Death cap toadstools are extremely poisonous and hard to spot. According to BBCHome.com, 90 per cent of all deaths from mushroom poisoning are caused by the death's cap mushroom, or Amanita phalloides. There is no cure or antidote for death cap toadstool poisoning, and symptoms usually don't show up until 24 hours after ingestion. Damage to the body can be severe enough to require transfusions, dialysis and even transplants of the liver or kidneys, none of which may work to save a life. Identifying wild mushrooms is harder than you might think, and the consequences of being wrong can be tragic.
Note the time of year. Death cap toadstools generally appear in late summer through early winter. Don't let that be your only guideline, because this can vary according to the climate where you live.
Look closely at the surroundings of the mushroom in question. Death cap toadstools often -- but not always -- grow at the base of trees. The enthusiasts at Mushroom-Appreciation.com state that they often grow at the base of oak and pine trees, though they have been found by beech, birch, chestnut and spruce trees.
Check the colour and size. Amanita phalloides mushrooms are generally yellow or greenish, but can also be brown. Mature mushroom caps can be 6 inches across, but when they are young, they resemble button mushrooms, so don't go by size alone.
Look at the underside. The fluted gills on the underside of the cap are usually not attached to the stem. There may also be a ring around the stem right beneath the cap. In young death cap mushrooms, a thin membrane may trail from the edge of the cap to the stem.
Dig around the base. Death cap toadstools have a white sac at their base called the volva. All Amanita mushrooms share this characteristic. The sacs can disintegrate or be broken off, so if your mushroom has any of the other characteristics of Amanita phalloides and no sac, it is not safe to eat it.
Smell the mushroom. Death cap toadstools have a light scent that is reminiscent of roses. Scent is subjective, so if the mushroom you are examining has other characteristics of the Amanita phalloides, but does not smell like roses to you, don't eat it.
Contact local wildlife authorities if you think you have come across death cap toadstools, so that a public warning can be posted.
Do not eat wild mushrooms without having an expert examine them to make sure they're safe.