Shiitake

How to recognise it

The cap is brown to dark reddish-brown and flattens with age. It often has whitish flecks near the edge and it cracks in dry weather. The gills are white to cream and bruise brown. The stem is tough, fibrous and often off-centre. The spore print is white. The deadly funeral bell (Galerina marginata) also grows on logs. It is smaller and honey-brown, with a ring on the stem and a rusty-brown spore print.

Where it grows

Shiitake is native to East Asia, where it grows on dead broadleaf wood such as oak and Castanopsis. In Europe and North America it is grown on oak logs or sawdust blocks. It has been found outside cultivation only a few times, for example in the Netherlands. So a brown mushroom on a fallen log in the woods is almost certainly something else.

When

Logs kept outdoors fruit in spring and autumn. A flush comes a few days after soaking rain in mild weather. Growers also force a flush by soaking a log in cold water.

Picking

Pick the caps while the edge is still curled under. Twist them off or cut the stem at the log. Pick only from logs you grow or have permission to pick from.

Cooking

Make sure of the identification, then cook it thoroughly. Raw or lightly cooked shiitake can cause shiitake dermatitis. That is an itchy rash of whip-like streaks, about a day later. The stems are too tough to eat, but they flavour stock. Fry or simmer the caps with soy sauce, ginger and garlic. They have a deep, savoury taste.

Keeping

It keeps a few days in the fridge in a paper bag. It dries very well. Soak dried caps before use and keep the water as stock.

Toxic look-alikes

• Galerina marginata · Deadly - do not eat