Knowing and being able to accurately identify which wild plants and fungi are poisonous is vital for a forager. There is also a certain morbid fascination that can be experienced when you come across a deadly species just happily growing in your locality. I don’t want to put people off foraging, but knowing the dangers is a sober reminder not to be silly with identification of anything you plan to eat and even handle.
Since I have consistently found this species around the Colne Valley, I shall make my point by talking about the king (queen??) of deadly fungi – the Deathcap (Amanita phalloides). Around 30g or half a cap is estimated to be enough to kill a human, and it is advisable to avoid touching it or at least to wash hands thoroughly after doing so. It has some key identification features: firstly, like all Amanitas, the entire mushroom, cap and stem, emerge from an egg-like sac called a volva, as you can see here. This is a vital identification feature, but may require clearing some debris around the base to see if it is there, and if not, it may have broken away so be sure to use other features too!
However, if there is a volva, just avoid it, as there are many other poisonous Amanitas such as the beautiful Fly Agaric (Amanita muscaria) and deadly Destroying Angel (Amanita virosa).
The other important features are that the 5-12 cm diameter cap is usually greenish or yellowish olive with fibres radiating from the centre giving a subtly streaked appearance (a rare white form can also occur). The gills are white and there is usually a ring on the stem with grooves on the top. I find the smell is also key, unforgettably sickly and unpleasant. It is unfortunately common in woodlands or under trees on grass, usually occurring in large groups.
Here is a clear case of avoiding common mushroom edibility myths such as mushrooms that have peelable caps or can be eaten by other animals are safe. The Deathcap not only peels, but is eaten quite happily by slugs and rabbits.
For those that have an appetite for the macabre, keep reading, and I will discuss the unpleasant way this mushroom kills:
After ingestion of the mushroom (cooking does not destroy the toxin) there is a delay of 6 to 24 hours before any symptoms occur. The unfortunate person then experiences gastrointestinal symptoms including abdominal pain, prolonged and violent vomiting and diarrhoea. This lasts for 12 to 24 hours and then the patient makes an apparent recovery. This is sadly not to last, as the toxin, Amanitin, is attacking the cells of the liver and kidneys, manifesting after a period as pressure sensitivity over the right hand rib/abdomen liver area, yellowing of the skin and eyes (jaundice), bleeding from the intestines and psychological disturbance, with eventual coma, liver and kidney failure and death within a few days. The best of modern medicine still has no antidote for the toxin, though with treatment the fatality rate drops from 50-90 per cent to 20 per cent in adults and 50 per cent in children. Treatment should be applied as early as possible with stomach washes of activated charcoal to bind the toxin and blood treatments such as haemodialysis.
In case this has put you off foraging, to get things in perspective, it is actually quite straightforward to identify the Deathcap once you are familiar with its key features – greenish cap, white gills, white ring on stem and white bag at the base. Fatalities in the UK are around one person per decade. However, it is a reminder to be ever-vigilant and sensible when foraging. If you want to see some ‘in the flesh’ so you can be sure to know what to avoid and are in the locality, I’ll be happy to show you some.