Hello again! 

Bit of a functional blog post, this one. You may have noticed that we’ve stopped selling Pleurotus citrinopileatus, commonly known as yellow or golden oyster mushrooms. There’s a good reason for it, and it’s not availability; it’s quite the opposite in fact!

It appears (and this might change, but we can’t really see how) that this particular mushroom is really good at filling its evolutionary niche. Too good, in fact. So here’s what appears to have happened:

Golden Oysters are native over in Asia, but are now popping up all over the place in America, and have been found in four locations in the UK as of 2025. This is a bit of a problem, as over in America, they’re outcompeting the native fungi. 

The first sighting in the UK in the group Mushroom Spotters UK 

They’re really easy to grow, and they’re tasty, so what’s most likely happened is that people have bought a grow kit, and then when they’d harvested what they wanted, they chucked the block out into the rubbish, or the garden, or the bin where they just take all your rubbish to somewhere else and dump it.

Photo: Source

The mushrooms have then carried on growing (they’re very resilient, like all oyster mushrooms), have sporulated, and then started growing in the wild. It may sound a bit “one in a million”, but all it takes is one in a million to start gaining a foothold, and there’s been a heck of a lot of golden oyster kits and liquid culture sold all across the world (including by us). 

There’s obvious historical precedents for this sort of thing, most notably in Australia, where England sent across all the people we decided were guilty of crimes, and they treated the indigenous population like shit and still do to this day, or in America where blimey the same thing happened? Man, we fuckin’ suck as a species, and should do better. 

You thought we were going to mention the rabbits and toads thing in Australia, didn’t you? Well just in case you weren’t aware of it, back in 1859 some rich dude introduced a grand total of 24 rabbits to Australia so that he could breed them and do a bit of hunting, for fun, because again, we fuckin’ suck as a species and should do better. The rabbits then started reproducing like, well, rabbits, and by 1866 the local newspaper reported that hunters had killed 50,000 of them that year. They’d become an invasive species, and had been introduced to an ecology that just wasn’t able to manage their growth properly. It was warm enough for them to breed all year round, there was plenty of food, and not anywhere near enough natural predators, which means they just fucked everything up. Not their fault really, is it? We then developed increasingly more fucked-up ways to try and manage our mistake, which I’m not going to get into because they’re all horrible, but a special mention goes to the people that created viruses that make rabbits insides melt because Jesus fuckin’ Christ dudes you’re like the bad guys in a horror film. 

Then in 1935 some absolute brain genius who clearly had not been paying attention to anything outside of his head decided that the best way to control the native cane beetle was to introduce some cane toads. “Probably nothing will go wrong here, yeah lads? Never seen anything go wrong when we’ve done this before yeah? You sure? Ah cool yeah I’m sure too let’s go eat some more lead sandwiches.”

Things went wrong. How strange!

In March 1937 you’ve got 62,000 toadlets (cool name), in 2011 you’ve got about 200,000,000. Much like the rabbits, there weren’t enough pre-existing environmental controls to stop their spread. Their skin and glands are toxic, so they just fuck up most things that try to eat them, and the toads will eat pretty much anything that fits into their mouths. Probably could’ve read about that before introducing them to be honest. 

Do you see where we’re going here? Pleurotus citrinopileatus is way too good at what it does for the new environments it’s been introduced into, just like the rabbits and the toads. It’s like putting Brock Lesnar into a kid’s karate class and letting him go hog wild on them - after a while you’re just going to have a room with Brock stood in it, covered in blood. Trees that are colonised by golden oysters have around 50% less other fungi growing in them as they just get outcompeted quickly. Golden oysters are saprotrophic (wood loving), and they’re better at it then anything else, so not only do they take the food and the space before other saprotrophic fungi can access it, they also break the trees down quicker which means that native fauna, such as woodpeckers, have less places to use as a habitat.

This is obviously the tip of the iceberg, but that’s why we’ve made the decision to stop selling it. We know that no-one means to spread it outside on purpose, but much like the new Alien series at some point all the careful containment in the world will fail, and that’s all it takes to compromise the delicate ecosystems we’ve got in the UK even further. We love going out and finding mushrooms, but we love going out and finding different types of mushrooms, and maybe that won’t happen as often if we don’t act to stop the spread. 

No shade intended on any other vendors who choose to keep selling golden oyster kits and liquid cultures, we’ve all got our own different moral codes, but it’s not something we feel able to do in good conscience any more. If you’re still hankering for some oyster mushrooms, we’d happily suggest others or even if you’re trying to avoid the whole spore thing altogether, sporeless blue-grey oysters!

We are currently in talks with Natural England and also supporting efforts of researchers in the USA to understand the effect of this species and will share any new info when we have it - keep your eyes peeled!

Here's the study if you'd like to take a look yourself:

Invasive golden oyster mushrooms are disrupting native fungal communities as they spread throughout North America