How to tell White knight from Destroying angel

The cap is 4–10 cm across. Young caps are conical to convex with an inrolled margin, then flatten out around a small, low boss, often with a wavy edge. In the white knight the margin is smooth; a ribbed margin points more to the chemical knight of birch woods.

The colour is white to cream, sometimes with a pale yellow tinge. With age the centre turns ochre or yellowish brown, and old caps develop ochre spots. The surface is dry, matt and smooth, and stays dry even in rain.

The cap is 5-12 cm across, egg-shaped when young, then bell-shaped or conical, often slightly lopsided, and finally spreading with a boss. It is entirely white or creamy white, slightly yellowish in the centre in old mushrooms. The surface is smooth and slightly sticky in wet weather. The mature cap has no scales, no warts and no veil remnants (unlike the fly agaric or Caesar's mushroom).

The gills are white, later pale yellowish, thick, fairly distant and of unequal length. They are clearly notched just before the stem, and their edges are finely toothed.

The spore print is white. Pink or chocolate-brown gills mean a field mushroom relative; gills running down the stem point to a funnel.

The gills are white and free (not attached to the stem) and moderately crowded. The spore print is white. As in the rest of Amanita section Phalloideae, to which this species belongs, the gills stay white and free even in mature mushrooms, unlike those of Agaricus.

The stem is 3–8 cm tall and 0.8–1.5 cm thick, cylindrical, sometimes slightly wider at the base. It's white to pale yellowish brown, powdery at the top, finely fibrous lower down, and slowly browns when handled.

There is no ring, no veil remnants and no bag-like volva at the base. If you find such a sac, you're holding an amanita.

The stem is 8-15 cm tall and 1-2 cm thick, cylindrical, long and slender, with a sac-like volva at the base (a remnant of the universal veil that looks like an eggshell). It is entirely white. Near the top is a white membranous ring, firm in young mushrooms and sometimes gone in old ones. The stem surface often has thin white flaky scales and fibres.

The flesh is white and firm, thick in the cap, and doesn't change colour noticeably when cut (some authors note a faint pink tint). The taste is acrid and burning, with bitterness.

The flesh is firm and entirely white and doesn't change colour when cut, like many edible mushrooms, so that tells you nothing. The smell is like radish in a very young mushroom, then turns unpleasant and sickly sweet, sometimes with a hint of chlorine, hence the epithet "stinking" in its Ukrainian name. In young mushrooms the smell is still faint, so don't rely on it as the only sign.

The smell is strong and unpleasant: sharp like radish, with a sickly sweet note of honey and a mealy edge when cut. Young specimens smell less, mature ones can be smelt from a distance. A nauseating chemical smell, like cooked beetroot or coal gas, belongs more to its relatives, the chemical knight of birch woods and the gassy knight (Tricholoma inamoenum).

Faint, unpleasant and sickly sweet, sometimes with a hint of chlorine, especially in old mushrooms and when the flesh is damaged. It tells you nothing about safety: the smell develops only with time, and a young mushroom with no distinct smell can still end up in the basket and cause fatal poisoning.