish launch at the National Botanic Gardens next month, Dúchas plans to express its proper appreciation to the BSBI.
The atlas (edited by Chris Preston, David Pearman, Trevor Dines, all British) maps the change in range and frequency of almost 3,000 flowering plants and ferns. Only 1,400 of these are native in the UK - even fewer in Ireland - but all kinds of introduced garden plants have escaped to the wild. Garden escapes have certainly helped to make Belfast, with its 555 species, one of the hot-spots of diversity in these islands.
The ebb and flow of species has been heavily influenced by changes in land use and farming methods over the past 50 years. Archaeophyte "weeds" such as cornflowers have been virtually wiped out in cereal areas, and the disappearance of small arable fields in western Ireland and Scotland has meant the decline of many more. The loss of ancient meadows and old permanent grassland, and the spread of overgrazing and conifer forestry in the uplands, have all taken their toll on wild plant communities, and the artificial enrichment of land and water from fertilisers is hitting the range of plants adapted to poor soils.
What the survey data means to the Republic of Ireland will take time to tease out, so it is a relief to seize upon any small reassurance. The insectivorous large-flowered butterwort of Kerry and Cork, for example, one of Ireland's loveliest flowers, is still safe in its boggy range and even "locally abundant".
The atlas and CD are an obvious must for botanists and ecologists, but how much of a Christmas extravagance would they be for anyone else? There are no pictures or descriptions of plants - you get those in a field guide. But this is a book for long-term browsing, full of glimpses into the shifting kingdom of our wild plant families.
It's also a work still in progress. On the mistletoe map, for example there are a few up-to-date records in Ulster and only an old one for Dublin, but nothing further south. This misses the mistletoe described to me a few years ago as growing "in two hazy spheres, each two feet across" in the topmost twigs of an old apple orchard in County Waterford. Will it still be there for Christmas, next time round?