How to Assess the Safety of Large Trees on Your Property

Got a giant gum or towering jacaranda in your backyard? While big trees add charm and shade, they can also become a serious safety risk if not properly maintained. If you’ve ever searched for an arborist, chances are you’ve had a few questions about your leafy giants. Assessing the health and safety of large trees isn’t just for the pros—you can learn the basics too.

Let’s walk through everything you need to know to spot trouble early and keep your trees strong, safe, and standing tall.

Understanding the Importance of Tree Safety

The Risks of Neglected Trees

A beautiful tree can become a massive hazard if it’s left unchecked. Weak branches, hollow trunks, and unstable roots are disasters waiting to happen, especially during Sydney’s wild summer storms.

Tree Safety and Property Damage

Falling limbs can damage cars, roofs, fences, or worse—injure someone. The bigger the tree, the higher the risk. That’s why early assessment is crucial. Prevention will always be cheaper than emergency removal.

Signs of a Dangerous Tree

Visible Structural Damage

Start by simply observing. Large cracks in the trunk or branches, cavities, peeling bark, or fungi growing at the base? These could be signs your tree is in serious trouble.

Leaning or Shifting Trunks

A tree leaning more than 15 degrees from vertical (especially if it’s new) is a red flag. Look for heaving soil around the base or exposed roots—both signs of root failure.

Deadwood and Broken Branches

Dead branches are brittle and unpredictable. If you spot deadwood high up or if branches break easily in the wind, it’s time to act.

Factors Affecting Tree Stability

Soil Conditions and Root Health

Poor drainage, compacted soil, or erosion can weaken root systems. A healthy tree relies on strong roots for anchorage. Keep an eye on pooling water or exposed root flare.

Tree Species and Growth Patterns

Not all trees are created equal. Some—like willows—are more prone to splitting, while others naturally grow lopsided. Understanding your species helps you assess risk more effectively.

Weather and Environmental Stress

Heavy winds, droughts, and flooding all impact tree health. Sydney’s unpredictable weather means trees here often endure significant stress, especially during storm season.

Tools for Assessing Tree Health

Visual Tree Assessment (VTA)

A trained eye can spot danger signs with a simple walk-around. Look at the crown (top), trunk, and roots. Are the leaves lush or sparse? Any cracks or fungal growth?

Resistograph and Sonic Tomography

These are specialist tools arborists use to detect internal decay. A resistograph drills a fine needle into the wood to measure resistance, while sonic tomography uses sound waves to map internal damage.

Using Drones for Canopy Checks

Modern arborists often use drones to get a bird’s-eye view of the canopy. It’s especially useful for inspecting trees that are too tall or dense for a full view from the ground.

Professional Tree Inspection: When to Call an Expert

What an Arborist Does

An arborist Sydney expert isn’t just someone who cuts trees—they’re trained in tree biology, diseases, and safe pruning practices. They can assess risk, diagnose issues, and recommend the best solutions.

Choosing a Qualified Arborist in Sydney

Make sure they’re AQF Level 3 or above and insured. Look for members of Arboriculture Australia or the International Society of Arboriculture (ISA). Reviews and referrals also go a long way.

How Often Should You Get Trees Inspected?

Ideally, get large trees inspected every 12–18 months, or after major storms. For older or high-risk trees, annual checks are even more important.

Common Tree Diseases and Pests

Fungal Infections

Mushrooms at the base or blackened bark may signal rot. Root rot and cankers are among the most common fungal threats to Sydney’s trees.

Insect Infestations

Borer holes, sap oozing, or leaves being eaten? Pests such as psyllids, beetles, and borers can cause significant damage. Left untreated, infestations can significantly weaken trees.

Signs Your Tree Is in Trouble

Wilting leaves in summer, early leaf drop, or sparse foliage are signs of stress. Discolouration, sticky residue, or odd growths should prompt a closer look.

Maintenance Practices for Healthy Trees

Pruning for Safety

Regular, strategic pruning removes hazardous limbs and enhances the structure. Avoid “lopping” or topping—it can cause more harm than good.

Watering and Fertilisation

Young and stressed trees benefit from deep watering during dry periods. Balanced fertiliser helps boost their defences against pests and disease.

Protecting Root Zones

Avoid parking or heavy foot traffic near the base. Roots need space and oxygen to stay strong—compact soil suffocates them.

Legal Considerations for Tree Safety on Your Property

Liability for Tree Damage or Injury

If a branch falls and causes injury or damage to your neighbour’s property, you could be held liable, especially if the tree was neglected.

Council Regulations and Tree Removal Permits

In Sydney, many councils protect trees over a certain size. Before pruning or removing a tree, always check local tree preservation orders. Removing a tree without obtaining approval can result in substantial fines.

Conclusion

Large trees are majestic, but they come with responsibility. Assessing their safety might feel overwhelming at first, but once you know what to look for—and when to call in the experts—it becomes second nature.

Whether you’re keeping your family safe, avoiding legal headaches, or just doing right by your garden, regular tree assessments are a smart move. And if you’re unsure where to start, a qualified arborist in Sydney can guide you every step of the way.

So, grab a cup of tea, head outside, and give your trees a once-over. They’re more than just background scenery—they’re a living, growing part of your home. Look after them, and they’ll return the favour.