A healthy tree can shrug off strong winds. A weak one can fail without much warning, and when it does, the damage can be severe: a crushed roof, a damaged car, a blocked road or worse. The good news is that most dangerous trees show warning signs well before they fall, if you know what to look for.

This guide explains how to spot a hazardous tree, what different warning signs mean and what to do before storm season arrives.

Why Trees Fail in Storms

Trees fail when the load on them exceeds their strength. Strong wind, saturated soil and heavy rain all add stress, and a tree that is already compromised has less strength to resist. Common causes include:

• Internal decay that weakens the trunk or branches
• Root damage or disturbance
• Poor structure, such as narrow or weakly attached branches
• Disease or pest infestation
• Previous storm damage that was never dealt with
• Poor pruning, which can leave weak regrowth

Some failures are sudden, but many trees show signs for months or years before they come down.

Warning Signs of a Dangerous Tree

Leaning trunk

A tree that has always leaned slightly may be stable. A tree that has started to lean, or leans more than before, is a concern. Look for soil heaving or cracks at the base on the side opposite the lean, which can indicate the roots are failing.

Dead or hanging branches

Dead limbs are brittle and can fall at any time. Branches that are broken and stuck in the canopy, often called widowmakers, are especially dangerous.

Cracks and splits

Vertical cracks in the trunk or splits where branches join can signal structural weakness. Included bark, where the bark is pinched between two stems in a tight V shape, is a common weak point.

Cavities and hollow sections

Hollows do not always mean a tree must be removed, but large cavities, especially with a thin wall of remaining wood, can reduce strength significantly.

Fungal growth

Mushrooms, brackets or conks growing on the trunk or at the base often indicate internal decay in the wood or roots.

Damaged or exposed roots

Cut roots from trenching or construction, exposed roots, lifted soil or a sudden change to ground level around the base can all reduce stability.

Thinning canopy or dieback

Sparse leaves, dead tips or leaves that are the wrong colour at the wrong time may point to disease, root problems or stress.

Overloaded or overextended limbs

Large, heavy branches growing out over roofs or driveways can fail under wind or the weight of rain.

How Serious Is the Risk?

Risk depends on two things: the likelihood the tree will fail and what it could hit. A questionable tree in an empty paddock is less of a concern than the same tree beside a home, playground or driveway.

How to Check Your Trees Safely

1. Walk around the tree and look from different angles, in good light.
2. Look up. Check for dead branches, cracks, hangers and thin canopy.
3. Look down. Inspect the base and roots for fungus, lifted soil and damage.
4. Compare over time. Take photos so you can see changes in lean, cracks or growth.
5. Look at the surroundings. Note what is under and around the tree.
6. Do not climb or cut anything risky yourself. Working near a compromised tree is dangerous.

A visual check helps, but it does not replace a professional assessment. Many defects, especially internal decay, cannot be seen from the ground.

What to Do Before Storm Season

• Have an arborist inspect suspect trees, particularly those near buildings, power lines or busy areas.
• Remove deadwood and reduce overextended limbs.
• Address hazards early. Book work before storm season, when providers are busiest.
• Check council rules before removing or heavily pruning protected trees.
• Keep records of inspections and advice.
• Clear gutters and drainage around trees to reduce saturated ground near the base.
• Consider removal if a tree is beyond saving and poses real risk.

If a tree needs to come down, reputable tree removal services in Penrith will assess the tree, the site and the surrounding structures and plan the safest way to bring it down. Proper removal also includes cleanup and can include stump treatment.

What to Do If a Tree Is Already Damaged

If a tree or large limb comes down or is clearly about to:

• Stay well away from the tree and from any fallen power lines
• Call emergency services if there is immediate danger to life or a live line is involved
• Contact your energy provider if wires are affected
• Take photos for your insurer
• Arrange a professional to make the situation safe

When the situation is urgent, such as a tree on a house or blocking access, emergency tree removal Sydney crews can respond quickly, secure the area and remove the hazard safely. Avoid DIY removal after storms, as damaged trees are unpredictable and under tension.

Frequently Asked Questions

How do I know if my tree is dangerous?
Look for a new or worsening lean, dead or hanging branches, large cracks, fungal growth, root damage and a thinning canopy. An arborist can confirm the level of risk.

Can a tree with a hollow trunk be safe?
Sometimes. It depends on how much sound wood remains and the tree's condition overall. A professional assessment will tell you.

When is the best time to check trees for storm risk?
Before storm season, and again after any major weather event.

Do I need approval to remove a dangerous tree?
It can depend on the species, size and location, though rules often allow urgent work for genuinely dangerous trees. Check with the council or an arborist first.

Is a leaning tree always dangerous?
No, but a tree that has recently started leaning or shows soil heave is a serious warning sign.

What should I do if a tree falls on my property?
Keep clear, watch for power lines, call emergency services if needed and contact a professional to make the site safe.

Final Thoughts

Dangerous trees usually give warning signs: leaning trunks, dead branches, cracks, fungus and root problems. Checking your trees before storm season, getting a professional opinion on anything concerning and acting early is far cheaper and safer than dealing with the damage after a tree fails. If a tree looks risky, do not wait for the next storm to find out.