There is something special about the first field mushroom you find and cook. It is probably one of the main mushrooms best eaten within hours of picking - it can be dried but is not worth it - it loses way too much flavour.


The Field Mushroom
Agaricus campestris

The Field Mushroom, Agaricus campestris, is the most commonly eaten wild mushroom in Britain. Its species name campestris is derived from the Latin word campus which means "field", and it is found most commonly in meadows grazed by horses, cattle or sheep. It can be found worldwide and appears in fields and grassy areas after rain from late summer through autumn. It is fast maturing and has a short shelf-life.

The dainty Field Mushroom grows alone, gregariously, or sometimes in fairy rings where it tends to stimulate growth of grass inside the ring. It is closely related to the cultivated white "button mushrooms" sold in grocery stores, but the Field Mushroom is smaller and rather more delicate in stature, while having the same characteristic mushroom smell.

The Field Mushroom, is a beautiful white edible that has a white cap, dry and silky when young, sometimes developing a few small scales as it matures and is 3-11 cm in diameter. The cap is convex at first before flattening out with maturity. Usually the margin remains down-turned or slightly in-rolled even when the cap has expanded fully. When young, the
cap is connected to the stem by a membrane (partial veil) which covers the gills, this tears as the cap expands and persists for a time as a narrow ring around the stem. The crowded gills are initially pink, then red-brown and finally a dark brown in maturity, and the spores are a dark chocolate brown. The white stem is 3 to 10 cm tall and 1 to 2.5 cm
in diameter, the stem is smooth above the single, delicate ring and somewhat scaly below. It is more or less parallel, sometimes tapering slightly towards the base, and does not turn yellow when cut. The taste is mild and pleasant, as is the odour. The thick flesh is white,
sometimes turning slightly pink or reddish when cut but never staining yellow.

Caution is required when identifying them for eating, as the Field Mushroom resembles some poisonous fungi, but the latter always bruise colourfully, have yellow or white gills, carry shingles on the cap, or smell strange.

A harmful species is Agaricus xanthodermus which can often be distinguished from the Field Mushroom by some flattening of the top of the slightly greyish-white cap in the early stages. It has a tendency to stain yellow where damaged, and has a strong odour often likened to iodiform or disinfectant. This odour may sometimes be too faint to be
recognised with certainty, however, if the mushrooms are kept in a plastic bag for fifteen minutes then sniffed, the odour will usually be sufficiently strong to be easily recognised. The inky scent of the poisonous yellow-staining mushroom comes from carbolic acid, which will cause a guaranteed tummy ache.

The green-spored parasol mushroom Chlorophyllum molybdites has grey or greenish-brown gills, and in North America is responsible for more cases of mushroom poisoning than any other species. The toxins in Chlorophyllum molybdites are usually not fatal but can make people seriously ill. It is a large attractive mushroom distinguished by its
gill and spore colour.

The Death Cap mushroom (Amanita phylloides) is extremely poisonous and is responsible for 90 per cent of all fungus-related poisoning deaths in Europe. The cap is light olive-green to greenish in colour. The gills can range from white to pinkish in mature mushrooms. In young specimens, a white, membranous partial veil tissue extends from the edge of the cap to the upper stalk, covering the gills. The stalk is white, up to 15 cm tall, with a large rounded bulb at the base. The bulb includes a white, cup-like membranous sheath at the base of the stalk (volva). The base of the stalk and the tell-tale volva are often buried in the soil. If you find a mushroom in its button stage and are unsure if it is edible, dig out the base of the stalk. If it is surrounded by a cup-shaped sac it is likely to be poisonous. It is easily distinguished from the Field Mushroom by the pure white gills which can turn to cream as they age.

Older specimens of Field Mushrooms may become infested by maggots, which enter the cap flesh via the gills. Careful inspection is necessary, and it is inadvisable to include very old specimens in collections intended for food.

Culinary uses of the Field Mushroom include sauteed or fried, in sauces, or even sliced raw and used in salads. You can broil, stew, bake or preserve the caps. Be sure to rinse well to dislodge any sand, and also watch out for the small, white larvae that tunnel through the stems and caps.

Cream of mushroom soup recipe (serves 4-6)

500g Field Mushrooms - cleaned and chopped
450g butter
1 onion - sliced thinly
900 ml milk
250 ml plain yoghurt or single cream
10 ml flat leaf parsley – chopped
chicken stock cube
salt
black pepper – freshly ground
nutmeg

In a large pan fry the onion with the butter until it is opaque then reduce to a gentle heat. Add the mushrooms and stir for 10 minutes. Add milk and bring to boil. Crumble in stock cube and season with salt and pepper. Add the parsley and simmer for 5 minutes then stir in the yoghurt and a pinch of nutmeg and simmer for 3 more minutes.