There’s a hidden world beneath our feet. In the darkness, away from the light, down in among the tree roots, lies an invisible network that is vital to the health of our woodlands and even our planet. Yes, folks, it’s the fantastic and often bizarre world of fungi…or ‘mushrooms’ or ‘toadstools’ if you prefer. This is their time of year, with strangely-shaped and colourful fungi popping up all over the place.
Tawny grisette, Amanita fulva
There are lots of myths surrounding fungi. One is that they’re all poisonous. They’re not – some are actually very good to eat – but you do need to know what you’re doing with them. There aren’t actually all that many that will kill you outright (though some will do it slowly by knackering your kidneys) but if you don’t know what it is, the golden rule is don’t eat it. Equally, don’t destroy it – it depresses me to see children being told to ‘kick over toadstools because they’re dangerous’. They’re only dangerous if you eat them so any danger is largely self-inflicted!
Cortinarius mushroom, showing “cortina” – the web-like structure under the cap
Another myth is that ‘fungi kill trees’. Again, some do…but it’s only a tiny minority (like honey fungus) that are deadly to healthy trees. Most of the fungi we see on trees or dead wood are actually ‘saprophytes’ – dead wood decomposers. They don’t kill the tree but are breaking down the dead wood or leaves. It’s hard to over-emphasise how important this role is in our woodland ecosystem. Without fungi, we’d be up to our eyes in fallen leaves and dead trees …but, instead, they help rot all the organic matter and release nutrients back into to soil…which the trees and plants then use to grow. Fungi are a vital part of the nutrient cycle in any woodland.
I often think that the really impressive thing about fungi is the most well-hidden. When we think of fungi, we think of a ‘mushroom’ – the field mushroom-types we buy in shops or a red-and-white spotty thing in a children’s book. But that’s not really what fungi are all about; that’s just the showy public face, all the real business goes on, quietly and invisibly underground. Most fungi, unless they have a pressing reason to do otherwise, exist solely underground, as a network of ‘mycelia’ -a mass of fine, thread-like ‘hypahe’ (a bit like roots but a fraction of a millimetre across). Thus picture is unfortunately the best illustration of a mycellium I have. I say ‘unfortunately, as it’s actually growing on dog poo (I once was presented with a mould-cover dog poo by a child on a school visit ‘ What’s this?’ ‘Put it down RIGHT AWAY and go and wash your hands….’)
Phycomyces (pin mould) on dog poo
Often only when fungi get stressed (eg by drought) or can’t spread any further will the fungus actually produce a mushroom. This is its survival strategy. The mushroom will release spores, which will blow away and land elsewhere, allowing the fungus to survive or spread. That’s why you so often find fungi on track edges – they can’t make their way through the compacted soil under the track – so up pops a mushroom to allow it to keep going.
A huge number of fungi are actually in a symbiotic (mutually beneficial) relationship with the trees. Their hyphae wrap around the tree roots and exchange water and nutrients with them. The fungi gets sugars from the tree’s photosynthesis (which the fungi can’t make for itself) and, in return, helps the tree absorb water and nutrients from the soil. And (this is the really good bit) any one tree may have a relationship with half a dozen different fungi. Those fungi, in return, may be in a relationship with half a dozen different trees…and on it goes. Fungi effectively join most woodlands into one huge ‘super-organism’ – all connected invisibly by magical mycelia.
The spore-bearing ‘teeth’ of the scaly tooth fungus
Okay, that’s enough of the science bit. Let’s have a look at some of the fungi that are up just now and we can see!
Let’s start with the first fungus may of us ever see, probably in a nursery rhyme book. Here’s the fly agaric. Don’t eat it. The name comes from the fact it was crushed into saucers of milk to kill flies.
And, right down the other end of the scale – the chanterelle – a very popular eating mushroom. If you ever do pick mushrooms, it’s good practice to seek the landowner’s permission and never pick more than 10% of the fungi in any area.
Another highly-prized one is the cep. Dried and sold as porcini, this is a member of the bolete family which have pores (like a sponge) under the cap. A lot of brown birch boletes resemble cep but aren’t. They generally have the advantage that they won’t kill you if you get it wrong, but some will make you very familiar with the back of the bathroom door and those immortal words ‘Armitage Shanks’.
Some of the most colourful fungi are the russulas, or brittle-gill family. They are often quite difficult to tell apart and come in every colour, from red to green to yellow.
A red Russula or brittlegill mushroom. These mushrooms can be hard to tell apart.
Yellow russula or yellow brittlegill
Grass green russula
Fungi also come in all sorts of weird shapes and sizes. Puffballs are ‘gastromycetes’ (stomach-shaped fungi) and their spores were used to help clot wounds. Some can be used as tinder to light fires, too.
The tiny, talon-shaped ergot is easily overlooked but can be dangerous in cereal crops. They grow on grass heads and have unpleasantly hallucinogenic properties, as well as causing convulsions and abortion in livestock. Look at, go ‘hmmm, ergot’ to yourself, then walk away.
Ergot in timothy grass – one of our more toxic species
And we’ll finish off with the fungus which, for some reason, causes the most hilarity. The stinkhorn, or, to give it its scientific name Phallus impudicus . Finding this on a fungi walk always results in a bit of sniggering – can’t think why. It gets its common name from the fact it does stink (to me, it smells a bit like gas, that’s oven gas, not any other sort) to attract flies to the mass of spores on the tip. They crawl all over the greenish, slimy spores, which stick to them, then they fly off and spread them elsewhere. They were also eaten as an aphrodisiac, an act which owes more to optimism than good sense. Another fungus which is best admired (if that’s the right word) from a distance!