The catcher in the rye

The ragwort season is coming to an end - and not a day too soon. The poisonous weed, with its bright yellow flowers, has spread more widely than ever this summer, in spite of determined campaigns to eradicate it, and horse owners in particular fear that it is now out of control.

Ragwort is a tremendous survivor and incredibly prolific. A single plant is capable of producing between 130,000 and 150,000 seeds, of which 70 per cent may germinate in the following year. Thus every plant can reproduce itself 100,000 times and seeds lying in the earth can remain viable for at least 10 years. Being light and fluffy, like those of dandelions, seeds travel huge distances, especially along transport corridors such as motorways and railway lines. Some are towed along in the air by the suction of passing vehicles, while in wet weather thousands stick to the coachwork of cars or trains, so that they are carried for miles before falling off to found fresh colonies.

The most sinister feature of ragwort is that it acts on grazing animals so slowly. A large amount - two or three pounds - eaten quickly can kill a horse within days; but small amounts ingested over a period of time produce no visible symptoms until the alkaloid toxins in the plant have done irreversible damage to the animal's liver. The process may take months or even years, but in the end the horse starts to lose weight, its coat falls out, it gradually goes blind, suffers terrible abdominal pains and eventually collapses and dies. There is no record of how many have succumbed in this way: a few cases have been reported, but experts believe most owners who lose an animal are ashamed to admit that they have been careless enough to allow it access to poison.

The traditional way of clearing ragwort from a field was to put sheep in and let them eat the plants off - for farmers believed sheep were immune to the toxin. Now research has shown that they can be as badly affected as any other ruminant. In any case, although grazing may suppress the weeds for a year, it does not kill them. The only way is to spray them repeatedly with weedkiller - which is very expensive, and destructive of other plants - or to eradicate them by a combination of digging, pulling and burning.

Horses and cattle generally leave the plant alone when it is growing, for its harsh, bitter scent proclaims its toxicity; but when cut and wilting it becomes more palatable - and many horse-owners are now alarmed that dried ragwort may have found its way into their bales of hay. Dried leaves lose their distinctive dark green colour, turning a harmless-looking brown - but still the tell-tale red stalks should give warning.

In the view of Nichola Gregory, the quick-firing press officer of the British Horse Society, "the problem seems to be doubling every summer. Last year it was appalling, but this year it's been everywhere. Hundreds of people have been out clearing the stuff, but the situation will get worse: we may not see the real damage that's been done for three or four years."

It was the BHS which first raised the alarm four years ago and galvanised big organisations like the Highways Agency, Railtrack and local councils to tackle the seas of ragwort growing on road verges, railway embankments and waste ground. This year, in July and August, the Highways Agency had teams out all over the country, pulling the weed by hand: in Devon and Cornwall alone pounds 150,000 was spent on the task.

Now, says Ms Gregory, the greatest danger is that the plants have established themselves widely on private land, and many owners are taking no notice. Because ragwort is classed as an injurious weed under the 1959 Act, it is an offence to let it spread and anyone who gives it growing space can in theory be prosecuted. In practice, however, neighbours do not like taking each other to court - especially as, for a case to succeed, the complainant would have to prove that he or she had suffered financial loss.

In August the BHS launched a National Ragwort Week, and for months the organisation has been vainly urging the Ministry of Agriculture, Fisheries and Food to take action. The official line emanating from London is that MAFF can act only when something directly affects agricultural production and that the Ministry has no resources to deal with ragwort. This Ms Gregory dismisses as "absolute nonsense". In mid-July she wrote to Baroness Hayman, the Agriculture Minister, suggesting the issue of a standard letter and leaflet on how to deal with the weed - and she is still waiting for a reply.

The extent to which ordinary people are worried was shown by the response to the Let's Rout Ragwort campaign launched by the Country Landowners' Association in April. A leaflet produced by the CLA was in such demand - not only from members, but from the police and local councils - that the first 100,000 copies were taken up in record time and a reprint had to be ordered. One of the CLA's recommendations was that people pulling or digging up the plants should wear protective clothing, because contact with juice from leaves and stalks has been known to cause headaches and allergic rashes.

With agriculture in a parlous state and rumours proliferating that large areas of the countryside will soon turn to desert because no one can afford to farm them, it is all too easy to imagine a nightmare scenario in which weeds like ragwort finally run riot. After only one season of neglect, a set-aside field looks horrible, bristling with a ragged array of docks, thistles, fat hen, nettles and other plants useless to the human race.

What will the country look like in 10 years' time if thousands of acres of land are abandoned and pernicious weeds have taken over because our urban government has neither the will nor the money to root them out?