What’s affecting some of our trees?
Our trees are facing a few naturally occurring diseases that live in the soil and timber. While they sound complex, they can be understood in a simple way:
See full factsheet here: Phytophthora Armillaria Ganoderma Fact Sheet
Phytophthora Dieback (a soil-borne plant disease)
What it is:
A microscopic organism in the soil that attacks plant roots. Once a plant is infected, it cannot recover. Think of it as a “root rot disease” that travels in wet soil and stops plants from taking up water and nutrients.
How it spreads:
- Moves naturally through water and soil
- Can spread quickly when soil is moved on boots, tyres, tools or machinery
Why it matters:
It can quietly spread through bushland and gardens, affecting many native plants and trees.
Armillaria Root Rot (a native fungus)
What it is:
A naturally occurring fungus in Australia that attacks tree roots and causes them to decay. This disease works slowly underground, weakening a tree’s roots until it can no longer survive.
What you might notice:
- Trees slowly declining over time
- Yellowing leaves
- Reduced growth
- Eventual tree death
Why it matters:
It affects a wide range of trees, both native and introduced, and there is no cure once a tree is infected.
Ganoderma (butt rot fungus)
What it is:
A fungus that breaks down wood inside a tree, especially at the base of the trunk. It’s like internal decay in the tree trunk, often hidden until you see the distinctive fungi on the outside.
What you might notice:
- Large, hard “shelf” or bracket fungi growing at the base of a tree
- These can grow quite big and stay on the tree for years
Why it matters:
While it plays a natural role in breaking down dead wood, it can also weaken living trees, making them unsafe.