Eucalypts are the trees that make people nervous. A gum can look half dead for a season and bounce back, or look perfectly healthy on Monday and drop a limb the size of a car on Friday. On the exposed blocks across Werribee, Tarneit, Point Cook and out through the Melton ring, where the river red gums and sugar gums grow big and carry a lot of weight up high, the question we get asked more than any other is some version of: is this tree dead, dying, or fine?

Here is how to read a gum, what the common signs mean, and when removal is the right decision rather than the nervous one.

Gums shed. That is normal

Start with the things that look alarming but are not. Eucalypts drop leaves year-round rather than in a single autumn, so a carpet of leaves under a gum in January is not a sign of anything. Many species shed bark in strips or sheets every summer, which is how a smooth-barked gum stays smooth, and the piles of bark under a river red gum or a lemon-scented gum in February are simply the tree renewing itself. Gums also drop small twigs and branches constantly, particularly in a dry spell, and a healthy tree can look thin in the crown at the end of a hot, dry summer and thicken up again with rain.

None of that means the tree is dying. It means it is a gum.

The signs that matter

Dead wood in the crown. Look up. A healthy eucalypt can carry some dead branches, but a crown that is more than about a quarter dead, or where the dead wood is concentrated in the upper canopy, is a tree under stress. Dead limbs on a gum are also the ones that drop, so they are a hazard whatever the tree's overall health.

Dieback from the tips. Branches that are dying from the outer ends inward, with leaves browning and dropping from the tips first, indicate the tree is struggling to get water to its extremities. Drought stress, root damage from nearby excavation or a driveway, and waterlogging in the heavy clay after a wet winter all cause it.

Epicormic growth. Clusters of small leafy shoots sprouting directly from the trunk and main limbs are the tree's emergency response. A gum that has been stressed by drought, fire, root damage or heavy lopping throws out this growth to keep itself alive. A little is normal; a trunk covered in it while the main crown thins is a tree in trouble.

Fungal brackets, hollows and oozing. Fungal fruiting bodies at the base or on the trunk, large hollows, cavities where limbs have torn out, and dark staining or sap oozing from the bark all point to decay in the wood. Decay is what turns a tree that looks fine into one that fails without warning, and it is the reason a photo is often not enough to assess a big gum.

Bark and borers. Bark that is coming away in large plates with tunnelling or frass underneath, rather than shedding in the normal seasonal strips, suggests borers or disease in the wood beneath.

A lean that is new. A gum that has always leaned is usually fine; it has grown that way. A gum that has started to lean, or where the soil on one side of the base has lifted or cracked, may be losing its root plate, and that is urgent, especially on the saturated clay of a Werribee winter.

Dead or dying is not the same as dangerous

A tree can be in poor health and pose no risk, because there is nothing under it. It can also be in fine health and be a hazard, because it is a large river red gum with a heavy horizontal limb over the roof. When we look at a gum the questions are: how healthy is it, how likely is it to fail or drop a limb, and what is underneath if it does? A stressed tree over an open paddock corner can be left and monitored. A healthy gum with a suspect limb over the bedroom can be pruned. A gum with decay at the base leaning toward the neighbour's house comes out.

The scratch test

For a small tree or a branch you can reach, scratch a little bark with a thumbnail. Green and moist underneath means living tissue; brown, dry and brittle means dead. On a large gum this tells you about the branch you scratched and nothing about the crown thirty metres up, so use it as one clue rather than a verdict.

What to do next

If the tree has dead limbs over a house, driveway, play area or road, have them dealt with promptly regardless of the tree's overall health. Deadwooding and crown thinning through our tree lopping and pruning service removes the hazard while keeping the tree, and on a mature gum that is often the right answer. If the tree is showing decay, a new lean, or a crown that is mostly dead, removal is usually the safe and cheaper course, and it is what our tree removal service is for. And if a limb has already come down in a storm, our emergency and storm damage crew makes the tree safe first and sorts the rest afterwards.

Before any removal, check whether a permit is needed. Wyndham has planning overlays and local laws that can protect native and significant trees, and our page on tree removal permits in Wyndham explains how to find out.

Send us photos

You do not need to decide alone. Photograph the whole tree from a distance, the base of the trunk, any hollows or fungus, and the worst of the dead wood, and send them with your address. Often we can tell you straight away whether the tree needs pruning, monitoring or removal, and if it needs a closer look, we come out. Werribee, Hoppers Crossing, Tarneit, Point Cook, Truganina and the Melton ring are all covered.

Is My Gum Tree Dead or Dying? How to Tell, and What to Do About It in Werribee