First Field Guide to Mushrooms of Southern Africa. Margo Branch

      Favolaschia thwaitesii is a tiny gem that grows saprophytically on rotting twigs and branches.

      The parasitic Artist’s Fungus, Ganoderma applanatum, causes heart-rot and death in oaks. Artists etch pictures in the white under-surface of young brackets, which stain violet-brown when scratched.

Symbiotic fungi

      SymbioticG fungi are fascinating because they form mutually beneficial relationships with their living hosts, which can be as diverse as termites, trees and algae.

      Lichen is a symbiotic partnership between an alga and a fungus. The alga is able to photo-synthesise and produce organic material, while the fungus absorbs water and mineral salts from the surrounding air or substrateG. This symbiotic relationship enables lichen to colonise extremely harsh places where little else can grow.

      Lichens are symbiotic partnerships between algae and fungi.

      Termites and mushrooms: Some mushrooms, such as I’kowe, a member of the Termitomyces species, (see page 26) are cultivated by termites in special fungal gardens. The termite mound is a marvellous growth chamber, with controlled temperature, humidity and ventilation. The partly digested plant material in termite faeces is a source of nutrition for the fungal garden, while the termites feed on fungal hyphaeG. The False Ink Cap grows on moist termite mounds in dry regions (see page 52).

      Termitomyces microcarpus mushrooms growing in soil that termites have removed from their nest.

Mycorrhizal fungi

      MyccorhizaeG form when fungal hyphaeG connect to the roots of a tree. The mushroom is able to absorb carbohydrates from the roots and, in return, makes minerals from the soil available to the tree, which improves the tree’s growth. Many mushrooms are thus closely associated with particular species of tree. Pines grow in poor soil and thus benefit from mycorrhizal fungi such as Pine Rings (page 30) and Ceps (page 40). The Poplar Bolete (page 42) occurs with poplars and the Dye-ball (page 51) with gums or black wattles. Foresters will often introduce the appropriate fungi into new plantations to stimulate the trees’ growth and facilitate the absorption of mineral elements, particularly phosphorus.

      Life cycle of a mycorrhizal mushroom

Features of mushrooms

      Cap shapes

      Gill attachment

      Gill spacing

Spores and spore prints

      The microscopic spores are an important feature used by scientists to identify mushrooms. They are consistent in size, colour and shape for each mushroom species. Although spores are too small for field identification, a spore print can be taken, which allows one to see the colour of the spores and preserve them for further examination. To take a spore print, simply cut off the cap and place it with the gill or pore surface down on a piece of paper. Cover it with a glass and leave it for a few hours. Use dark paper if the spores are pale.

      The shape of the pores and arrangement of the gills are also diagnostic features.

      A spore print showing the colour of the spores and arrangement of gills.

      Large dark spores of Shaggy Ink Cap, spindle-shaped spores of Pine Bolete, spiny white spores of Russula and light-brown spores of the Orange Tuft as seen through a microscope.

      Undersurface view of the pores of the Pine Bolete (see page 43).

      Undersurface of the Maze Gill, Daedalea quercina, a thick cork-like bracket fungus found on oaks.

Collecting mushrooms

      Mushroom distribution in southern Africa

      Fungi need moisture and suitable organic food sources to flourish. Habitat type, rainfall levels and seasons thus determine where different fungi occur. Some grow in grass, others on wood, a few on termite mounds and many only grow close to certain trees. In southern Africa, the majority of wild mushrooms, as well as other fungi, are confined to the wetter central, southern and eastern regions. Mushrooms often appear a day or two after rain, and the first rains of the season usually produce the most abundant and varied crop.

      • Before picking any mushrooms, learn the features of the poisonous ones, particularly the Amanita species (see pages 12–16).

      • When you first start to pick mushrooms, collect with an experienced mushroom hunter or consult an expert. • Pick only whole, fresh, healthy specimens and store each species separately. • Always record where each mushroom occurred.

      • Carry your mushrooms in a flat container or basket. • Only eat mushrooms that are typical of their species. • Mushrooms can be dried in an oven or on a well-aired rack.

Poisonous or edible mushrooms

      Most mushrooms are inedible. Extreme caution should be exercised before eating any mushroom. If a mushroom does not comply with all the features described it should not be eaten. Within this book, where appropriate, the edibility or toxicity of a mushroom is indicated by the symbol at the top of the page. For edible species, simple recipes are suggested where appropriate. For poisonous species the type of poisoning and symptoms are given.

      Types of mushroom poisoning

      1. Degeneration of internal organs, the liver and kidneys

      The Death Cap is the cause of 90% of all mushroom fatalities and takes 6–30 hours to act.

      2. Harm to the nervous system

      a) Muscimol toxins found in the Fly Agaric, Panther Cap, Inocybe, Panaeolus and Clitocybe act