Tree Fungus in South East Queensland: Identification, Impact & Management

Trees are an integral part of South East Queensland’s vibrant ecosystems and urban landscapes. They provide shade, improve air quality, support wildlife, and enhance the aesthetic appeal of our surroundings. However, the health of these trees can be compromised by various factors, including fungal infections. Tree fungi can cause significant damage, affecting not only individual trees but also the broader environment and economy. Understanding how to identify, prevent, and manage tree fungi is essential for maintaining the health and beauty of our green spaces.

Common Tree Fungi in South East Queensland

Myrtle Rust (Austropuccinia psidii)

Affected Species: Members of the Myrtaceae family, including eucalyptus, bottlebrush, paperbark, and lilly pilly trees.

Symptoms:

Bright yellow or orange powdery spores on young leaves, shoots, and stems.
Deformation of leaves and shoots.
Dieback of twigs and branches.

Impact:

Severe defoliation and stunted growth.
Reduced flowering and fruiting.
In extreme cases, death of the tree.

Armillaria Root Rot (Armillaria spp.)

Affected Species: A wide range of native and exotic trees, including fruit trees and ornamentals.

Symptoms:

White, fan-shaped fungal growths under the bark.
Honey-coloured mushrooms at the base of the tree during wet conditions.
Wilting and yellowing of leaves.
Dieback of branches from the crown downward.

Impact:

Causes root rot, leading to structural weakness.
Can result in tree collapse, posing safety hazards.

Phytophthora Root Rot (Phytophthora cinnamomi)

Affected Species: Over 2,000 plant species, including many native trees and shrubs like banksias and grevilleas.

Symptoms:

Wilting foliage and leaf yellowing.
Darkened, rotten roots.
Reduced growth and eventual death.

Impact:

Destroys root systems, hindering water and nutrient absorption.
Significant threat to biodiversity in native forests.

Ganoderma Root and Butt Rot (Ganoderma spp.)

Affected Species: Various hardwood and softwood trees, including palms.

Symptoms:

Large, shelf-like brackets (conks) with a woody texture on the lower trunk or roots.
Decay of the heartwood leading to hollow trunks.
Reduced vigour and leaf size.

Impact:

Internal wood decay compromises structural integrity.
Increases risk of tree failure during storms or high winds.

Anthracnose (Colletotrichum spp.)

Affected Species: Deciduous and evergreen trees, including sycamores and ash trees.

Symptoms:

Dark, sunken lesions on leaves, stems, flowers, or fruits.
Premature leaf drop.
Twisted or deformed new growth.

Impact:

Reduces aesthetic value.
Weakens trees, making them more susceptible to other stresses.

Implementing these strategies helps maintain tree health and resilience during periods of extreme heat.

Powdery Mildew (Various species)

Affected Species: Many trees and shrubs, including oaks, maples, and crepe myrtles.

Symptoms:

White or grey powdery growth on leaves and stems.
Distorted or stunted leaf growth.
Premature leaf drop.

Impact:

Interferes with photosynthesis.
Can weaken young trees if infections are severe.

Implementing these strategies helps maintain tree health and resilience during periods of extreme heat.

Sooty Mould (Various species)

Affected Species: Trees infested with sap-sucking insects like aphids, scales, or mealybugs.

Symptoms:

Black, sooty coating on leaves and branches.
Sticky honeydew residue from insect excretions.

Impact:

Blocks sunlight, reducing photosynthesis.
Indicates an underlying pest problem that needs addressing.

Canker Diseases (Various fungi)

Affected Species: Many hardwood trees, including eucalypts and wattles.

Symptoms:

Sunken, dead areas on branches or trunk.
Oozing sap or resin from affected areas.
Dieback of branches beyond the canker.

Impact:

Can girdle branches or trunks, cutting off nutrient flow.
Leads to branch dieback or tree death if severe.

Bracket Fungi (Polypore species)

Affected Species: Dead or dying trees, both hardwoods and softwoods.

Symptoms:

Hard, shelf-like fruiting bodies on trunks or branches.
Discoloration or decay of wood internally.

Impact:

Indicates internal decay and compromised structural integrity.
Affected trees may become hazardous.

Implementing these strategies helps maintain tree health and resilience during periods of extreme heat.

Leaf Rust (Puccinia spp.)

Affected Species: Various trees, including wattles and eucalypts.

Symptoms:

Yellow, orange, or brown pustules on the underside of leaves.
Premature leaf drop.
Reduced vigour.

Impact:

Severe infections can lead to defoliation.
Affects overall tree health and growth.

Implementing these strategies helps maintain tree health and resilience during periods of extreme heat.

Identifying Tree Fungi

Visual Signs

Leaves: Look for discoloration, spots, lesions, or unusual growths on leaves. Yellowing, browning, or wilting can indicate fungal issues.
Bark and Trunk: Presence of mushrooms, conks, or fungal mats on the bark. Cracks, cankers, or oozing sap are also warning signs.
Branches: Dead or dying branches, especially if they exhibit sunken areas or fungal growths.
Roots: Mushrooms or fungal growth at the base of the tree can indicate root rot.

Environmental Indicators

Weather Conditions: Wet and humid conditions favour fungal development. Extended periods of rain or high humidity can increase the risk.
Soil Conditions: Poor drainage or compacted soil can contribute to root diseases.
Tree Stress: Trees weakened by drought, pests, or mechanical damage are more susceptible to fungal infections.

Regular inspections and being attentive to changes in your trees can help in early detection of fungal problems.

Impact of Fungal Infections

On Individual Trees

Health Decline: Fungi can interfere with a tree’s ability to transport water and nutrients, leading to reduced growth, leaf loss, and eventual death.
Structural Weakness: Decay-causing fungi compromise the strength of wood, increasing the risk of branch or whole-tree failure.
Reduced Aesthetic Value: Visible symptoms like leaf spots, cankers, and fungal fruiting bodies detract from the tree’s appearance.

On Surrounding Environment

Spread to Other Plants: Many fungi produce spores that can infect nearby trees and plants, leading to widespread issues.
Ecological Imbalance: Loss of trees affects wildlife habitat, soil stability, and local biodiversity.
Pest Attraction: Some fungi attract insects or rodents, which can further harm trees and spread diseases.

Economic Impact

Property Damage: Falling branches or trees due to structural weakness can damage property and pose safety risks.
Removal and Replacement Costs: Severely affected trees may require professional removal and replacement, which can be expensive.
Decreased Property Value: Healthy, well-maintained trees enhance property value, while diseased trees can have the opposite effect.

Addressing fungal infections promptly is essential to mitigate these impacts.

Implementing these strategies helps maintain tree health and resilience during periods of extreme heat.

Role of Professional Arborists in Dealing with Tree Fungus

Diagnosis

Accurate Identification: Arborists have the expertise to accurately diagnose fungal infections, distinguishing them from other issues like nutrient deficiencies or pest damage.
Advanced Tools: They may use laboratory testing or specialised equipment to identify pathogens not visible to the naked eye.

Treatment Plans

Customised Strategies: Based on the specific fungus and tree species, arborists develop tailored treatment plans.
Effective Solutions: They recommend the most effective control methods, whether it’s pruning, fungicide application, or soil treatments.

Monitoring and Maintenance

Ongoing Care: Arborists provide regular monitoring to assess the effectiveness of treatments and make adjustments as necessary.
Preventive Measures: They offer advice on practices to prevent future infections, such as proper watering, mulching, and fertilisation.

Safety Considerations

Hazard Management: Trees affected by decay fungi may become hazardous. Arborists assess risks and take appropriate actions to ensure safety.
Safe Removal: If a tree must be removed, professionals can do so safely, minimising damage to surrounding property.

Engaging a professional arborist ensures that your trees receive the best care possible, preserving their health and the safety of your property.

Protecting Your Trees from Fungal Threats

Tree fungi pose significant threats to the health and longevity of trees in South East Queensland. Early detection and proactive management are crucial in preventing the spread of infections and mitigating their impact. By familiarising yourself with common tree fungi, recognizing the signs of infection, and implementing effective prevention and management strategies, you can help protect your trees and maintain the beauty of your environment.

If you suspect your trees may be affected by fungal infections, don’t hesitate to seek professional assistance. At O’Brien’s Tree Care, our certified arborists are equipped with the knowledge and experience to diagnose and treat a wide range of tree fungi. We are committed to preserving the health of your trees and ensuring the safety and aesthetic appeal of your property. To talk to a qualified arborist about your tree’s health, get in touch with O’Brien’s Tree Care on
0431 740 088 or get in touch with us online by clicking here.