Trees rarely fail without warning. They fail without anyone noticing the warning, which is a different thing.
In the weeks before a tree comes down, there is almost always something visible from the ground: a crack, a change in the lean, soil lifting on one side of the base. Homeowners walk past it every day without registering it, because they are looking at the tree they remember rather than the tree that is there now.
Late winter is a good time to look properly. Before spring growth fills the canopy, dead limbs, cracks and poor branch unions are still easy to spot. It also gets you ahead of the westerlies that push through the Blue Mountains and Western Sydney in August, well before the official storm season starts and it does not start until September. That combination catches a lot of people out.
Here are seven things worth checking on your own property. None of them require a ladder, a licence or any special equipment. All you need is 10 minutes and a decent look.
1. A lean that has changed
Plenty of trees lean. A tree that has grown at an angle over decades has usually built reaction wood to compensate, and it can be perfectly stable.
The concern is a lean that is new, or one that has become more pronounced. The tell is at the base, not the top. Look for soil that is cracked, mounded or lifted on the side opposite the lean, and for exposed roots on the leaning side. That pattern suggests the root plate is moving.
If the ground around the base looks disturbed and you can’t explain why, treat it seriously. A root plate that is already moving will not hold through a strong westerly.
2. Cracks or splits in the trunk or major limbs
Vertical cracks running up the trunk, or splits at the point where a large limb joins the stem, are structural defects. Wind loads the tree, the crack opens further, and eventually the section separates.
Look closely at anything that has already partly failed. A limb that tore and is still hanging on by a strip of bark is not recovering. It is waiting.
Fresh cracks often show lighter-coloured wood inside. Older ones may have started to callous over at the edges, which tells you the defect has been there a while and the tree has been working around it.
3. Deadwood in the canopy
Dead branches have no flex. They are brittle, they do not bend with the wind, and they are the single most common thing to come out of a canopy during a wind event.
From the ground, deadwood shows up as bare limbs with no foliage, often with the bark falling away or already gone. In winter this can be harder to spot on deciduous trees, so focus on the branch structure rather than the leaves. A dead limb has a different shape to a dormant one: no fine twig growth at the tips, and a grey, weathered surface.
A few dead twigs is normal. Substantial dead limbs sitting over a roof, a driveway or a play area needs a closer look.
4. Fungal growth at the base or on the trunk
Bracket fungi, mushrooms at the base, or fungal growth on exposed roots usually indicate decay inside the tree. The visible fruiting body is the smaller part of the story. What matters is how far the decay extends through the structural wood.
This one is easy to underestimate because the canopy can look completely healthy. A tree can carry full foliage while the base of the trunk is substantially hollow. The canopy is fed by tissue just under the bark; the strength comes from the wood underneath, and that is what decay attacks.
Fungal growth at the base of a large tree near a structure is worth a professional assessment. Not a panic, an assessment.
5. Tight, V-shaped branch unions
Where two stems of similar size grow up together in a narrow V, bark can become trapped between them as they expand. This is called included bark, and it means the two stems are pressed against each other rather than properly joined.
These unions are structurally weak. Under wind load, they split, and because the failure happens low on the tree, the piece that comes down is usually large.
Wide, U-shaped unions are generally strong. Narrow V-shaped unions on a mature tree, particularly with a visible seam or a line of trapped bark running down from the fork, are worth flagging.
6. Hollows, cavities and missing bark
A cavity in the trunk is not automatically a death sentence. Trees compartmentalise decay, and many hollow trees stand for decades and provide excellent habitat.
What matters is the proportion. A small opening with a thick shell of sound wood around it is very different to a cavity where the remaining wall is thin. From the ground you can sometimes gauge this by the size of the opening relative to the trunk diameter, but honestly this is where you want a qualified opinion rather than a guess.
Large patches of missing or loose bark on the trunk point to underlying problems too. Bark does not fall off healthy tissue.
7. A one-sided or top-heavy canopy
Canopy shape matters more than most people realise. A tree with all its weight on one side, or a dense mass of foliage concentrated at the top, has a centre of gravity working against it.
This often happens after previous bad pruning. Topping a tree produces a flush of weakly attached regrowth at the cut points, which then grows heavy. Ten years on, you have a tree carrying a lot of weight on unions that were never designed to hold it.
It also happens naturally where a tree has grown towards light, or where one side was cleared for a building or a fence line. Either way, uneven loading and sustained wind from an unfamiliar direction is a poor combination.
What to do if you have spotted something
Not every one of these means the tree has to go. Plenty of trees with defects can be managed through pruning, weight reduction, or simply monitoring on a sensible schedule.
What they do mean is that a guess is not good enough. If you have found something on this list, particularly on a large tree near your house, get a qualified arborist to look at it. We assess trees at no charge and will tell you honestly whether it needs work, whether it can be managed, or whether it is fine as it is.
If removal is the right call, our large tree removal service covers controlled sectional dismantling. Steep, narrow or built-up sites are standard work for us, not an exception.
When it stops being an assessment and becomes an emergency
There is a point where this is no longer a planning conversation.
A tree already resting on a roof. A limb hanging above a driveway. A trunk that has split and separated. Soil visibly lifting at the base of a large tree in the current wind. In those situations you need someone on site quickly, not a booking for next month.
That is emergency tree removal, and we prioritise it ahead of standard work with after-hours call-out.
Two things to know before you call anyone. If a power line is involved, stay clear and contact your electricity network provider first. If there is an immediate risk to people or property during a storm event, the NSW SES is the agency to call, and its guidance on what to do during a storm is worth reading before you need it.
Ten minutes now, or a claim later
The trees on your property have been growing for longer than you have owned them, and they will keep changing whether or not anyone is watching.
A walk around the block before the winds pick up is the cheapest risk management available. If something on this list is looking back at you, we’re happy to come and take a look.