Stinking brittlegillRussula foetens

The stinking brittlegill (Russula foetens), also called the stinking russula, is listed as inedible in British and Western European field guides, and some authors consider it toxic. In Ukraine and Russia, where it is known as valuy, it is classed as conditionally edible: people eat it only salted, after several days of soaking and a boil. We don't recommend picking it, and it should never be eaten fresh or lightly cooked.

Several features together give it away. A young stinking brittlegill looks like a tight fist: a rounded honey-yellow to ochre cap pressed hard against a thick white stem. The cap then opens to 5–12 cm, sometimes wider. It is slimy after rain, and the margin has deep radial grooves with small bumps. The gills are cream with rusty spots and often carry clear droplets. The stem is white, browning at the base, and soon goes hollow and crumbly inside. Then there's the smell: strong and unpleasant, like rancid oil, turning fishy in old specimens.

It grows across Europe, Ukraine included, in damp broadleaf and mixed woodland under oak, birch, beech, hornbeam and aspen, less often under spruce and pine. It is mycorrhizal and grows on the ground, singly or in groups, often along woodland paths. It fruits from early summer to mid-autumn and is most plentiful in high summer.

Is it edible? That depends on whom you ask. Ukrainian and Russian foragers have long salted it, and a 1979 Ukrainian handbook calls it conditionally edible. British, German and Scandinavian guides call it inedible because of its bitter, burning taste and foul smell, and First Nature notes that many authorities regard it as toxic. Yet the Polish monograph on brittlegills (1998) states plainly that it is not poisonous, and Norway's list calls it "not food" rather than poisonous. We found no published poisoning case for this particular species, but that doesn't prove there are none: acrid brittlegills eaten raw or undercooked are known to cause stomach upsets. Where it is eaten, only young closed caps are used, peeled, soaked in cold water for days with frequent changes, boiled, drained and then salted for a month or more.

How do you tell it from the poisonpie? In Ukraine and Russia the poisonpie (Hebeloma crustuliniforme) is literally called the false valuy, and it is poisonous: vomiting, diarrhoea and stomach cramps begin a few hours after the meal. Its cap is also yellowish brown, its gills can also weep droplets, and it smells of radish or raw potato. The surest difference is the spore print: brown in the poisonpie, cream in the stinking brittlegill. The poisonpie's gills turn clay brown with age, its cap margin is smooth rather than grooved, and its stem is fibrous and bends. The stinking brittlegill's stem is thick, hollow and snaps like chalk. If vomiting or diarrhoea starts after a wild mushroom meal, call 112 (999 in the UK) and say you ate wild mushrooms. If nausea and diarrhoea begin six hours or more after the meal, a death cap may have ended up in the basket: treat it as an emergency, even if you feel better for a while.

Other look-alikes. Russula subfoetens is a little smaller and practically impossible to separate in the field, so foragers treat the two as one. Russula grata is smaller and smells pleasantly of bitter almonds rather than rancid oil. The crab brittlegill (Russula xerampelina) can smell of fish too, but it is edible, mild-tasting, with a purple to brown cap without deep grooves and a stem often flushed pink. The ochre brittlegill has no strong smell, no grooved margin and a solid stem.