Using a chemical stump remover like Bonide Stump Out or Gordon’s Stump Remover takes about an hour of drilling and pouring, followed by a 4 to 6 week wait for the stump to become soft, porous, and ready to burn or chop out.
A stubborn stump sitting in your yard is an eyesore and a tripping hazard. You could pay for a grinder, but a $10 bottle of potassium nitrate granules and a drill do the same job over a few weeks. The process is simple: drill the right holes, add the granules and water, and let chemistry break down the wood from the inside. Here’s exactly how to do it without wasting a weekend.
What Does Stump Remover Actually Do?
Stump remover granules contain potassium nitrate, a chemical that feeds the wood-decaying fungi already living in the stump. Once activated with water, the potassium nitrate accelerates natural decomposition, turning the dense stump into a dry, sponge-like cellulose. After 4 to 6 weeks, that softened material either burns away quickly with kerosene or shatters under an axe. The process only works on dead, seasoned stumps — it won’t kill a living tree.
Tools and Materials You’ll Need
Before you start, gather everything in one place. You don’t want to stop mid-drill to hunt for a longer bit.
- 1-inch drill bit (at least 12 inches long)
- Power drill
- Stump remover granules (Bonide Stump Out, Gordon’s, or Southern Ag)
- Water source (hose or bucket)
- Kerosene or fuel oil (for burning) or a hatchet (for chopping)
- Charcoal briquettes (safer fire starter)
- Safety glasses and gloves
The research behind the best products on the market is detailed in our roundup of the best chemical stump removers, if you want to compare options before buying.
The Step-by-Step Application Process
Step 1: Drill the Holes Correctly
Hole placement determines how fast the granules spread and whether the stump burns evenly. Drill two types of holes.
- Vertical holes: Drill straight down from the top of the stump, 10 inches deep. Space them about 1 inch inside the bark line.
- Angled holes: Drill into the side of the stump, 4 to 5 inches deep, slanting downward so they meet the bottom of the vertical holes. These angled holes create a ventilation channel that helps the stump burn later.
How many holes you need depends on the stump’s diameter. For a 12- to 18-inch stump, drill two sets of vertical-and-angled holes. For any stump larger than 18 inches, increase to four sets.
Step 2: Pour the Granules
Pour 4 to 6 ounces (roughly half a cup) of granules into each hole. A full 1-pound bottle of Bonide Stump Out treats one 12- to 18-inch stump. Gordon’s and Southern Ag labels specify the same 4- to 6-ounce rate per hole. Don’t skimp — underdosing means the decomposition slows down or stalls.
Step 3: Add Water
Fill each hole completely with water. Water dissolves the granules so the potassium nitrate soaks into the wood fibers. Hot water penetrates faster, but tap water works fine. If your area is dry and rainfall is infrequent, re-soak the stump every week or two to keep the reaction going.
Step 4: Wait 4 to 6 Weeks
Leave the stump alone. The decomposition happens underground where you can’t see it, so don’t dig around the stump to check. After four weeks, test a spot with a screwdriver — if it sinks easily into soft, crumbly wood, the stump is ready. If not, wait another two weeks.
Step 5: Remove the Stump – Two Options
Once the stump has decomposed, you have two removal paths.
Burning. Pour kerosene or fuel oil into the holes and let it absorb for 15 to 30 minutes. Place a charcoal briquette on top of each hole and light it. The stump will smolder from the inside out, often burning down to below ground level. Use a long torch or barbecue lighter, wear safety glasses, and never use gasoline — it vaporizes explosively.
Chopping. If burning isn’t allowed in your area, the decomposed stump is now soft and brittle. Drive a hatchet or axe into the wood — it will break apart in chunks like rotted lumber. Dig out the large pieces and fill the hole with soil.
Burning vs. Chopping: Which Should You Choose?
| Removal Method | Best For | Key Considerations |
|---|---|---|
| Burning | Large stumps, least physical effort | Check local burn ordinances; never use gasoline; keep fire away from dry grass |
| Chopping | Small to medium stumps, no-burn zones | More physical work; decomposed wood is soft but root ball may still be tough |
| Charcoal only | Dry, fire-safe conditions | Safer than kerosene; requires more briquettes for large stumps |
| Kerosene | Fast, hot burn | Must let fuel absorb fully; longer soak time improves results |
Common Mistakes That Wreck the Results
Most failures come from skipping one simple part of the process.
- Skipping the angled side holes. Without them, the stump won’t get enough oxygen to sustain a burn. The granules also don’t spread as far into the wood.
- Not adding enough water. Dry granules sit inert. The wood fibers need moisture to soften and let the potassium nitrate move deeper.
- Using gasoline. Gasoline ignites explosively, produces toxic fumes, and can contaminate the soil around the stump. Kerosene or fuel oil is the only safe liquid fuel.
- Underestimating stump size. A 2-foot stump doesn’t need two holes — it needs seven sets.
- Burning during a dry spell. A smoldering stump can ignite nearby leaves, roots, or grass. Burn only when the ground is damp and fire risk is low.
Safety Rules That Matter
Potassium nitrate is low-toxicity, but it can irritate skin — rinse any contact area with water. Always burn stumps well away from structures, overhanging branches, and dry vegetation. If your county requires a burn permit, get it first. And never leave a burning stump unattended — it can smolder for hours underground and flare up later.
When Stump Remover Won’t Work
The product does nothing on a freshly cut, living stump. The tree’s natural moisture and sap block the potassium nitrate from penetrating the wood. Let the stump season for at least 6 to 12 months after cutting, or until the bark starts peeling and the wood surface cracks. On a green stump, rent a grinder or wait — there is no shortcut.
Final Process Checklist
Run this checklist before you light a match or swing an axe.
- Stump is dead and dry; bark is loose or cracked.
- Holes drilled to 10 inches deep with 1-inch bit.
- Angled side holes drilled to meet vertical holes.
- Granules poured at 4–6 oz per hole.
- Holes filled with water; stump kept moist during waiting period.
- 4 to 6 weeks elapsed; stump feels soft to a screwdriver test.
- Burn permit checked (if applicable).
- Kerosene or charcoal ready; gasoline left in the garage.
- Safety glasses and a long lighter on hand.
FAQs
Can I use stump remover on a live tree?
No. Potassium nitrate accelerates decomposition of dead wood only. On a living stump, the sap and moisture block the chemical from penetrating, and the tree may even try to regrow. Cut the tree, let the stump dry for a season, then apply the remover.
How long does it take for stump remover to work?
Manufacturer labels and user reports agree on 4 to 6 weeks for the stump to fully decompose into a soft, porous material. Larger stumps or cold weather can push the timeline toward the 8-week mark. You’ll know it’s ready when a screwdriver pushes in with little resistance.
Do I need to remove the dirt around the stump first?
No. Drill directly through any soil or grass growing on top of the stump. The water and granules will soak downward. Removing dirt just creates extra cleanup work without improving the chemical reaction.
Is it safe to burn a stump treated with potassium nitrate?
Yes, when done correctly. Potassium nitrate is an oxidizer, which helps the stump burn more completely and with less smoke than untreated wood. Just follow the label’s fuel guidelines — use only kerosene or fuel oil, never gasoline, and check local burn restrictions first.
What happens if I don’t burn or chop the stump after 6 weeks?
The stump will continue decomposing naturally, but at a much slower rate. It eventually rots into the ground on its own over a year or two. The treatment just gets you a usable result in a month and a half instead of waiting.
References & Sources
- Bonide. “Stump Out DIY Stump Removal Granules.” Official product page with application instructions and active ingredient details.
- Bonide. “Stump Out Label.” Full label with drilling specifications and burn instructions.
- Southern Agricultural. “Stump Remover Label.” Label covering hole patterns, application rates, and safety warnings.
- Gordon’s. “Stump Remover Label.” Label with application rates and 4–6 week effectiveness cycle.
- University of Illinois Extension. “What to Do with a Tree Stump? A Guide to Tree Stump Removal.” Extension guide covering stump removal options and safety considerations.