Most homeowners don't think about their trees until something goes wrong — a limb on the roof after a storm, a crack in the trunk they hadn't noticed, a neighbor mentioning that the big maple looks "tired." The problem is that by the time tree trouble is obvious, it's often advanced. These nine signs, ranked roughly from most urgent to least, tell you when a tree needs professional attention now — and which ones point toward removal rather than trimming.
1. Dead or dying canopy — High urgency
What it means: When large sections of the crown fail to leaf out in spring, or the top of the tree dies back while the lower limbs look fine, the tree is in serious decline. In McLean County, canopy dieback in an ash tree is the classic signature of emerald ash borer; in other species it can signal root damage, disease, or severe stress. A tree that has lost most of its canopy won't recover — dead wood doesn't come back.
What to do: If more than half the canopy is dead, removal is usually the answer. A dead standing tree sheds limbs unpredictably and can fail in the next storm. Get an assessment promptly, especially before spring storm season.
2. Major trunk damage or deep cracks — High urgency
What it means: The trunk is the tree's structural spine. Deep vertical cracks, large wounds where bark has been torn away, or a trunk that has split into a V with included bark are all structural failures. Lightning strikes are a common cause in Central Illinois — a strike can split a trunk from crown to root in a single storm. If you can see daylight through a crack, or the crack extends into the wood beneath the bark, the trunk's integrity is compromised.
What to do: Minor surface cracks can sometimes be monitored, but deep or widening cracks mean the tree can split apart — often in a windstorm, often onto something expensive. Removal is usually warranted.
3. Sudden or severe leaning — High urgency
What it means: A tree that has always leaned slightly is usually fine — that's just how it grew toward the light. A tree that starts leaning, or whose lean has suddenly gotten worse after a storm, is telling you its root plate is failing. Check the ground around the base: heaving soil, exposed roots on the uphill side, or a visible gap between the root plate and the earth are all red flags that the tree is in the process of falling over.
What to do: A newly leaning tree near a house, driveway, or power line is an emergency. Call for an assessment immediately — this is one case where waiting is genuinely dangerous.
4. Root damage — Moderate to high urgency
What it means: Roots are the tree's anchor and its food supply. Construction is the usual culprit: trenching for a new driveway, grading, or utility work that severs major roots on one side of the tree. The damage often doesn't show in the canopy for a year or two, then the tree declines rapidly. Fungal fruiting bodies (mushrooms) growing from the root flare at the base of the trunk are another sign — they indicate decay in the structural roots.
What to do: Minor root damage on a healthy tree can sometimes be managed with proper care. But if the structural roots on one side are gone and the tree leans toward the damaged side — or if decay fungi are present at the base — removal is the safe call.
5. Fungal growth on the trunk or root flare — Moderate urgency
What it means: Mushrooms or shelf-like conks growing from the trunk, root flare, or major limbs mean the wood inside is rotting. The fungus you see is just the fruiting body — the real decay is hidden inside, hollowing out the tree's structure. A few small mushrooms at the base of a stump are normal; conks on a living tree's trunk are not.
What to do: Don't ignore this one, but don't panic either. Have the tree assessed — an experienced professional can often tell from the location and extent of the fungal growth whether the tree is structurally compromised or can be managed with pruning and monitoring.
6. Hollow trunk — Moderate urgency
What it means: Many older trees — especially silver maples, which are common in Bloomington-Normal yards — develop hollow centers from old wounds and decay. Surprisingly, a hollow tree isn't always doomed: a tree can remain standing for years with a hollow trunk if the outer shell of living wood is thick enough. But the thinner the shell, the higher the risk of failure, and there's no way to judge shell thickness from the outside.
What to do: Get it evaluated. If the tree is hollow but the shell is sound and it's not over a target (house, play area, driveway), it may be a candidate for monitoring or crown reduction. If it's hollow and leaning over your roof, removal is the prudent choice.
7. Dropping large limbs — Moderate urgency
What it means: Silver maples and some other fast-growing species are notorious for dropping big limbs in storms — or even in calm weather when the wood is weak. Occasional small deadwood is normal and is fixed with routine pruning. But if a tree is repeatedly dropping limbs big enough to damage a car or hurt a person, the tree's structure is failing.
What to do: A thorough crown cleaning (removing dead, weak, and crossing limbs) often solves this — it's one of the most common reasons people call for trimming. If the whole canopy is weak or the drops continue after pruning, the tree may be in decline and removal should be on the table.
8. Signs of emerald ash borer — Moderate urgency (time-sensitive)
What it means: Canopy dieback starting at the top, D-shaped exit holes, bark splitting, heavy woodpecker damage, and water sprouts on the trunk are the classic EAB progression. In McLean County, an untreated ash showing these symptoms is dying — the question is only how fast. (Full details in our emerald ash borer guide.)
What to do: Treatment is only viable if caught very early. For most symptomatic ash trees, plan the removal sooner rather than later — dead ash becomes brittle and hazardous, and waiting turns a routine removal into an emergency one.
9. Proximity risks — the tree is fine, but its location isn't — Lower urgency, but real
What it means: Sometimes the tree is healthy and the problem is geometry: roots cracking the foundation or lifting the driveway, limbs rubbing the roof and feeding squirrels into the attic, or a fast-growing species planted six feet from the house that will be a 60-foot problem in a decade. In older Bloomington neighborhoods, mature trees planted too close to homes decades ago are a common version of this.
What to do: This is the one category where you have time to plan. Pruning can buy years in some cases, but if the tree will inevitably outgrow its space, removing it while it's small and manageable is far cheaper than removing it at 60 feet.
Removal is the last resort, not the first. Many tree problems — deadwood, minor lean, crossing limbs, early disease — are treatable with proper pruning and care. A trustworthy tree professional will tell you when trimming is enough and won't push removal on a tree that can be saved. But when the signs above point to structural failure, delaying doesn't make the tree safer — it makes the eventual removal more dangerous and more expensive. When in doubt, get an on-site assessment.
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