Talk: 28 November 2017 Fungi in the New Forest

Sara Cadbury captivated the audience with her talk on New Forest fungi. Sara, an expert mycologist and member of our own Naturalist Society started with the identification of fungi including the difficulties that this involves due to mycology being a rapidly advancing science, hence the names in the identification books are often out of date. Identification is a calculated guess without the use of a microscope. Identification is based on habitat ( both woodland/grassland, also which tree /plant it is attached to ) ; size; colour ( also difficult as some colours are water soluble); colour of spores, smell and if it has a cap or gills. Sara showed us the cocoa coloured spores of the large Ganoderma fungi found in the forest.

Broadly fungi can be divided into two groups- Basidiomycetes, which drop their spores, examples being Boletus fungi, and Ascomycetes, which shoot their spores out, examples being cup fungus and green oak cup.

Sara had photographs of spores, showing the variation in size, shape, ornamentation and spikes and the means of measuring these microscopic spores. The microscope also revealed the structure, named a basidium, of the Basidiomycetes, which have usually four arms at the apex, each of these arms has a spore attached. These spores are immature, and for identification purposes cannot be measured until unattached. In the Ascomycetes the spores are in asci, and when ripe they shoot out of the top.
Next we looked at Ergot, which occurs mainly on cereal crops, usually rye. These fungi used to cause death, as the fungi were incorporated into flour and then onto bread. The poison within the Ergot caused constriction of capillaries, leading to gangrene and death. The symptoms involved itching of the extremities and hence the disease was named St Vitus dance.

A spalted bowl
Sara bought along many examples of spalted wood, which is greatly favoured by wood turners, due to the black lines that are so decorative in the finished bowls. These black lines are war zones where two fungi, of either similar or different kinds are defending their territory. Between these two lines there is often a further fungus growing. The Porcelain Fungus can produce a yellow line in these circumstances.

Sara then spoke of a number of different and interesting fungi to be seen in the forest. Stinkhorn has an unusual spore dispersal as the smell it emits attracts beetles and flies, which the disperse the spores. Usually spores are wind dispersed.

Devil's Fingers
Forest specialities include Clathrus archeri, Devils Fingers, which occur on Setley Plain, their spore dispersal is also by flies and beetles. Poronia punctate, Nail Fungus, occurs on manure from New Forest ponies that have poor nutrition and diets high in roughage. Hericium erinaceus, Bearded Tooth, Hericium caralloides , Coral Tooth and Hericium cirrhatum, Tiered Tooth, are all rare but do occur on beech trees in the forest.

Sara explained that the large diversity of fungi in the New Forest is due to the variety of habitats, from the Headon beds south of the A31 to the sands and gravels in the north.
Sara was particularly interested in the numbers of fungi with parasites themselves- showing us photographs of Peppery Boletus fungi being parasitic to Fly Agaric. Earth balls and puff balls also have parasites. We finished with photographs of Chicken in the Woods, Dyers Mazegill, Magpie Fungus, wax caps and Wood Blewit.

Sara was warmly thanked by a full audience of members and visitors. Visitors are very welcome at both the evening meetings and our walks throughout the year. Details to be found on our website