You know that famous Keats line about autumn being the “season of mists and mellow fruitfulness”? Well, it’s also the season where all sorts of weird, wonderful, and often toxic fungi start popping up. (Or in the case of pricey truffles, staying teasingly hidden underground!)

Usually around this time of year, we get one or two fly agaric mushrooms popping up on our front lawn. But this year, we got a bumper crop of about thirty of them. Here’s a picture of just one little group with their distinctive white spotted red caps.

They’re the classic “magic mushrooms”, but they aren’t native to Australia. It’s thought they hitched a ride here on tree seedlings from the Northern Hemisphere. You won’t find them near eucalypts, though—ours always set up camp right next to our silver birch trees. Apparently, the two have a bit of a symbiotic relationship going on.

Now, a quick disclaimer: they’re pretty toxic if you eat them, though actual fatalities are rare. Historically, shamans would dry them out and powder them to use as powerful hallucinogens in their rituals. This has led to some interesting folklore. There’s even a (mostly debunked) theory that people under the influence saw reindeer flying, which is supposedly where Prancer and friends pulling Santa’s sleigh came from. In fact a lot of the folklore seems to come from Sweden, Finland and Russia – countries with vast expanses of birch trees.

And, if you’ve ever seen a garden gnome sitting next to a red-and-white spotted mushroom, you’re looking at a fly agaric. In folklore, gnomes are the guardians of the earth, while the mushrooms represent a mix of magic and danger.

But my favourite piece of trivia has to do with Alice in Wonderland. Remember when the Caterpillar tells Alice that eating one side of the mushroom will make her grow, and the other side will make her shrink? As it turns out, ingesting fly agaric doesn’t just cause hallucinations—it specifically warps your perception of size. That explains quite a lot about how Alice managed to fit down the rabbit hole and managed to talk to all manner of strange characters. Some people swear Lewis Carroll must have experimented with them himself. Others are more sceptical, arguing there’s no proof he took drugs. Then again, he was an Anglican deacon, so it’s not like he was going to brag about it in the church newsletter.

Even pop culture loves them. In the Super Mario Bros. games, Mario doubles in size to become “Super Mario” after eating—you guessed it—a fly agaric mushroom.

And as for the name “fly agaric”? It’s actually rather literal. In the past, people used to crush them up and use them as a pesticide to kill flies!