Inkcaps are one of the more common fungi I encounter in the autumn, seeming to pop up on lawns and other grassland all over the place. They are named for their habit of rapidly decaying into a sticky black inky mess, in a process called autodeliquescence. The two most common forms are the Shaggy Inkcap (Coprinus comatus) and the Common Inkcap (Coprinus atramentarius). I captured some of the latter in various stages of development.
If you plan to eat them it is worth knowing the difference as, despite both being edible, if you eat the Common Inkcap and have consumed any alcohol with your meal or in the past 72 hours or in the 72 hours afterwards you will experience alarming symptoms of feeling very hot, red face, palpitations, shortness of breath, sweating, tingling limbs and sometimes a headache. It is because of this unusual property that it was given to alcohol abusers to help overcome their addiction by providing a strong deterrent. On another practical note, the Common Ink cap lives up to its name, as black drawing ink can be made from the deliquesced caps by boiling them with a little water and cloves.
Both of the Inkcaps above are very readily identifiable. The Shaggy Inkcap looks like a white drumstick, with a cylindrical white cap and thick white stem, sometimes showing a loose white ring, though this may fall to the base of the stem. The cap feels loose and can be wiggled around on the stem that it encircles. The gills start white but then quickly turn pink before becoming a black mush. A key feature of the Shaggy Inkcap is that the surface of the cap breaks up into large, shaggy brownish-tipped scales.
By contrast, the common inkcap has a smooth, shorter, fatter and more conical cap that is greyish. It usually had striation on the cap, and the cap margin usually splits in older specimens.
The Shaggy Inkcap should only be eaten when the cap and gills are still young and white. It can be chopped up into rings like calamari, but I am not overly impressed by it and echo John Wright’s sentiment that it tastes akin to boiled polystyrene. It is, however, so common and easy to identify that it is a good choice for trying your first wild, foraged mushroom, though I suspect I haven’t sold it well. Don’t be disheartened, you may find a superior way to cook it and think it is delicious!