Knowing what’s definitely edible is good, but knowing what will probably kill you is better. Here’s a few very dangerous common mushrooms, all of which would fall foul of the ground rules I set out in in my post on edible mushrooms – but it’s still worth taking some time to familiarise yourself with them.
The most dangerous can cause unpleasant symptoms even when touched with a bare hand (their toxins enter the bloodstream through the skin). If you’ve unwittingly carried one home in a basket or bag with other (edible) mushrooms before identifying it, you’d be well advised to throw the whole harvest out rather than risk cross-contamination.
1) Death Cap [Amanita phalloides]
Accidentally eating a Death Cap is a cause for immediate hospitalisation. This one species is responsible for the majority of fungus fatalities around the world, usually through liver and kidney failure. The toxicity is not reduced by cooking.
It has the form of a ‘standard’ mushroom – stem, cap, and gills on the underside of the cap. The mature cap is green, all other parts are white (it also gives a white spore print – a mushroom cap placed on a piece of paper overnight will drop its spores, aiding identification in some cases). Young specimens are covered by a ‘universal veil’, a shroud of thin white skin that the cap tears through, sometimes leaving traces on the cap and usually leaving a ragged ring about halfway up the stipe (stem) and a bulbous remnant at the base of the stipe. The white gills, the white ring and the white, bulbous base can occur on edible species, but are clear warning signs of the possibility of being poisoned.
Death Caps are generally found close to oak trees, but also among other deciduous (and sometimes coniferous) tree species. There is a possibility that an immature Death Cap could be confused with a puffball – they’re both small, rounded, white and growing among grass (though puffballs tend to show up in fields rather than woods). A puffball will be approximately spherical and solid white inside (once it starts forming dark spores it becomes inedible) – the Death Cap should show some indication of its eventual shape, and of its gills (puffballs have neither gills nor pores).
A close contender for Scariest British Mushroom is the Destroying Angel – it carries the same toxins as the Death Cap, and should be treated with the same caution. It’s not as common as the Death Cap, but just as deadly. The two share other similarities – they take the same basic form, only the colouring differs: the Destroying Angel is entirely white (again with a white spore print).
3) Panther Cap [Amanita pantherina]
Are you noticing a trend? The Amanita genus contains several edible mushrooms but also most of the really nasty species too. The Panther Cap (and the Fly Agaric, below) may not kill you, if you’re reasonably fit, but you’re unlikely to enjoy the experience. Both contain psychoactive substances that have been valued by shamanic cultures around the world, but there are considerably more palatable (and safe) ways of expanding your mind or altering your state – meditation perhaps, yoga (good for mind and body), or a glass of red wine and a snuggle on the sofa.
The Panther Cap shares the white stipe, with ring and bulbous base, white gills, and white spore print of its slightly deadlier relatives. The cap itself is brown (generally hazel brown, but the colour will deepen with age) and flecked with remnants of its veil. It has an odour of raw potatoes to it.
4) Fly Agaric [Amanita muscaria]
The Fly Agaric is the red & white-spotted fairy toadstool so often seen as the seat or home of fairies and other fey creatures in illustrations. Like the other Amanitas in this list, it’s mostly white, with the ring and bulb on the stipe and flecks of its veil adhering to the upper surface of its red cap. Be cautious – the veil remnants can be washed off by rain or removed by animal activity, and the cap colour can show as orange or reddish-brown depending on age. Again, the presence of white gills, white stipe ring and white bulbous base should be enough to deter the amateur forager.
5) Fool’s Funnel [Clitocybe rivulosa]
Another white-gilled mushroom, whose flesh and cap can take on a pale brown/pink hue when well-hydrated. It has another common name – the sweating mushroom, named for just one of the unpleasant symptoms it will produce if ingested. Some white-gilled mushrooms are edible, and very good, but for safety’s sake it’s best not to gather or eat mushrooms with white gills until you’re 100% confident of your identifications.
6) Devil’s Bolete [Boletus satanas]
A pored mushroom – the underside has a spongy, pored surface where typical mushrooms have gills. Like many boletes, it has a stipe that can be almost as thick as the cap is wide. There are some warning signs – the broad white cap looks a little like a skull in the grass, and the mature mushrooms smell of carrion. But this is one of the colour-changing mushrooms. Cut the cap in half and keep an eye on the yellow flesh – if it takes on any hint of blue on exposure to air, discard it (again, you’ll lose some good eaters, but you will minimise the risk of severe food poisoning)
7) Yellow Stainer [Agaricus xanthodermus]
This has a similar form to the Amanita species above – but the gills are not white. It will generally have the white ring around the stipe and the white bulbous base, though these can be absent. The key indicator, as the common name suggests, is that the flesh stains yellow when the mushroom is cut in half.
Just as with the Devil’s Bolete, any colour change should be enough to discard a specimen – at the loss of some good eaters, but safety first please, until you’re certain of your identification skills.
Mushroom Poisoning – What to Do?
I have collected, cooked and eaten wild mushrooms for more than 20 years, and never once had even a slight stomach upset. But it pays to remember that some mushrooms are deadly. The effects of mushroom poisoning include nausea, vomiting, cramps, and diarrhoea. Profuse sweating may also occur. Symptoms can show quite soon after eating, but it often takes several hours for the poisoning to become apparent.
If you suspect a case of mushroom poisoning:
* Phone 999 for an ambulance, or take the person to the nearest hospital (or vet, of course). Some toxins become considerably more serious the more time elapses between consumption and treatment.
* Do not try self-treatment through induced vomiting – it is unlikely to be helpful unless the mushrooms were consumed at most a couple of hours previously. Charcoal tablets can have a negative effect.
* Gather up any remaining mushrooms, including leftovers, discarded parts and even the vomit if you can. Some of it may help identification (and thus appropriate treatment), the rest should be disposed of carefully (including any edible species you may have gathered at the same time, which may be contaminated).
Steve Wallis has been foraging for fungi since 1993, with years of experience working on a wild site of woodland and heathland in the New Forest. Steve believes that good mushrooms are going to waste, because we regard them all (in the wild) with suspicion – even though we readily learn to distinguish sloe and elder, for example, from all the poisonous berries.