One thing binds gardens together more than anything else. Fungi.
You find fungi in Antarctica and in nuclear reactors, they
were here before us and will be here long after we’re gone. They live inside
your lungs, your skin is covered with them and can be found in hair as they are
the primary cause of dandruff. Fungi are the most under appreciated organisms,
yet they could cure you from smallpox and turn cardboard boxes into forests.
There are vastly more fungi species than plants and each and every one of them
plays a crucial role in life’s support systems.
It’s no wonder “No dig gardening” is beneficial to the soil
when you see how the soil web holds together.
Mycology is the study of fungi and it’s found that this important
organism on the planet is around 1 billion years old. They are one of the oldest things on earth.
They have their own category as they are neither animal nor
plant in biology terms and there are millions of species.
Mushrooms are the fruiting bodies of the fungi, far more
goes on underground. They are microscopic themselves but can cover massive
areas covering hundreds of acres.
The term fungus can evoke negative connotations as we
associate the word with itchy toes and other skin or body irritations and
diseases. However they are very much a force for good, we just don’t notice it.
Life as we know it wouldn’t be possible if it wasn’t for fungi.
Let’s go back a few billion years.
Single celled organisms had been in the oceans for a long
time. The land was just a rocky mass with no life. Early bacteria developed the
ability to use the sun for photosynthesis, a process of converting the light
into nutrients.
The by-product of this is oxygen, which was released into
the atmosphere allowing for more complex life forms to form which we call the “Cambrian
Explosion”.
Sixty million years after that, more complex life forms came
onto land in the shape of fungi with their unique ability to break down and
digest rocks, turning it into soil. The
fungi secreted a digestive enzyme and along with mechanical pressure they were
able to access nutrients from the rock that were unavailable to any organism at
the time. Fungi also fed on the build-up of bacteria on the shore over the
millions of years when nothing else was on land.
What followed were small protoplants such as liverwort.
Fungi had minerals and the plants had photosynthesis and they both needed what
the other had to survive. Fungi and plants started to cooperate in a process
called symbiosis, which is a mutually beneficial relationship.
Plants spread and the world started to turn green. Some
plants became independent of the fungi and a new balance was created. More
oxygen was produced and as things died they needed to be recycled so they could
continue to be used. This is where fungi come in. They eat death. By breaking
down dead things they allow nutrients to be reused which is fundamental for
life on earth.
This symbiosis is alive and well in the form of Mycorrhiza which
continues to change and evolve and benefits up to 90% of plant growth in the
world.
Some plants such as the orchid still rely on fungi for its
survival. The plant has virtually no independent energy reserve in its
germination stage. Orchids can be parasitic though and instead of cohabiting
with the fungi, the plant sucks the energy from it. The fungus itself will be
in a symbiotic relationship with another plant and will use that energy to feed
the orchid, an indirect photosynthesis source. A fungus can also be a parasite
too as we are aware in the garden and it’s not very palatable when you realise
you have just put a mouldy strawberry in your mouth
Fungi can help exchange nutrients amongst trees, if a tree
is being shaded by other larger trees it can be fed more nutrients via the
fungi so it grows tall enough to survive. These common mycorrrhizal networks
are everywhere in our gardens and even connecting huge forests. It could be
known as “Natures Internet” or even the “Wood Wide Web”
Signals in plants connecting in this way can warn of
oncoming danger in the form of pests and disease. They can help to pass on
chemicals to deter or hinder the growth of competing plants by depriving them
of nutrients. The fungi can also pass on chemicals to stop pests eating leaves.
It’s in the best interest of the fungi that the plant survives
which allows for the continuation of their symbiotic relationship.
Fungi isn’t always visible but it a cornerstone of our
ecosystem, forging relationships with other organisms – both alive and dead.
It’s not just plants that interact with fungi either. It’s a
food source for us, the yeast we need for our bread, medicines, pest control,
leather substitute and packaging.
Fungi are cool, I’ve only skimmed the surface of this
complex world but it’s all around you in the garden.
