Fungi play vital role – but can be deadly, warns Sheffield wildlife expert

I have already seen many different species in woodlands and grasslands, and especially on

roadside verges with trees.

Many fungi are associated closely with plant roots and particularly with trees, and these are known as mycorrhizas.

Generally unseen unless to examine the roots closely and know what to look for, the fungi really make the natural world go round.

They breakdown dead organic matter and provide the resulting nutrients to higher plants such as trees and in some cases herbaceous flowers in exchange for sugars manufactured in the plant cells from the energy of sunlight.

Such associations are known as symbiosis or mutualism and without the fungi none of this would happen and very little organic materials would decompose.

Other fungi, of course, are aggressive diseases and cause many of the tree deaths we are seeing at present.

Amazingly within healthy trees for example, there are a whole set of ‘good’ fungi which defend the tree against invasive by pathogens which cause or diseases.

Yet almost none of this is visible to us, and the activities of this ‘invisible biodiversity’ goes on constantly, but unnoticed.

Only when things go wrong are the fungi obvious and apparent.

The other time when larger fungi become obvious is when they ‘fruit’ to produce the familiar mushrooms.

These are merely the fruiting bodies which produce myriad reproductive spores to spread the fungus to new places, partners, or hosts.

And, of course, many of these mushrooms, like the one in my photograph, are edible and delicious; but others are distasteful and in quite a few cases, can be deadly poisonous. Basically, if you don’t know, are not expert, or are unsure about a mushroom then leave it alone and certainly don’t eat it.

The picture shows common parasol mushroom which tends to be found in areas of unimproved grassland and opens up to be a parasol-like cap about five inches across.

These are both beautiful and good to eat, but similar species are deadly poisonous.

Prof Ian D Rotherham, of Sheffield Hallam University, is a researcher, writer and broadcaster on wildlife and environmental issues.