Fly agaric mushroom: Beware of these highly potent and potentially deadly mushrooms in Yorkshire's woods

It wasn’t just thought up by the brilliant poet, Clement C Moore, who wrote so powerfully about Dasher and Prancer following Rudolf’s bright red nose. The idea has been around a lot longer than that.

Indeed, it is entirely possible that it goes back deep into the past and is actually the product of some pretty dodgy uses of an hallucinogenic mushroom in the depths of the Siberian birch forests.

Ask a child to draw a mushroom and there is a fair chance that they will colour it red and give it white spots because that is what is illustrated in so many children’s story books.

In reality the fly agaric that the gnome sits upon as it fishes for its supper in so many garden ponds is not remotely cuddly. It is potentially deadly and highly potent.

So, of course, is alcohol and that has never prevented large numbers of people putting themselves at risk in order to get into the Christmas spirit. Stuck in the cold out in northern Russia fermentation isn’t always easy. Nor is carrying around large quantities of liquid if you are nomadically following herds of reindeer.

It proved rather easier to get high by carrying around a supply of dried fly agaric mushrooms and extensive experimentation taught traditional communities a great deal of knowledge about the dose.

Without that extensive knowledge only a fool would play around with them, but it is widely reported that herding communities consumed the distinctive bright red mushrooms that grow so readily in birch forests.

Shamans who claimed to act as intermediaries between the spirit world and our own may have been particularly prone to taking significant quantities.

The way most shamans get into a trance like state is by hours of rhythmic drumming and chanting that are not dissimilar to the methods used by whirling dervishes.

Push the body hard enough for long enough and the mind seems to transport itself out of the body. Intensive visions result. The soul seems to fly.

An alternative way to get much the same effect without years of training is to down enough mushrooms to produce equally lively images. Which, of course, like all hallucinogenic drugs carries a significant risk of burning out large numbers of brain cells and leaving you struggling to distinguish reality from visions.

If you are stuck in the depths of a birch forest, there aren’t a lot of things to have visions about.

Most of your time is spent following reindeer from place to place and trying to make sure they don’t get lost. If you are going to dream about the things you have seen in the day and you are on a drug that inspires visions of flying then it is highly likely that when you sober up you are going to tell tales of flying reindeers.

I thought of this quite often this autumn. There is a wood near me where the fly agarics proliferate. At first all I could see was a couple of small caps pushing up from beneath the ground, but as autumn progressed there were thousands of them.

They tend to come in clumps of four or five together and as the cap expands and spreads out it can reach almost dinner plate size.

This is of course simply the fruiting body of a giant network of mushroom threads living beneath the ground and exchanging nutrients with the birch trees.

Billions of spores will be released from beneath each specimen and only a tiny fraction of these will ever find a new wood to colonise.

The huge caps start to look decidedly tatty as they get larger.

They get attacked by predators. Whenever there is a source of food on this scale something is going to want to eat it. In this case it is often flies. They target the older mushrooms and, if the fungus couldn’t protect itself it would be gobbled up in no time.

The toxins it produces are therefore almost certainly not primarily intended to have an impact on humans. They are there to ward off the flies. Stopping us is a bonus.

But if you have evolved an effective protection, it is a good idea to advertise the fact. It doesn’t help an individual creature if it gets eaten and its predator subsequently dies horribly with no known antidote. That is the reason for the bright red colour that children find so attractive. We are being warned to leave it alone.

Sometimes it is wise to take nature’s warnings seriously. I will leave the agarics to the intoxicated flies and stick to re-reading the poem whilst sipping a warm toddy.