Fairy inkcapCoprinellus disseminatus

The fairy inkcap (Coprinellus disseminatus), also called the trooping crumble cap, almost never grows alone: around an old stump or on a rotting log its tiny bells come up in tens and hundreds, like a scattering of buttons. Each cap is only 0.5 to 1.5 cm across, cream at first and then grey, with an ochre-brown centre. Unlike most inkcaps, it doesn't dissolve into ink; within two or three days it simply greys and blackens.

How do you identify a fairy inkcap? The cap is bell-shaped, 0.5 to 1.5 cm across, occasionally 2 cm, pleated from the margin almost to the centre, and finely hairy and granular under a hand lens when young. The gills are fairly widely spaced for an inkcap, white at first, then grey and blackish. The stem is slender, 1.5 to 4 cm tall and just 1 to 2 mm thick, white, translucent, hollow and very fragile, so the caps crumble as soon as you handle them. The spore print is black to blackish brown. The best clue is the sheer number of identical tiny caps covering a stump and the ground around it.

Where does it grow? On dead broadleaved wood: old stumps, roots, buried wood and wood chips, so it can seem to grow from bare soil or a lawn, but there's always wood underneath. You'll find it in woods, parks, gardens and hedgerows. It's very common, mostly from late spring to late autumn, in greatest numbers in autumn, and can fruit several times a year.

Is the fairy inkcap edible? Not really: it's tiny, thin and crumbles away. A few guides call it edible but not worth the effort, while most treat it as inedible. We found no reports of poisoning, and no tests for coprine or hallucinogenic compounds in this species, so there's no evidence that it's psychedelic.

What can you mistake it for? The glistening inkcap is bigger and honey brown, with glittering grains, grows in dense tufts rather than scattered troops, and dissolves into ink. Its closest lookalike, the pygmy brittlestem (Psathyrella pygmaea), also grows in small groups on stumps and can only be told apart reliably under a microscope. Bonnets (Mycena) have smooth, unpleated caps and a white spore print. The real danger lies elsewhere: among small brown mushrooms on rotting wood you may find the deadly funeral bell. It's bigger, has a ring or ring zone, a smooth cap and a rusty-brown spore print. So don't pick little mushrooms from stumps without experience. The liberty cap grows in grass, not on wood, and has a pointed cap.

Its English name fits well: a troop of fairy inkcaps around a stump really does look like a tiny fairy village.