Madam, - Rehabilitating the good name of ragwort is probably a futile exercise due to the national neurosis surrounding it. In your Editorial of August 21st and in readers' letters it is lumped in with invasive foreign thugs such as giant hogweed and Japanese knotweed. However, I think that someone needs jump to the defence of a true native of these islands.
1. Ragwort is not, as you stated, "highly poisonous" - certainly not to humans, and animals have to eat considerable amounts to be poisoned by the alkaloids that make it toxic. Indeed, sheep are known to eat small quantities without any harm. While large quantities of ragwort can be fatal to cows and horses, neither animal is naturally inclined to eat it, as it has a very bitter taste. In fact, both animals will tend to avoid the plant unless it is dried out or where other sources of food are not available.
In one study (Ford, EJH 1973: Clinical aspects of ragwort poisoning in horses. Vet. Annual 14, 86-88), a horse consumed a quarter of its own body weight in ragwort and survived!
2. While in Ireland the plant has been subject to stringent legislation since 1936, we remain the only country where ragwort is native to adopt such draconian measures. UK regulations are more relaxed - a landowner can be required to control the spread of the plant, but its growth is not illegal and landowners are under no statutory obligation to control its growth. A UK study (State-Veterinary-Journal. 1991, 1: 4, 16), found that the number of reported incidents of ragwort poisoning in cattle in Britain were 26 (1985), 10 (1986), 16 (1987), 13 (1988), 7 (1989), and 10 (1990). While the British Horse Society has bandied about some larger numbers for horse deaths, their sampling approach (to put it kindly) lacked any scientific basis.
So before the resources of our police and county councils are taken up battling fruitlessly against one of our own, perhaps those same resources could be better directed at wiping out those recent invasive blow-ins. In particular, county councils need to look carefully at their hedge-trimming activities. Japanese knotweed reproduces primarily by vegetative regeneration of rhizomes and fresh stems, so the annual cutting of hedges where knotweed exists is actually assisting the spread of the plant throughout the country. - Yours, etc,
COLIN COOPER, Derrymeeleen, Ballineen, Co Cork.