Re-thinking the ragwort threat

Good for wildlife, I thought. Ragwort is a major nectar plant for insects including many butterflies, and the plant on which several important moths lay their eggs.

Visiting a nature reserve I noted someone had uprooted just about every ragwort plant along half a mile of trackside leaving it to die there.

It was an example of the mistaken actions people sometimes take when they wrongly perceive a danger.

“Ragwort is poisonous so we must get rid of it” must have been someone’s reasoning.

But pulling up a ragwort plant and leaving it by the trackside simply creates a another problem rather than curing one.

The danger for animals is in the shrivelled up dead plant, especially in hay.

Horses in particular will rarely touch live ragwort, probably because it doesn’t taste nice, and the bite they learn from is unlikely to have any serious effect.

In fact, studies suggest they need to ingest five percent to 25 per cent of their body weight to cause death. That’s quite a lot.

It is often overlooked that there are six species of ragwort.

Only one of them is referred to in the Weeds Act of 1959, namely our native “common” ragwort, Senecio jacobaea.

But they all look very similar. You need to be quite an expert to tell the difference.

The sad thing is that people who declare unthinking war against ragwort could be unwittingly destroying rare plants like the hoary ragwort.

There is also a lot of misunderstanding about Oxford ragwort which is usually found on brownfield sites such as disused industrial areas and railway sidings and is unlikely to cause any problems to animals.

I have spoken to various vets about the frequency of deaths amongst horses and cattle as a result of eating ragwort.

‘Quite rare’, is the invariable answer. But the problem is that no-one really knows. The symptoms are the same as for any other liver ailment, and post-mortems to get to the bottom of it are rarely carried out.

So ragwort gets the blame for all, even though it may be responsible for none.

Few people realise that the poisons found in ragwort are also found in other common wild plants which might even be more to blame than ragwort itself.

A much publicised figure of 6,500 horse deaths per year appears to be based on a tiny sample of ‘suspected’ but unproven cases, subjected to questionable calculations to scale them up to a national figure.

A more scientifically based Defra report indicates only 10 proven animal deaths between 2005 and 2010.

This result matches similar official surveys in France and the Netherlands. There may be a problem, but it appears to be very small.

The 1959 Weeds Act does not require landowners to report or pull up ragwort wherever it occurs on their land.

It simply provides the Government with a means of stepping in if and where a serious problem arises.

Only then, when faced with a Government order, must a landowner take action.

Equally, the Ragwort Control Act 2003 places no obligations on landowners.

It was introduced to enable the Government to produce a Code of Practice for the control of ragwort. This is guidance, not law.

It suggests that it is wise to remove any ragwort growing in or within 50/100m of a field used for grazing horses or cattle, or for hay production.

These distances are based on scientific studies which indicate most seed drops close to its source plant.

Some 30 different insects depend directly on common ragwort.

These include the beautiful cinnabar moth with its black and yellow caterpillars which actually extract some of the poison from the plant to make themselves unpalatable to other predators.

Sadly, there are local authorities and even wildlife trusts which have publicised incorrect information about ragwort leading to its unnecessary destruction to the detriment of our biodiversity.

If vast numbers of horses are really dying from ragwort poisoning every year, then common sense suggests the fault must lie with the management of paddocks and hayfields, not with the presence of ragwort in the wider countryside.

Howard Frost writes on behalf of Butterfly Conservation Yorkshire and can be contacted via www.yorkshirebutterflies.org.uk where you can also find the latest news on Yorkshire’s butterflies and moths.