The Kingdom of Fungi 

This is the time of year when most mushrooms can be spotted, and although they've been a staple in our lives for thousands of years, they were often just lumped in with the plant kingdom, appreciated for the culinary or medicinal benefits, but not much more.  

It wasn't until 1969 when American ecologist Robert Whittaker recognised them as their own separate biological kingdom (or queendom!) and scientists really began researching the vital role they play in our ecosystems. 

Fast forward to 2026, and we are truly in a mushroom boom. Lion's Mane and king oyster is appearing on supermarket shelves, cordyceps and reishi in our pharmacies, and many scientists are now studying fungi's ability to solve issues like oil spills and food security challenges. 

It's an exciting time to be interested in fungi. 

The Hidden Life of Mycelium

To fully appreciate fungi, we first have to understand that the part of it that we see, ie; the mushroom, is just the fruiting body of the larger fungal organism. The rest is mycelium – thread-like roots that spread out through soil, wood, and sometimes insects! 

When conditions are right, which is usually autumn in this part of the world, the mycelium pushes up mushrooms to spread spores into the air and grow new fungi. If you want to see mycelium, look out for rotting wood on the forest floor and you may see a white webbing spreading over and through it. This is the body of fungi! 

Fungi and trees: a lifelong partnership 

It's with this mycelium where the magic truly happens, and where the important connection to trees comes into play. 

Fungi can be put into four different categories; saprotrophic, mycorrhizal, parasitic, and endophytic. We'll focus on the first two, though for any Last of Us fans, you may want to research into parasitic! 

Saprotrophic mushrooms are the reason we aren't surrounded in decaying wood, old plant matter and dead animals. They are the decomposers of the plant world. If something has died, they're consuming it.  

Some of the tastiest mushrooms are decomposers, such as shiitake and oyster. A dying or fallen tree becomes host to this type of fungi, which in turn feed other critters – not just us! You can read more about the importance of fallen trees in our other story. 

Mycorrhizal fungi have a fascinating relationship with trees and other plants. Over 90% of plants are dependent on mycorrhizal symbiosis. The mycelium brings in added moisture and nutrients to the plant, and in return, the plant gifts them access to sugars. This allows the plant to grow faster and stronger. Many farmers and gardeners will put mycorrhizal fungi in the soil to encourage better growth. In fact, our Urban Forest team are exploring this idea for growing more climate resilient trees. 

Truffles, porcini and chanterelles are all mycorrhizal and are a sign of a healthy ecosystem. Undoubtedly the most notable mushroom, the fly agaric, is mycorrhizal, and forms a relationship with the roots of trees suck as oak, pine and birch. 

We said we won't dive into parasitic mushrooms, but it is worth noting that every fungi has its purpose, even the ones that are killing trees. Chicken-of-the-woods, a mushroom favoured by foragers for its meaty texture, will infect living trees, and eventually kill it. But while it does so (and this can even take decades), its breaking down the tough wood for other creatures to benefit from, such as bats and beetles. 

How can we help fungi? 

Just like all parts of our ecosystem, fungi must be protected. But also like many parts of our ecosystems, this kingdom under threat, mainly from habitat loss, agricultural pollution and illegal commercial foraging.  

There are some easy actions you can take to help support fungi: 

• Leave dead wood and autumn leaves 

Both of these are food for fungi, and if you're able to, leaving them where they are is a great way to not only support the fungi kingdom, but in return will make your soil much healthier. 

• Minimise soil disturbance 

Trial the no dig method and give the mycelium in your soil a chance to grow strong and form connections with the plants in your garden.  

• Reduce chemical use 

Overuse of fungicides and some other chemicals can harm beneficial fungi as well as the target organisms. Promoting healthy soils often supports fungal diversity. 

• Forage responsibly 

Enjoying wild mushrooms can help people connect with nature (never pick or eat a mushroom unless you're completely confident in its identification) but it's important to forage responsibly. Take only what you need and leave some mushrooms behind so they can release spores. Check the rules of the area you're in before picking. If you're in a nature reserve, conservation area or other protected site, best to take only photographs. Consider growing gourmet mushrooms at home – it's easier than you think! 

• Get a little wild 

The corner of your garden, a section of our parks and greenspaces – let's leave nature do its thing undisrupted. You'll be amazed at what can appear!

Interested to learn more about our fungi friends? 

Here are some ideas to explore the magical world of mushrooms: 

• Whilst on nature walks this autumn, cast your eyes to the ground and see what mushroomy surprises await! Use apps like iNaturalist to help identify species, submit your sightings, and contribute valuable records that support our understanding of fungal diversity. 
• Join a guided fungi walk with a local wildlife group, nature reserve or mycological society. 
• Follow professional and budding mycologists on social media. We especially enjoy the amazing photography and time lapse films! 
• Check out fantastic documentaries like Kingdom Fungi, which follows amateur and professional mycologists across England as they document, study and protect the fascinating world of fungi, or Fungi: The Web of Life, available on the BBC and staring biologist and writer Merlin Sheldrake.

Happy mushroom spotting, see you on the woodland floor! 🍄‍🟫