Neil Jones wrote:
[...]
Here we go again. I have posted several times about this but it needs doing
again I see,

No actually it isn't s poison that is stored in the liver. The damage is
cumulative but the poison disappears. There is actually very very little
risk from ragwort at all. It can cause poisoning in very very rare cases
but that is usually caused by it being present in hay.

There are a whole series of thresholds before any damage is done at all so,
contrary to what you may have read, small doses have no effect at all.

I know that there is a lot of stuff around telling you that Ragwort is
dangerous but it all comes from a few dodgy sources who have been
publicising it for their own interests. It is almost a classic example of
how to deceive people with bad science. Since I got interested in this I
have spent a lot of time checking scientific papers to get at the truth.

Some of the bad science has even got repeated in government press releases!

For more details on the science see http://www.ragwortfacts.com/

There is little risk to animals like rabbits and Guinea pigs for unless it
is dried it tastes and smells so awful to them that they won't touch it.

In fact one of the signs that a place is being overgrazed, by rabbits or
anything else, is that ragwort its growing there in abundance.

The moth is gorgeous and the website debunks a myth about that too, but it
isn't the only thing that depends on this plant.


As a sometimes enthusiastic revisionist about many things, I agree it's
an interesting site; but it doesn't seem to quote very many papers, and
it certainly doesn't deny the toxicity of these plants. You don't want
them in hay or silage. I wasn't at all cheered by reading that some
unnamed scientific hooligans only managed to kill 75% of a sample of
cattle by feeding them 0.6% of their body weight of fresh ragwort a day
for 20 days: in the dried form, that would be quite a small amount --
perhaps something like the volume of a packet or two of tea -- and
might well escape the stockman's detection. The way the result was
quoted represented the dose as very large, and appeared to be an
attempt at reassurance.

I was struck by the quoted findings of a US study on the seed dispersal
of one species (it didn't say, but I assume it was only a single
species). It seemed the results of the study were being called in
evidence to suggest that there was no need to worry much about ragwort
populations on waste ground catastrophically "infecting" cultivated
areas: my intuitive sense is that that's right, as long as neighbouring
areas are well managed.

Of course people shouldn't panic about the ragworts; but they _are_
toxic, and they aren't endangered, so getting them out is generally a
good idea, especially in fodder crops. Even if one has no susceptible
stock, I think it's reasonable to be a good neighbour to others,
especially if any of one's neighbours are practising organic husbandry
-- they should be helped, not given extra work.

--
Mike.