Fungi

You can’t without identifying the fungus and that is not always easy. Literally thousands of species of fungus occur in Britain; only a few are really good to eat and only a few are deadly poisonous.

The old wives’ tales that only edible fungi have a peelable ‘skin’, do not blacken a silver spoon (!) when cooking and smell like mushrooms, are all totally wrong!

Most fungus fatalities in Britain (about one each year) are caused by the death cap which has white gills, a ring (or ‘collar’) round the stem and, usually, a greenish cap.

Picture by Cheryl Dye

Fairy rings are caused by the outward growth through the soil of fungal mycelium from the point where it originated from a spore. A number of toadstool species cause rings of darker (and often longer) grass where the fungal activity has released nutrients which fertilise the grass. In late summer or autumn fungus fruiting bodies (toadstools) may emerge in this dark zone. Some other ring-forming species ‘fruit’ without affecting the growth of the grass.

A well-fed lawn is less likely to show fairy rings – but also less likely to provide a habitat for interesting plants and fungi. It is said that watering the lawn with a dilute solution of Epsom salts (magnesium sulphate) will eliminate fairy rings but the best answer is to enjoy them! If you have young children, make up stories about the rings; if you have scientific inclinations measure the growth rate of the ring – typically 10-20cm in diameter each year.

Picture by Cheryl Dye

Honey Fungus is the commonest of the toadstools which form large clusters at the base of trees and stumps. The caps are often honey-coloured, sometimes darker, usually with small scales. The gills are pale brownish and there is usually a ring (or ‘collar’) round the stem. Another clue is the presence of tough black threads (‘bootlaces’) under the bark of affected wood. In fact, this fungus is one of the most variable of our common fungi. The other common clustering fungus on stumps is Sulphur-tuft, smaller and yellower than Honey Fungus and it has dirty-greenish gills. It does not attack living trees.

Honey Fungus is a killer of trees (and some herbaceous plants) but it can take several years after the appearance of the toadstools before the tree dies. Removing them won’t help because it is the mycelium within the tree’s tissues which is causing the harm. Honey Fungus continues to consume the wood after the death of the tree.

Preventing the spread of the fungus is a major undertaking (involving digging, plastic barriers and a fungicide called Armillatox) but is rarely worth the effort. The good news is that it typically attacks the odd tree and rarely decimates a garden or wood.

Picture by Elizabeth Dack

The risk is small but not zero. Most lawn toadstools are harmless but some of the small brown ones can cause upsets and hallucinations. The only seriously poisonous toadstool which is common on lawns is the Ivory Funnel-cap (and its very similar relative). This has a creamy-white cap (sometimes with a hint of pink or grey) 2-4cm across and often slightly irregular (not really funnel-shaped despite the name). The gills are similarly coloured and quite crowded (closely spaced). It often occurs in loose clusters. Dogs have been known to die from its ingestion but human fatalities are rare and may never have occurred in this country.

Picture by Howard Stone

It depends who you are and where you are! In Britain the word mushroom is usually reserved for members of the genus Agaricus of which nearly 40 species have been recorded (many of them uncommon and difficult to distinguish). Most mushrooms are edible but the Yellow-staining Mushroom is seriously poisonous. All the rest of the fungi with stems and caps (agarics) are lumped together as toadstools. The derivation of this word probably has more to do with tod, German for death, than it does with the amphibian.

In North America the word toadstool is not used at all, and all larger fungi (even non-agarics like bracket fungi) are called mushrooms.

Picture by Cheryl Dye

The safest way to learn about fungi is to attend a fungi foray led by an expert. Autumn is a good time of year to see fungi, so look out for guided walks and events in your area during the autumn months. Organisations which host fungi forays include Norfolk Wildlife Trust, Sculthorpe Moore and Pensthorpe Nature Reserve and Gardens.

The East of England Tourist Board lists all wildlife events in East Anglia, so this is a good place to keep up to date with any fungi forays happening in your area. See www.visiteastofengland.com for more information.

Norfolk and Norwich Naturalists’ Society have a Norfolk Fungus Study Groups for further information visit http://norfolknaturalists.org.uk/wp/recording/specialist-groups/nfsg/

For lots more information about fungi, visit the British Mycological Society, at www.britmycolsoc.org.uk.

Picture by Jenny Johnson

It is impossible to be completely certain of how many species of fungi occur in a particular locality. Fungi are not a well-studied group, and are easy to miss, as the length of time between the emergence of a fruiting body and its decay can be very short. The British Mycological Society compiles a list of fungi species recorded throughout Britain, called the Fungal Records Database of Britain and Ireland. This database lists 2,289 species of fungi recorded in West Norfolk, and 3,262 species recorded in East Norfolk.

Picture by Ray Watson