On the Wild Side with Professor Ian Rotherham: Fungus season is upon us

With wet weather and falling temperatures, this is the season of the mushrooms. I spotted this fungus or mushroom in Lady Grove Wood high above Darley Dale in North Derbyshire. Known as the Spindleshank (one of the ‘toughshanks’) or scientifically, Collybia fusipes, it is a parasitic fungus growing on the basal roots of deciduous trees such as oak.

Identification was by my friend Dr Paul Ardron. The actual ‘mushroom’ is merely the fruiting body of the fungus the hyphae of which are inside the wood of the roots and breaking them down, and in effect this is akin to the flower of a flowering plant. Underneath the cap of this mushroom, the gills bearing the reproductive spores, are distinctively widely spaced.

This parasite potentially causes rot of the roots of deciduous trees, especially oaks and beeches, both of which are in this woodland, and may cause dieback of the tree crown. Occasionally they also attack coniferous trees. The spindles (with the stems swollen but then tapering sharply towards the base) and which give the fungus its common name, are generally hidden under soil and root-wood.

The young mushrooms as they emerge look rather like a mass of copper nails. Mushroom enthusiasts are frequently interested in finding and eating them (which can be a risky business) and whilst the Spindleshank is noted in guidebooks as ‘edible’ it is also described as ‘not worthwhile’ on account of its toughness. 

The business end of the mushroom is in the masses of tiny hyphae that often go unseen either as pathogens or parasites, as symbiotic partners with plants, or as saprophytic organisms living off and breaking down dead organic materials. These are neither plants nor animals but are a separate kingdom of the fungi and are probably more closely related to animals than to plants.

Although many fungi go unseen about their business, these organisms help power the growth of great trees through their symbiotic associations with tree roots in what are called ‘mycorrhizas’. Other types of fungus even grow inside healthy trees to help ward off diseases. 

Professor Ian D. Rotherham, researcher, writer & broadcaster on wildlife & environmental issues, is contactable on [email protected]; follow Ian’s blog (https://ianswalkonthewildside.wordpress.com/) and Twitter @IanThewildside