[BBC News] Warnings over 'dangerous' weeds

[Frances]

I'm surprised that no-one has commented that Wild Oats are also included under the Weeds Act 1957 - who has been sowing these recently ?

[Mutley]

You'd have thought that after all these thousands of years horses and cattle have been living in the counrtyside they would have learnt that hogweed, or whatever, will kill them if they eat it. Stupid animals.

 

After the demise of hedge schools in the late 19th century there was a marked decline in most bovine studies; advanced botany and languages dying out almost completely.

[Fossils]

[*]Poisoning can occur at ANY time of the year Ragwort poisoning destroys the liver, leading to slow, painful death Poisonous to most animals but horses and cattle are most susceptible<LI class=bold>Once symptoms have appeared in an affected animal little can be done and it will usually die

[*]Acts in a cumulative fashion - a small amount eaten over a period of time is just as damaging as one large dose<LI class=bold>Animals eating 5 percent or more of their total daily diet of ragwort for periods exceeding 20 consecutive days can be expected to die within a 6-month period

[*]The plants

1st year - rosette stage - most poisonous

2nd year - stem/flower stage - each plant can produce 150,000 seeds, with a 70% germination rate

[*]A horse can get ragwort poisoning without actually having any plants in their paddock! Seeds/spores from plants in neighboring fields can blow over and contaminate a paddock apparently free from plants. A horse can eat or inhale these - and cumulative poisoning can begin.

[mollag]

Genesis warned you in 1971 on Nursery Crime, but did you listen? no

[Hugh Jampton]

My girlfriend has a horse which she puts into a "starvation paddock" to get the horse's weight down. The hose has eaten every blade of grass down to its roots but has left to cushag alone. As the cushag dies off after flowering it may get eaten so we have dug up all the cushag in the paddock and the field. This has been an annual event.

 

I still have Genesis' warning

[jimbms]

Genesis warned you in 1971 on Nursery Crime, but did you listen? no

Yes I heard them tell me that at Reading 1973 when I was suffering the effects of another more happy weed. Peter Gabrial appearing out of the rising flourescent pyramid nearly did my head in.

[Sneak]

Quite often Ragwort grows amongst other vegitation like grass and when the Horses or cattle are grazing, over a fence or bank, they grab a mouth full of it and don't realise. Apparently the ragwort tastes sour and this is when the animals drop it but sometimes it is too late.

 

Next time you are heading to B & Q or th Post Office have a look at the banks which run along the side of the road and you will see the Ragwort - it has yellow flowers.

 

In fact it grows everywhere, I don't know who is supposed to be in charge of pulling it up along the side of the roads.

[Sneak]

Research shows that Ragwort is toxic to animals. Many reports in the press in the UK do not, however, derive their information from proper scientific sources. What is overwhelmingly clear from the scientific journals is that actual poisoning is a rare event. Detailed questions on the number of horse deaths are dealt with here Ragwort horse deaths and the matter of human toxicity is dealt with here Ragwort humans The rest of this article deals with general toxicity.

 

Common ragwort contains compounds that are poisonous to most vertebrates .These are pyrrolizidine alkaloids . These substances occur in other plants as well. In fact they occur in 3% of the world's flora

 

(1). Inside the plants, they occur in a non-toxic form, but after the plant has been eaten it is first changed by the intestines and then broken down by the liver. Both these processes are necessary for toxicity. (This is also why it is not dangerous for humans to handle ragwort.) The breakdown products formed in the liver are toxic.

 

(2, 3). Contrary to what is often thought by the general public, the alkaloids do not accumulate inside the body of an animal. The fact is that they are excreted in about 24 to 48 hours

 

(3). It is the damage that is caused to liver cells that can, if sufficient ragwort is consumed at each dose, be cumulative to the point of death occuring.

 

The question then is how much needs to be consumed for an animal to be poisoned. Again research provides the answer. It has been found that is lies between 5 % and 25% of body weight for horses and cattle. For goats the figure is much higher, between 125% and 404% (4).

[Frances]

so the Ragwort can continue as Mann's 'offical' flower pace joke by Gov Raglan about 100years ago - its toxity is wildly exagerated ?