Why Climbing a Tree with Spikes to Trim Branches Kills the Tree

Here is a quick way to spot an unqualified tree worker: they strap on climbing spikes to prune a tree you intend to keep. To a trained arborist, that is an immediate red flag. Spiking a living tree you plan to preserve causes real, lasting harm — and the crews that do it usually make other damaging cuts too. Here is why spikes and pruning do not mix, and how to recognize a professional who knows the difference.

The distinction matters because spikes are not always wrong — there is a right time and a very wrong time to use them, and knowing which is which separates a real arborist from someone who just owns a chainsaw and a set of gaffs.

What spikes do to bark and cambium

Climbing spikes — also called gaffs, hooks, or spurs — are sharpened steel points that dig into the trunk with each step as the climber ascends. On a living tree, every step punctures the protective bark and, critically, the thin cambium layer just beneath it. The cambium is the tree's growth engine and its plumbing, the living tissue responsible for producing new wood and moving water and nutrients between roots and canopy.

Puncturing it is not a cosmetic scratch — it is a wound into the most vital tissue the tree has. And a climber does not step once; they step dozens or hundreds of times over the course of a climb.

Hundreds of open wounds

A single spiked climb can leave dozens or hundreds of puncture wounds spiraling up and down the trunk. Each one is an open door for decay fungi, bacteria, and wood-boring insects to enter the tree. What looks like a clean, finished pruning job from the ground can leave a trunk quietly riddled with entry points for exactly the decay a good arborist works to prevent.

The damage is cumulative and long-term. The tree seals over what it can, but a heavily spiked trunk carries a lasting legacy of wounds that can lead to cankers, decay columns, and reduced vigor years down the road. You paid to have the tree cared for and instead had it injured.

Spikes are for removals only

There is a legitimate time for spikes: when the tree is coming down anyway. On a complete removal, wounding the trunk is irrelevant — the whole thing is being dismantled, so spike away. That is standard, accepted practice and there is nothing wrong with it.

But on a tree you are keeping — any pruning, trimming, or crown work — spikes should never touch it. That single distinction is one of the most basic principles in professional tree care, and a worker who ignores it is telling you they either do not know or do not care about the tree's long-term health.

How professionals actually climb to prune

Qualified arborists ascend and work through a canopy without harming the tree, using rope-and-saddle systems that let them move on their climbing lines, secured to the tree with slings rather than spurs. On many jobs they work from a bucket truck instead, reaching the canopy without climbing at all. No spikes, no trunk wounds — just access to make proper, well-placed cuts.

It takes more skill, better equipment, and more training than strapping on spurs and going straight up, which is part of what separates a professional operation from a "tree guy" with a pickup. The right way is harder, which is exactly why the shortcut is a warning sign.

Spotting unqualified crews

If someone shows up to trim your healthy tree and reaches for spikes, that is your cue to ask questions — or send them on their way. The same crews that gouge trunks with spurs often top trees, leave stub cuts, and strip too much canopy, all of which harm the tree. Cheap, fast, and damaging tend to travel together.

Other red flags: no proof of insurance, high-pressure door-knocking after storms, and vague, unwritten quotes. A professional prunes to recognized standards, uses proper access, and puts the scope in writing.

Insist on proper arborist care

The other cuts that harm trees

Spikes are one warning sign, but the same unqualified crews tend to make a whole family of damaging cuts. Topping — hacking a tree's crown back to stubs — is the most notorious, triggering weak, decay-prone regrowth and permanently disfiguring the tree. Flush cuts that remove the branch collar prevent proper sealing and invite decay. Lion-tailing, stripping all the inner foliage and leaving tufts at the ends, actually increases breakage risk. If a crew spikes a tree they are pruning, watch for these too; they usually travel together, and each one shortens the life of the tree you were trying to care for.

What proper pruning cuts look like

Good pruning is precise and restrained. Cuts are made just outside the branch collar — the slightly swollen ring where a branch meets the trunk — so the tree can seal the wound with its natural defenses. Large limbs are removed in stages to avoid tearing bark. The amount of live canopy removed at once is limited so the tree is not stressed, and cuts are chosen to serve a clear objective: clearance, deadwood removal, thinning, or reduction. Done right, a pruned tree looks natural, not butchered, and is set up to stay healthy. Recognizing the difference protects you from paying to have your trees harmed.

Why standards like ANSI A300 matter

Professional tree care is not improvised; it follows recognized standards. ANSI A300 defines proper pruning practices, and ANSI Z133 governs the safety of the work. These standards exist precisely to codify the difference between care and damage — where to cut, how much to remove, how to work safely. When we say we prune to standard and keep spikes off trees we are keeping, we are pointing at an established body of best practice, not just an opinion. Asking whether a crew works to these standards is a fair, revealing question, and a professional welcomes it while a spike-and-top operation will not know what you mean.

The long-term cost of a spiked tree

The damage from spiking a tree you are keeping is not always obvious the day the crew leaves, which is exactly what makes it insidious. The puncture wounds seal over on the surface while decay quietly works behind them, and years later you may be dealing with cankers, dead patches, structural weakness, or accelerated decline — problems that trace back to that one "cheap" pruning. By then the connection is easy to miss and the tree may need expensive intervention or removal. Protecting a mature tree's health is a long game, and a single spiked climb can quietly undermine decades of growth.

Questions that reveal a real arborist

A few simple questions separate a professional from a spike-and-go operation. Ask whether they will use spikes on your tree and why or why not — the right answer is no on anything being kept. Ask how they prune large limbs and whether they follow ANSI A300. Ask for proof of insurance. A knowledgeable arborist answers these easily and is glad you asked, because it signals you value the tree. A worker who gets defensive, dismissive, or confused by the questions is telling you they are not the crew you want touching a tree you care about.

Red flags of an unqualified tree crew

• Strapping on climbing spikes to prune a tree you're keeping
• Topping trees back to stubs instead of proper reduction
• Flush cuts that remove the branch collar
• Lion-tailing — stripping inner foliage, leaving end tufts
• No proof of insurance and high-pressure storm door-knocking
• Vague, unwritten quotes with no defined scope

The family of harmful cuts that travels with spikes

Spikes on a tree you're keeping are one warning sign, but the crews that use them tend to make a whole set of damaging cuts. Topping — cutting the crown back to stubs — triggers weak, decay-prone regrowth and permanently disfigures the tree. Flush cuts remove the branch collar and prevent proper sealing. Lion-tailing strips the inner foliage and leaves end tufts that actually increase breakage. Cheap, fast, and damaging travel together, and spotting one usually means the others are present too.

Proper pruning is the opposite: precise, restrained cuts just outside the branch collar so the tree seals the wound, large limbs removed in stages to avoid tearing bark, and a limited amount of live canopy taken at once. These practices are codified in the ANSI A300 standard, and asking whether a crew works to it is a fair, revealing question. Your mature trees are worth protecting from well-meaning but harmful 'help.'

At-a-glance: quick reference

Your mature trees are worth protecting from well-meaning but harmful "help." We prune to real arboriculture standards — no spikes on trees we are keeping, proper cuts at the branch collar, and no topping — so your trees stay healthy for the long haul. We serve Granite City, Glen Carbon, and Edwardsville. Call (855) 615-0568 for pruning done the right way.