The fungi beneath your feet

As winter sets in you may start to see the emergence of fungi on your land. This shows us it is the indigenous season of Tunna, which typically occurs between May and August here on lutruwita (Tasmania). These fungi can take many strange and unusual forms, including the classical mushroom, brackets, jellies, corals, birds’ nest fungi, stinkhorns, clubs, rusts, boletes, and toothed fungi. There are also many species that have fruitbodies too small to see with the naked eye, that we are only just discovering with the advent of new high-throughput DNA sequencing technology. This technology is doing what the microscope has done for other biological disciplines in terms of expanding our knowledge of the Kingdom fungi.

Fungi occur in every habitat on earth, including terrestrial, marine, and aquatic environments; as symbionts on our skin; and within our digestive system. Scientists estimate that there are around 17 species of fungi for every plant species.

These often brightly coloured yet cryptic structures are the sexual reproductive structures of the fungus, whose body comprises fine networks of hyphae known as mycelium. These hyphae are typically 10 micrometres (10/1000ths of a millimetre) wide and are made of organic polymers, typically chitin, which is the same substance that makes up the exoskeletons of insects and crustaceans. One handful of soil can contain as much as 50 km of fungal hyphae.

These mycelial networks can be quite small, around 5 cm diameter in some species such as Laccaria, to many hundreds of square metres in species such as Russula. You can think about the differences between these fungi as analogous to a small herb, or an old-growth Eucalyptus regnans (swamp gum/mountain ash) tree. You will often see Laccaria, recognisable by their flesh-coloured gills under chestnut brown caps, growing along the edge of tracks and in disturbed places such as new plantations. Areas that have abundant fruit bodies of Russula tend to be older systems, with less recent disturbance, such as old-growth forests.

These larger fungi form huge networks, that connect many different species of plants together using relationships with plant roots known as mycorrhiza. These mycorrhizal connections enable the plants to exchange nutrients gathered from the soil by fungi, such as calcium, phosphorus, and nitrogen, with sugar that the plant makes through photosynthesis. These mycorrhizal relationships are present in 80% of the world’s plants and have been present since the earliest land plants evolved. Plants cannot survive without their fungal partners, and we should be viewing these systems not as individuals, but as meta-organisms, where fungi, bacteria, archaea and viroids all contribute to the function and survival of the association.

Mycorrhizal networks also enable plants to communicate with each other, as well as learn and respond to environmental stimuli as a group. Canadian mycologist (mushroom scientist) Suzanne Simard has found that 70% of the nitrogen that passes through the mycelial networks between trees is in the form of glycine and glutamate, which are the same neurotransmitters in our brains that we use to think. This discovery has caused us to question the way we think about cognition and sentience in the natural world.

If you want to know more about the fungi growing on your property, there are several great resources available that are good for beginners including:

• Field Guide to Tasmanian Fungi – Gates and Ratkowsky (available at fungimap or through the Tasmanian Field Naturalists)
• FungiFlip
• Fungimap website
• Fungimap Australia project on inaturalist – add your records to the Atlas of Living Australia and get community IDs on your photos.
• Tasmanian Fungi facebook page.

When taking photographs of fungi for identification there are some important points to remember:

• Take several angles, from the above, at a 45 degree angle, and from the side so the gills are clearly visible.
• Frame the photograph so the fungus occupies most of the photograph, and all the diagnostic features are visible, i.e. the cap, the gills and the stem in mushrooms.
• Use a coin or ruler for scale.
• Use a macro lens if you have access to one.
• Try and capture all the growth stages of the fungus, from buttons to mature.
• Use a small tripod, particularly in dark conditions, so your photos don’t come out blurry.

Things to take note of:

• What is the fungus growing on? E.g.: soil, live plant (list species if known), dead wood, another fungus, a dead insect.
• What sort of vegetation or habitat did you find the fungus in. List dominant species if you know them.

So next time you encounter a mushroom, a bracket, or a tiny cup fungus, remember there is far more going on than meets the eye. While we only witness their presence for a fleeting moment, increasing our understanding of their ecology, taxonomy, and how to address their conservation needs is essential if we are to look after our conservation estate and preserve biodiversity for future generations.

Originally published in The Running Postman