Nature on our Doorsteps: Bracket Fungi

Rosaleen Dwyer is the County Heritage Officer at South Dublin County Council – every week she gives us an insight into nature on our doorsteps and the beautiful biodiversity of its plants and wildlife.

Bracket Fungi can sometimes be seen on the trunks or branches of trees.  Their name comes from their shape, which is like the wooden or metal bracket that supports a shelf.

There are many different species of Bracket Fungi.  They all act to break down wood, helping to recycle dead wood back into the soil.  Some of these fungi, however, can also infect living trees and can cause them to die.

Bracket Fungi have the ability to break down the very tough compound in wood that gives trees their strength.

This compound is called lignin.  It occurs in the cells of trees and other woody shrubs, and it gives strength and rigidity to plants.  Lignin does not rot away quickly, but bracket fungi can easily break it down.

Scientists have suggested that there may be a connection between these lignin-eating fungi and the formation of coal.

Coal is formed from plants and trees that grew in ancient forests that died and fell, millions of years ago.

As the earth evolved, geological processes caused the deep layers of organic matter in these forests to be covered by new soils and rock formations.  Over time, the layers of organic matter were compacted into solid coal.

Bracket fungi are shaped like a bracket that holds up a shelf

The main period of coal formation was between 170 and 300 million years ago.  Scientists have discovered, however, that Bracket Fungi evolved around 290 million years ago, towards the end of the major coal-forming period.

These scientists suggest that the newly evolved Bracket Fungi spread far and wide, breaking down the tough lignin in the wood and recycling the trees back into the soil.

This helped to reduce the volume of organic material on the surface of the earth that might otherwise have been formed into coal.

Other scientists, however, suggest it was natural changes in climate and geological processes that slowly changed the conditions needed for coal to form.

Nonetheless, the coincidence of the arrival of lignin-eating fungi and the end of coal formation is an interesting one.