The Best Tree Stump Killers For Rotting Out Old Stumps
Six stump treatments we'd use to rot a stump down so it digs out with a spade instead of a grinder.
Our quick verdict
Our pick of the best tree stump killer is the Roundup Tree Stump Super Concentrate, the liquid that left one of our garden stumps so rotted it crumbled apart as we dug it out. If you'd rather not measure out a liquid, the Resolva Xtra Tough Tree Stump Killer comes in pre-measured sachets that you pour straight onto the freshly cut stump with very little mess.
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Our Picks At A Glance
- Check price of Roundup Tree Stump Super Concentrate
Best Overall
Roundup Tree Stump Super ConcentrateMost garden stumps up to 45 cm across that you want rotted out
- Check price of Resolva Xtra Tough Tree Stump Killer
- Check price of EcoPlug Maxx Plugs
- Check price of S4M Copper Tree Stump Killer
- Check price of Gallup Super Strength Glyphosate
Best Glyphosate
Gallup Super Strength GlyphosateStumps plus a big weed problem across the rest of the garden
- Check price of SBK Tree Stump Killer
A stump in open lawn and one wedged against a hedge need different treatments. Liquid poured over a stump in the open is quick, but beside shrubs or a packed border a plug that sits inside the wood keeps the weedkiller where it belongs.
You'll also want to know if you're avoiding glyphosate and how long you can wait, as copper nails are the slowest route of all. We've used several of these on our own stumps, and the six treatments cover liquids, sachets, plugs and nails.
How We Tested These Tree Stump Killers
Between our own homes and the gardens at the rentals and Airbnbs we manage, we've had to deal with a fair few stumps. Some we've taken out with a grinder, which we cover in our guide to removing a tree stump with or without a grinder, and others we've left to a stump killer.
Small stumps can come out by hand with a mattock. Anything bigger is a long, sweaty afternoon of digging, and a stump killer takes a few minutes to apply by comparison, so that's where we've focused.
The first photo shows the EcoPlug Maxx plugs going into a large stump beside a fence. Several months on it appeared to be dying back as it should. The second photo is a stump we treated with a strong solution of Roundup's stump killer, which had rotted so thoroughly that it crumbled apart as we dug it out of the gravel.
We judged every treatment on the same points:
- Kill: whether the stump stopped sprouting and the roots died off
- Application: how quick and tidy it was to get the product into the wood
- Speed: how long the stump took to soften enough to dig out
- Versatility: whether the product can be diluted for weeds, brambles or ivy elsewhere in the garden
- Value: how many stumps a pack treats in real use, not just on the label
Where we haven't used a product on enough stumps to judge it ourselves, we've said so and leaned on the manufacturer's figures for coverage and stump sizes.
The Best Tree Stump Killers We Recommend
All six treatments below kill the stump and its roots so it stops regrowing. The glyphosate liquids work fastest, while the plugs and nails suit people who want a cleaner, more targeted job.
Best Overall
Roundup Tree Stump Super Concentrate
Best for: Most garden stumps up to 45 cm across that you want rotted out
Check Price On AmazonRoundup's stump concentrate is the one behind the crumbling stump in our testing photos, and we've had great success with it over the years. You cut the stump fresh, then apply the liquid neat across the face with the supplied pipette or a decent paint brush so it soaks into the living ring just under the bark. From there the glyphosate is drawn down into the root system.
Roundup says one bottle treats up to 16 stumps and that it's suitable for stumps up to 45 cm in diameter. The same concentrate can be diluted for ivy, nettles and Japanese knotweed according to the brand, so whatever is left over won't go to waste.
Don't expect anything to happen overnight, because the formula needs time to work down through the stump and roots. When our test stump did give way, it rotted right through.
What we like
- Glyphosate formula that travels down to kill the roots
- Stump we treated rotted through and broke apart with a spade
- Supplied pipette makes neat application easy
- Rated for stumps up to 45 cm across
- Leftovers can be diluted for ivy and nettles
What to know
- Relatively expensive compared with the other liquids here
- Slow to soften the wood, so it needs patience
Our verdict
Buy the Roundup concentrate if you've got one or more ordinary garden stumps and want the most dependable result from a liquid. It's the one we've had the clearest success with. If you'd rather avoid glyphosate, the SBK Tree Stump Killer is the alternative, and for a big stump where you don't want liquid near other plants, the EcoPlug Maxx plugs are the tidier choice.
Best Value
Resolva Xtra Tough Tree Stump Killer
Best for: One or two stumps on a tight budget
Check Price On AmazonResolva's stump killer comes as two 100 ml sachets of glyphosate concentrate, so there's no measuring and no bottle to store afterwards. You tear one open and pour it evenly over the freshly cut face of the stump, which takes seconds and keeps mess to a minimum.
The box says the two sachets treat up to 6 stumps. That didn't match our experience, as we used a whole sachet on each stump we treated, so plan on two stumps per box if they're a decent size. Even counted that way it's one of the cheaper ways to kill a stump with a product from a well-known garden brand.
Any concentrate you don't need on the stump can be diluted and sprayed onto weeds, though with only two sachets you won't have much spare.
What we like
- Pre-measured sachets with nothing to mix
- Pours straight onto the stump with very little mess
- Low cost for a branded glyphosate treatment
- Diluted concentrate also works on weeds
What to know
- We used a full sachet per stump rather than the three the box suggests
- Only two sachets per box
Our verdict
A stump or two and no wish to keep a half-used bottle in the shed is the situation the Resolva sachets were made for. There's nothing to measure and very little mess. We needed a full sachet for each stump, so budget on two stumps per box, and for several stumps the Roundup concentrate goes further.
Best Professional
EcoPlug Maxx Plugs
Best for: Large stumps and spots close to plants you want to keep
Check Price On AmazonEcoPlug Maxx works differently from the liquids. You drill 13 mm holes around the outer edge of the stump and tap a plug into each one, and every plug releases 300 mg of granular glyphosate straight into the wood. Nothing is poured or brushed, so there's no risk of a spill running into the lawn or a border.
The instructions list how many plugs each stump needs by tree type and size. EcoPlug gives 4 plugs for a birch under 18 cm across as one example, and the brand quotes a success rate of 95 to 100% on treated stumps. It also says the plugs can go in at any time of year and won't harm surrounding plants.
We used them on a large stump beside a fence, shown in our testing photos, and it was dying back as expected several months later. You'll need a drill and a 13 mm bit before you start.
What we like
- Sealed plugs mean no liquid spills near other plants
- Each plug delivers a measured 300 mg dose of glyphosate
- Clear instructions for plug numbers by tree type
- EcoPlug says they work in any weather and season
- Large stump we plugged was dying back months later
What to know
- You need a drill and a 13 mm bit
- Costs more up front than the liquid treatments
Our verdict
Big stumps and stumps near shrubs you want to keep are where EcoPlug Maxx earns its higher price, since the glyphosate goes inside the wood with nothing to spill. The 100-plug kit covers a lot of trees. For one small stump, though, drilling holes is more work than it's worth, and the Resolva sachets are quicker.
Best Nails
S4M Copper Tree Stump Killer
Best for: Chemical-free treatment where you're happy to wait
Check Price On AmazonCopper nails are the old gardener's method. As the copper corrodes inside the stump it releases ions that are toxic to the tree, slowly killing the living wood without any liquid weedkiller. The S4M nails are made specifically for stumps and they're larger than standard copper clout nails, so there's more metal in contact with the wood.
They come in a pack of 50. Some of ours bent as we hammered them into hard wood, so we'd drill small pilot holes first and tap the nails into those.
Results take a long time. On large stumps we've combined the nails with a liquid treatment, as have many gardeners we speak to, but on their own they suit anyone who wants to keep chemicals out of a vegetable patch or a border the kids play near.
What we like
- No liquid weedkiller involved
- Larger than ordinary copper nails for more contact with the wood
- Pack of 50 covers more than one stump
- Easier to fit with pilot holes drilled first
What to know
- Some nails bent when we hammered them into hard wood
- Results can take a long time
Our verdict
Patience is the price of going chemical-free with the S4M copper nails, as results take a long time. Drill pilot holes before you start and they go in without bending. They work well alongside a liquid on a large stump, or on their own where you'd rather keep weedkiller out of a bed. If you want the stump gone sooner, the Roundup concentrate is far quicker.
Best Glyphosate
Gallup Super Strength Glyphosate
Best for: Stumps plus a big weed problem across the rest of the garden
Check Price On AmazonGallup Super Strength is a general glyphosate concentrate rather than a dedicated stump product, but used neat it handles stumps very well. We poured it straight onto a freshly cut stump and it stopped the stump from throwing up new growth.
The real appeal is what else you can do with the bottle. Diluted, it's the same type of strong formula found in many of the weed killers we rate for patios and driveways, so one purchase covers stumps, brambles and paths. It doesn't leave a lasting smell or residue, and the glyphosate becomes inactive once it reaches the soil.
For stumps it has to go on undiluted, and you'll want a dry, still day so it stays on the wood rather than drifting or washing off.
What we like
- Stopped regrowth on the cut stump we treated
- One bottle covers stumps and diluted weed spraying
- No lingering smell or residue
- Inactive once it reaches the soil
What to know
- Needs a dry and still day to apply
- Must be used neat on stumps, which uses it up faster
Our verdict
Gallup Super Strength suits anyone with a stump and a lot of weeds to tackle elsewhere, since the same bottle does both. If the stump is the only job, the dedicated Roundup concentrate is simpler to apply neatly, and the SBK formula is the one to choose if you want to avoid glyphosate.
Best Glyphosate-Free
SBK Tree Stump Killer
Best for: Glyphosate-free stump treatment in autumn and winter
Check Price On AmazonSBK uses a different active ingredient from the rest of the liquids here, so it's the one to pick if you want to avoid glyphosate. It kills at the root to stop the stump regrowing, and the concentrate treats up to 8 stumps according to the brand.
Application is flexible. You can brush it onto the cut face, use a sprayer, or water it on with a watering can, whichever suits the size and position of the stump. Diluted down, it also works on weeds.
Timing matters more with SBK than with the others. It's far less effective in April, May and June while the sap is rising, so treat stumps in autumn and winter. It's still a weedkiller, so keep it off any plants you want to keep.
What we like
- Glyphosate-free formula
- Treats up to 8 stumps from one bottle
- Goes on by brush, sprayer or watering can
- Kills the root to stop regrowth
- Can be diluted for weeds
What to know
- Not effective in April, May and June while the sap is rising
Our verdict
Avoiding glyphosate is the reason to choose SBK, and it gives you the freedom to apply it by brush, sprayer or watering can. Timing is the catch, as it doesn't work in April, May or June while the sap is rising. A stump that needs treating in spring is better suited to the Roundup concentrate.
What To Look For In A Tree Stump Killer
Every product here kills the stump and its roots, but they get there in different ways. The right one depends on how big the stump is, what's growing around it and how long you're prepared to wait before digging.
Liquids, Plugs Or Copper Nails
Liquid concentrates are the quickest to apply. You cut the stump, brush or pour the product across the fresh face and you're done. The downside is that liquid can run off a sloping stump or splash onto nearby plants, so take care in a crowded border.
Plugs such as EcoPlug Maxx put a measured dose of glyphosate inside the wood. There's nothing to spill, which makes them the better choice for stumps beside hedges, shrubs or a lawn edge. They do need a drill and the right bit.
Copper nails avoid weedkiller altogether. They're the slowest of the three and the least predictable, so they suit a stump in a quiet corner that you're happy to leave for a long time.
Glyphosate Or Glyphosate-Free
Glyphosate is the active ingredient in most stump killers, including the Roundup, Resolva, Gallup and EcoPlug products in this list. It's absorbed by the living wood and carried down into the roots. If you want to avoid it, SBK uses a different active ingredient, and copper nails use no weedkiller at all.
Whichever you choose, read the label and wear gloves. Keep children and pets away from treated stumps until the product has dried.
Stump Size And Pack Size
Check the maximum stump diameter and how many stumps a pack claims to treat. Treat those claims with some caution, because in our experience the Resolva sachets covered fewer stumps than the box said. For plugs, the instructions tell you how many to use by tree type and diameter, so count them before you buy.
Big stumps take longer to rot down whatever you use. If a stump is very large or needs to go quickly, renting a grinder or cutting it low with an electric chainsaw first and then treating it is the practical answer.
Time Of Year And Weather
Apply any liquid on a dry, still day so it soaks into the wood rather than washing off or drifting. SBK needs to go on outside April, May and June, and the other liquids work best when the stump is freshly cut and the tree is still drawing moisture down to the roots.
Getting The Stump Ready
Cut the stump as low and as level as you can, ideally with a cordless chainsaw for tidy, low cuts, so the treatment pools on the top instead of running off. Treat the fresh cut straight away, since the outer ring just under the bark is what carries the product down. Chip or shred the cut branches with a garden shredder for woody prunings so they don't sit in a pile while you wait.
Tree Stump Killer Questions We Get Asked
How long does tree stump killer take to work?
Tree stump killer takes months to rot a stump down rather than days or weeks. The product kills the roots fairly quickly, so the stump stops sprouting, but the wood itself takes a long time to soften and break down. Large, dense stumps take the longest. Copper nails are slower again than the glyphosate liquids and plugs.
Do you need to drill holes in a stump before using stump killer?
You need to drill holes for plugs such as EcoPlug Maxx and it helps with copper nails, but brush-on liquids only need a freshly cut surface. Some people drill shallow holes around the edge of the cut face so liquid soaks in rather than running off, which is useful on a stump that isn't level.
Can you use normal weed killer on a tree stump?
A strong glyphosate weed killer such as Gallup Super Strength works on a tree stump if you apply it neat to a fresh cut. Ready-to-use sprays are too weak for this job because they're already diluted for weeds. Dedicated stump killers are made for the purpose and are the simplest choice if the stump is your only problem.
Is it safe to plant where a tree stump has been treated?
Planting is safe once the stump and roots have been dug out and the label's waiting time has passed. Glyphosate becomes inactive when it reaches the soil, but always follow the timings on the product you used. Replace the rotted wood with fresh topsoil before planting, as decaying roots can harbour fungi.
Which tree stump killer would you buy again?
Roundup Tree Stump Super Concentrate is the one we'd buy again. It's the product behind the crumbling stump in our photos, and we've had great success with it over the years. You brush it neat onto a freshly cut stump with the supplied pipette. The SBK Tree Stump Killer is the alternative if you'd rather avoid glyphosate.
Will the Resolva sachets really treat six stumps?
Not in our experience. The box says the two sachets treat up to 6 stumps, but we used a whole sachet on each stump we treated. Plan on two decent-sized stumps per box. For several stumps, the Roundup Tree Stump Super Concentrate goes further, with Roundup saying one bottle treats up to 16.
Can copper nails kill a stump without any weedkiller?
Copper nails are the chemical-free route, but results are slow and less predictable than glyphosate. On our larger stumps we've paired the S4M nails with a liquid treatment. Drill small pilot holes first, because some of ours bent when hammered into hard wood. On their own, they suit anyone happy to wait.
Is EcoPlug Maxx worth the extra cost for a big stump?
It's worth it for large stumps and stumps close to plants you want to keep. Each plug sits in a 13 mm drilled hole and releases 300 mg of granular glyphosate into the wood, so there's no liquid to spill. You need a drill and costs rise against liquids, but the large stump we plugged beside a fence was dying back months later.
Our Top Tree Stump Killer Picks
Roundup Tree Stump Super Concentrate is our first choice for most garden stumps, and it's the one that left our test stump crumbling apart at the end of a spade. EcoPlug Maxx plugs are the better pick for big stumps or anywhere you can't risk liquid running onto other plants.
If you'd rather avoid glyphosate, the SBK Tree Stump Killer does the job in autumn and winter, and the S4M copper nails suit a stump you're happy to leave for a long while.
Archie is our gardening specialist. He started out as an apprentice at a gardening firm, built up his own knowledge from there and now writes most of our garden content.