Defra Ragwort Code of Practice Nonsense

Defra's ragwort Code of Practice is widely quoted and cited, but it is really often quite an unscientific document.
Today I am celebrating a little as this blog has been running for several years now and every August it gets the highest number of hits as ragwort hysteria is at its height and every August it does better than the one before. This year however it broke the record for the highest number of hits in a month some weeks ago and yesterday it passed the point of double the hits of last August. So today I thought it would be appropriate to tell everyone just how incompetent Defra have been. They have been very incompetent.

First let's look at one of the methods they use to estimate the risk to horses . To quote them:-

A figure of 500 horse deaths from ragwort poisoning in 2000. This figure is based on the number of confirmed horse deaths from ragwort poisoning seen by the Philip Leverhulme Large Animal Hospital Teaching Hospital at Liverpool University as a percentage of all the horse cases treated during the year, and grossed up to be representative of the total horse population.

I can hear the gasps from those of you with training in statistics! They did what!!?

You can't do this and get a sensible answer. Cases in a hospital,. whether of people or of animals, are not a representative sample of what is the case for the country as a whole. They are all concentrated in one place, so you cannot extrapolate and get a meaningful answer. Imagine, if you like, an opinion poll on political beliefs asked just people  in one of the party headquarters and then  extrapolated to the whole country. Do you think it would give a proper accurate answer?

Dr Ben Goldacre (a medical doctor and journalist) is well known for his work on educating people about Bad Science , both through his book of that name and his similarly named column in the Guardian  newspaper. In one of his articles he makes a very relevant comment which seems entirely pertinent to this situation.

We can't do a full census of the whole population every time we want some data, because they're too expensive and time-consuming. Instead, we take what we hope is a representative sample.
This can fail in two interesting ways. Firstly, a sample can be systematically unrepresentative: if you want to know about the health of the population as a whole, but you survey people in a GP's waiting room, then you're an idiot.

You can actually do a GCSE in statistics. ( For foreigners this is the General Certificate in Secondary Education that school pupils usually do at 16.)
These are the assessment objectives:-

AO1 Analyse a statistical problem and plan an appropriate strategy
AO2 Describe and use appropriate methods to select and collect data
AO3 Process, analyse and present data appropriately
AO4 Use statistical evidence to identify inferences, make deductions and draw conclusions

Ask yourself, do you think Defra would pass?

What is more while we don't actually know how many cases of ragwort poisoning the Phillip Leverhume Hospital recorded in 2004 when the Code of Practice was published., thanks to the Freedom of Information Act I can tell you how many they recorded in 2006. In fact I have their figures for 2006-2010, a full five years. They didn't record a single case in the whole five year period! 

It is also worth noting that the tests used would not have been definitive anyway since no test for ragwort poisoning that is definitive exists. The changes in the liver cannot be distinguished from other causes such as those caused by toxins produced in mouldy feedstuffs. See Ragwort Poisoning test.

Then we have Defra distances for where ragwort should be controlled in the vicinity of grazing land. They bear no resemblance to the studies on seed dispersal. We are told there is a risk at 100m when the seeds have been shown not to normally travel more than about 37 metres. Taken with the bizarre overestimation of poisoning risk this is totally unreasonable.

The whole idea that fresh ragwort is a  significant danger to livestock is completely without foundation and contrary to one of the most basic tenets of biology. As I keep saying, animals have co-evolved with the plants with the ragwort toxins which are actually 3% of the plants in the world. Those that ate poison died and did not pass on their genes. We find when we look at the research that animals have a whole set of resistance systems one of which is a complex system of taste genes and receptors which means they know what is good to eat.

This of course makes complete sense. The man who discovered this is so venerated in the UK that if you were to stop the average person in the street you would find they were carrying his picture in their wallet.
Charles Darwin is featured on the Bank of England Ten Pound Note!

The only problem is when owners abuse their animals by feeding it  in quantities in hay or where animals are cruelly abused by starvation. Just remember here that when you throw out the nonsensical claims of poisoning figures derived by measures that would not apparently get you a pass grade in a GCSE exam, and you exclude the abuse cases, ragwort is not a problem at all. Poisoning even including the abuse is actually very rare.

Then of course there is the damage to the environment, as Buglife put it recently in discussing the New Forest
( Again for non-UK people an ancient royal hunting ground  that was "New" when it was created by the man who became king in 1066.)

Ragwort within dried hay is known to cause illness in horses and hay-growers have a duty to remove it from their hay crop. But horses and ponies will not eat it as a live plant within open heathland and pasture. Indeed, ragwort and New Forest ponies have co-existed happily for centuries with no recorded cases of ragwort poisoning.

Absolutely and their expert Steven Falk said

"Ragwort pulling in the New Forest is a truly ill-informed and damaging activity that is totally unnecessary. There are so many rare insects in the Forest, and it is well known that a general reduction in the number of flowers in the Forest over recent decades has placed many insects under severe threat of extinction there. Examine any patch of flowering ragwort in fine weather and you will see an astonishing array of bees, butterflies, hoverflies and beetles".

Finally we come to a spectacular example of poor  critical thinking skills in Defra's guidance

A particular concern amongst conservation groups is that the public pressure surrounding the Code will compel land managers to carry out more extensive control measures than they would otherwise...........

There are concerns that the risks presented by ragwort on grazed nature conservation grasslands could lead to major changes in grazing regimes. These could conceivably include the abandonment of grazing on grassland and heathland sites, leading to the development of scrub and woodland which may have a consequential significant effect on biodiversity.
22 However, as has already been stressed it is not the intention of the Code of Practice to affect the balance of biodiversity. It should be remembered that the control of ragwort has been required long before the introduction of the Weeds Act 1959, which consolidates earlier legislation dating from 1921, without resulting in such drastic consequences

It is really hard to find a calm form of words  to describe what at best is seriously cognitively deficient misinformation and in reality seems more like egregious dissembling.

It doesn't matter what the "intention" is, it is the effect. In fact it is agricultural intensification pushed by people like Defra that has led to the massive declines in wildlife in the UK. Furthermore they know that ragwort control, which is NOT  automatically required by the legislation as they try to imply, was never pushed before the current hysteria. It also sounds rather like an argument from tradition which should lose any students marks in a science essay as it is a well-known example of a logical fallacy

 I want to reuse this blog post  You frequently encounter people on-line who say things like Defra are experts what do they say , or you should listen to Defra they  are part of the government they must be right. This is an answer to the people who say that.

 This is another one of those logical fallacies it is called "argument from authority". It is a falsehood. Just because someone is in a position of authority doesn't mean they are right. In this case Defra have made a real hash of some of their science.

Indeed, we know from very good, basic and fundamental research into the nature of personality that those who argue from tradition and authority and who are concerned that people have a responsibility to follow government advice tend very clearly to be less intelligent and we do see such examples out in the world of the ragwort basher.


And really finally a little joke. There is a word in Welsh. It is spelled with two Fs but the sound is the same. "Deffra". It is a command. It means "Wake up!". I think they should!

Ragwort fungus nonsense

A really fantastic case of nonsense appeared recently in the Penarth Times.

A PENARTH resident has labelled the land near Sully Moors Road a “field of death” and raised concerns after several horses started grazing on the land.
The resident, who asked not to be named, has warned about the dangers of the horses escaping, from being poisoned by the fungus ragwort and the risk of them being stranded on higher ground if the land becomes flooded in the winter.

So ragwort is a fungus now is it? No it jolly well isn't. It is a flowering plant. This is another case of the totally inept quality of journalism that fuels the hysteria.

There is probably no risk from ragwort since we know very clearly from evolutionary biology that horses have evolved to avoid the fresh plant. So unless it is in hay or the animal is starving there is no problem but it doesn't stop the panic about the yellow peril fungus triffid :-)

Later on of course we find there is no cause for concern.

Christina Roberts-Kinsey, Principal Trading Standards Officer for the Vale Council, said: “Trading Standards take all complaints and reports of animal welfare seriously and investigate to the fullest extent. We are in receipt of a complaint regarding the welfare and identification of the current herd of horses grazing at Sully Moors Road.
“In response to the complaint a joint inspection was undertaken by an animal health officer and a specialist equine veterinary surgeon. This inspection identified there are currently no welfare issues with the horses. There is, however, a small amount of ragwort which has been addressed with the owner and a schedule of works is currently in place to remove the weed.”

There is an interesting comment on facebook where someone who clearly knows the field says that the yellow flowers were actually buttercups. Who knows? But it really wouldn't be the first time the two have been confused.

Mad Panic in Scottish Borders

Today's blog posting is about the silly unnecessary panic in the Scottish Borders as reported in the Southern Reporter

Councillor Gavin Logan is expected to raise the issue of the toxic plant in the open questions section of the meeting.
He is set to ask officials: “Has the council any long-term plans to deal with the scourge of ragwort on council-owned land?”
The Conservative councillor for Tweeddale East told us: “The point of the question is, if the council are not controlling ragwort, why should the other landowners in the Borders bother?”

Well perhaps the council should be sensible and not fall for the hysteria on ragwort.
Poisoning is so rare as not to be of any significance and most of the stuff is made up. The statistics seem to indicate that grass is a worse problem for horses

Under the 1959 Weeds Act, landowners, including councils, are bound to remove the noxious weed from land they own.

 This is not true the weeds act does not say that. There is no automatic responisbility placed on landowners or councils to do anything. See this briefing on ragwort law

He admitted: “There are cost implications, however potential costs can only rise if ragwort continues to spread.”

To right this is a waste of money. Ragwort is not increasing. Ther last government survey showed a really significant decrease . There is a recognised psychological phenomenon where somehting seems commoner because it is drawn to someone's attention.

When complaints have been made about the propaganda the Advertising Standards Authority has stopped adverts..


Ragwort is one of the most important wildflowers  for biodiversity the charity Buglife has a special set of pages.


A large set of myths about ragwort are debunked here

Ragwort He Who Burns His Buttocks Must Sit On The Blisters

A piece appeared in the Daily Telegraph recently. It appeared only in the print edition it would seem since
I cannot find it on-line.

Professor Derek Knottenbelt a well known figure in the ragwort debate has been complaining that people don't like what he says.

There is quite a bit of research into scientific type people and it seems fairly clear that they get irritated by nonsense. You will find debunkers all over the net debunking nonsensical claims and I am afraid that the same appears true for many of  the professors claims. There are, it seems, rational people who debunk him.

Derek Knottenbelt , professor of equine medicine at the University
 of Liverpool, has spoken out about the lethal effect the plant can have if the
 animals are exposed to it over a period of time, and has advocated measures to
 control its spread.

But since he began raising his concerns over what he calls
 a "silent killer", he has received a torrent of angry letters and emails,
 and even anonymous phone calls, from opponents claiming to be concerned
about the environment. 

He has done a little bit more than argue for control measures. He has argued, it seems,for the total elimination of a native wildflower. Now of course it would be wrong to harass someone, but he has been making some pretty strong statements that are not, it seems, supported by the evidence.
For example, claiming that ragwort is a severe problem in South Africa when the experts there say that there is no evidence that it grows there!

The article continues

 A solution to the problem is necessary, he said, but with such bitter opposition
 to ragwort control, the debate has become polarised.
 "I just can't get my mind around why people are so defensive around
it on the one hand, and so irrational on the other," he said.

This really does seem to be the pot calling the kettle black. Professor Knottenbelt is quoted in a number of places saying "It is toxic to humans, so what the hell are we doing with it in this country"
To someone with a detailed knowledge of botany this seems highly irrational indeed. There are many many poisonous plants in Britain. Even oak trees contain toxins. Potatoes and tomatoes grow on plants that have poisonous parts. Bluebells and daffodils are poisonous too. If we were to eliminate anything possibly toxic we would wreck our environment. 

An earlier wave of malicious letters had arrived after he warned several
 years ago that around 500 horses and ponies were struck down with ragwort
 poisoning annually, he said.

"I got hate mail saying 'this is rubbish and we're going to lose more of our
 summer beauty', that it's not called summer gold for nothing, and so on,"
he said. He has nevertheless continued to speak out about what he fears is a
"ticking time bomb" for horses.

It is entirely possible that he may have had mail criticising him over his claim of 500 horses dying a year, because he has apparently published the method by which he makes this claim in a newspaper and it appears entirely based on a nonsensical use of statistics. This is coupled with the fact that a Freedom of Information Act request to his university showed that , despite his saying that he gets more than ten cases a year, that they had recorded not one single case  in a five year period.

This link goes to a page giving a list of questionable claims by the professor 
These are examples through the years, such as saying  that ragwort is increasing ,when a government survey said it decreased.; that the number of horse deaths would double because of this; that ragwort could cause problems  with the meat , when the experts and a standard textbook say not; that the cinnabar moth ( which isn't the main issue anyway) could survive without ragwort, when the evidence says not. It even seems that he has claimed that the moth is poisoned by this plant when it is its main a natural food.

To people reading this blog I say nobody should be harassed but when an academic seems to make claims apparently using poor evidence and doesn't seem to check his facts then he deserves some criticism.

The is an old Dutch proverb that seems to fit this situation. "He who burns his buttocks must sit on the blisters"



 

ragwort outbreak panic up north

Today's entry is abut a ridiculous article that appeared in the Northern Echo

Apparently there have been "ragwort outbreaks in Weardale". One does wonder if there have been outbreaks of daisies or dandelions. This sort of language suggests that ragwort is spreading when we know that it has been there all along and that it is , if anything, declining in abundance. It quotes a local Cowshill resident Ian Reedman.

“It is poisonous to horses and potentially to humans. People need to be aware of it and report it to the authorities. The only way to get rid of it is to pull it out of the ground."

To those of us in the know of course this panic seems rather foolish. There is no reason to panic about this native wildflower as it is only rarely any problem. Oak trees are poisonous too but we don't panic about them. Ragwort is a bit more poisonous but there are no records of anyone every being poisoned in the UK.
You would have to eat quite a bit of it and horse problems as I blogged this week seem to be rather exaggerated. and when the exaggerations were examined by the Advertising Standards Authority adverts were stopped

It is the silly season and with all the politicians on holiday we get this nonsense every August.

More foolish ragwort comments from an equine professional

A while ago I posted an account of how the BBC had encouraged law breaking on ragwort.
and that they had broadcast a statement from someone who had contacted them making the silly claim that ragwort was not a native plant.

I regularly post accounts of how equine professionals seem to  make silly and ignorant statements on ragwort. Like this one where a vet posts a link to really nutty material or this one on the same nutty material and on getting the law wrong. and as I have blogged before  it seems even an equine veterinary professor is not beyond making quite serious mistakes.

Well I have tracked down the originator of the statement. He has, it seems, been bragging about it on facebook on a page commenting about the BBC programme.

Richard Halls Had my say last night, one group was saying ragwort was ok. I said its[sic] not native coming from South America and was spread by the railways.

Mr Halls is of course wrong. The ragwort in question is a native plant. He will have quite well have had botanists groaning around the country at this foolish ignorance. There is a ragwort that is reckoned to have spread around the railway network but this is a very different and smaller plant called Oxford Ragwort. It doesn't come from South America but from Mt Etna in Italy.

But the facebook account reveals more. He is an Equine Dental Technician. This is is yet another example of the phenomenon, perhaps caused by the nonsense in  the press,of an equine professional not knowing their stuff.

 

Who tells the ragwort truth?

Today's blog entry is inspired by the following tweets.

Man in Black ‏@Asatru69 3h

Over 2,000 horses die a year as a result of RAGWORT poisoning. Time to completely eradicate this horrible plant.

And then after being  pointed to an article saying this wasn't the case by ragwort expert Esther Hegt

Man in Black ‏@Asatru69 2h

@Ragwort_horses There seem to be as many articles 'for' Ragwort as there are from those 'against'. Who is telling the truth then?

How do we know what the truth is? Well we use the scientific method and evidence. With the 2000 horses figure we can actually show that these figures were examined in advertising by the Advertising Standards Authority.(ASA)

They are independent body who look at the evidence. Those adverts are no longer there because the ASA took action and the companies could not provide the evidence.

( That blog entry talks about the nonsense figure of 6500 deaths but there was one company saying 2000)

The problem is that there are two groups of people involved. There are people like me and Esther who look

at the science and there are people who just repeat what they have been told.

On Twitter Esther advised asking the University of Liverpool. The death figures are often claimed to be from data collected there.  As she knows I have already checked with them they recorded not one single death over a five year period.

Anyone wishing to do so can read about the circumstances surrounding this at a blog entry I made this week.

In regards to what happens if you look at the scientific evidence Esther Hegt is a prime example.

She once  believed the nonsense , but she is a good scientist and looked at the evidence.

It is the evidence that says it is nonsense.