MASSES of Britain's deadliest mushrooms which kill 90 per cent of people who eat them have been 'madly' springing up across the country.

Foragers are being warned about an alarming abundance of toxic 'death cap' mushrooms this autumn, blamed on recent hot and humid weather.

5 The lethal mushrooms are Britain's deadliest and have been springing up all over the country Credit: Alamy

5 Mushroom foragers have been warned about the toxic toadstools which look like edible varieties to the untrained eye Credit: Getty Images

Just a small amount of the lethal fungi, which looks like a normal mushroom to the untrained eye, causes internal organ failure for which there is no treatment.

On Tuesday a three-year-old boy died after he is believed to have eaten a death cap during a family day out mushroom-picking in Victoria, Canada, reports Fox News.

Keen mushroom forager Rob Parkinson, 43, posted pictures of a large crop of death caps he spotted bordering a football pitch in Bournemouth.

The experienced forager said he had never come across so many death caps in such a concentrated area before.

"It would only take a small amount to cause a pretty horrible death," he said.

5 Credit: Alamy

"I was worried because they were in a public place with children and dogs all around, if they did ingest a death cap it wouldn't be pretty."

After eating one, the victim will not normally show symptoms for the first 24 hours. After that they will suffer diarrhoea, nausea, vomiting and cold sweats as the poisons destroy the internal organs.

In 2008 a 38-year-old woman on the Isle of Wight died a painful death after she ate the wild fungi with a meal of sausages after a relative picked it without realising what it was.

Now experts are advising the public to only forage for wild fungi if they know what they are doing after reports of 'masses' of death caps springing up in concentrated areas of the country.

While the toxic toadstools - Amanita phalloides in Latin - have always been common in the UK it is believed that recent mild and damp conditions has caused them to 'fruit madly' in some wooded areas this year.

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In south Wales there have been reports of 'masses and masses' of death caps in woodland.

To the uninitiated the toadstools look like any other mushroom but stand out due to the pale green colouring of their caps, a bulbous end at the foot of the stalk and an annulus - a ring-like collar - at the top.

When ingested, the phallotoxins and amanitins toxins attack the liver and kidneys causing renal failure. There is no cure for it, which is why they have such a high mortality rate.

Lynne Boddy, of the British Mycological Society and a professor at Cardiff University, said: "I am aware of increasing reports of death cap mushrooms this year.

How to spot a death cap mushroom BULB: Look for a whitish six-inch stalk with a large, round bulb and white sac-like 'volva' at the base GREEN: The cap will be between two and six inches across and olive green, pale green or yellow, and sometimes white or brown, with patches of thin white veil tissue BURIED: Dig into the soil to find the end of its stalk, which is often buried around the tree it is attached to. The bulb may break away over time so even if it isn't there, it could still be a death cap WAVE: The cap may have a flat, wave-like edge GILLS: Look for crowded white gills under the cap - many edible mushrooms have pink or brown gills SPORES: Look for a white spore print by placing the mushroom cap on a piece of paper overnight - death caps leave a white spore print while edible Paddy Straws leave a pink print SCENT: Smell the mushroom's flesh. A death cap mushroom smells slightly like rose petals

"Death cap fungi is native to the UK and Europe and is non-invasive.

"They are very important to the eco-system and do a very important job. People don't need to be scared of them as long as they don't go around picking up mushrooms willy-nilly and eat them.

"After I found out about the Bournemouth ones I gave a talk on fungi and somebody came up to me and told me they had noticed masses and masses of them this year in an area of south Wales.

"It could be they are fruiting madly this year because the conditions such as the temperature and the rainfall have been just right for them. If it is warmer they metabolise quicker.

"The fungi must also have enough nutrients in their fruit bodies for them to be bigger."

Death cap mushrooms grow on tree roots and if a tree has had a good year it has lots of sugars and nutrients to release.

5 The killer fungi look very similar to edible varieties of mushrooms which makes them extremely dangerous Credit: Getty Images

5 One of the differences is the colour of the mushroom's 'gills' underneath the cap, which are usually white for a death cap Credit: Getty Images

Mr Parkinson said he carefully removed the death caps he found in Queens Park, Bournemouth.

He said: "I do a fair bit of mushroom hunting and I have never come across anything like this before.

"I found about ten death cap mushrooms in a two metre area, there were more small ones on their way up, too.

"I have only ever found one or two at once before, so this was a bit of a bonanza.

"It's very rare to find this many at once. They're such magnificent mushrooms but they are the most deadly mushroom in the UK.

"The problem is that if a child did eat one then the parent would net necessarily know what happened or what to do.

"There was enough there to dispatch everyone at the park.

"I would usually leave these alone to get on with whatever purpose nature gave them but as it is a popular place for dog walkers and kids, and these were in a very open area, I decided not to.

"I took a few specimens to examine myself and very carefully bagged the rest up and put them in a bin.

"However, there will be more of these popping up over the next few weeks.

"If you happen across anything that looks remotely like these, don't touch them, and certainly don't take them home and make mushroom soup!"

Death caps mushrooms grow to up to 6ins tall and the cap can measures up to 6ins in diameter.

Roman Emperor Claudius in 54AD and Holy Roman Emperor Charles VI in 1740 are believed to died from eating death cap mushrooms.

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