Does the hole sink after stump grinding?
Yes, it can. Purdue Extension says: “Also, there will be significant settling of the ground below the stump as it decays and loses its structural fiber.” This is soil settling. It is normal, and it often shows up as a dip in the lawn weeks or months after the work.
Purdue Extension also says it expects the stump area to need help: “The soil should be added to replace the below ground roots and stump.”
Why does the ground settle?
Because wood and roots are left under the soil, and they shrink as they rot. Iowa State Extension says the grinder chews away the stump and large lateral roots, “typically down 8 to 12 inches.” The chips go into the hole. Roots below that depth stay.
Purdue Extension says it “can take several years to fully decompose the stump unless it was ground very deeply or removed with an excavation machine.” As the wood breaks down, it takes up less space. The soil above it drops into the gap.
| What is under the surface | What happens | Result at the surface |
|---|---|---|
| Ground chips mixed with soil | Chips break down and pack down | Dip in the filled hole |
| Roots left below the cutter | Roots rot over years | Slow, uneven settling |
Both rows come from Purdue and Iowa State Extension.
How much topsoil does the hole need?
The sources give no volume, because it depends on how deep the grinder went. Illinois Extension says: “Depending on how far down a stump is ground, you may be left with a large hole.” For turf, it recommends that you “haul off the chipped stump debris and fill the hole with quality topsoil.” See topsoil and backfill.
Purdue Extension adds the rule that matters here: add soil to the stump area, “and a little additional soil mounded to compensate for some decay.” So fill the hole level, then add a low mound. Do not tamp it flat and call it done. Depth of the original cut also matters; see how deep stump grinding goes.
Should I fill the hole with the chips?
No, not if you plan to plant. Illinois Extension says “Wood material mixed in with the soil can tie up nitrogen as the wood breaks down, making it difficult to grow lawn, or another plant where the tree once stood.” Iowa State Extension says “Ideally, these shavings are removed before new topsoil is added and the area is replanted.”
If you leave chips in the hole, expect more settling than with topsoil, because chips break down. The sources do not measure this. They only say the wood decays and the ground settles.
Cincinnati Stump Grinding says: “And if you’d like those wood chips hauled away and replaced with fresh topsoil, we offer those services too.” Read about the chip haul-away and topsoil service. Ask about it when you request your free estimate.
When should I add more soil?
Add soil when you see a dip. Check after a few heavy rains and again each season. For grass over the spot, Purdue Extension says to add slow-release turf fertilizer and to “Maintain adequate moisture and look for signs of yellowing, indicating low nitrogen levels.”
A simple routine:
- Look at the spot after heavy rain.
- If a dip shows, add topsoil and level it with a slight mound.
- If you have sod or seed there, keep it watered.
- Look again each spring and fall for the first few years.
The sources do not give a schedule. This routine just follows their logic: the ground settles as wood decays, so check back.
What if the dip is large, sudden or near a building?
Settling from decay is gradual. A sudden or deep drop is a different case. The extension sources do not cover it. If a dip is deep, grows fast, or sits near a foundation, a patio or a pipe, ask a local professional to look at it. See also stump grinding near a house foundation.
Does replanting change anything?
Yes. Purdue Extension does not want new trees or turf “immediately over the top of existing stumps in landscapes.” Read can you plant grass after stump grinding and can you plant a tree after stump grinding. For the whole plan in order, see what to do after stump grinding.
Next step
For haul-away of the chips and fresh topsoil in the hole, see the chip haul-away and topsoil service. Call (513) 587-6772 or send photos for a free estimate.
Frequently asked questions
Does the ground sink after stump grinding?
It can. Purdue Extension says there will be significant settling of the ground below the stump as it decays and loses its structural fiber. Buried wood and roots shrink as they rot, and the soil above drops into the space they leave.
How long does it take for a ground stump to settle?
The sources give no set time. Purdue Extension says it can take several years to fully decompose the stump unless it was ground very deeply or removed with an excavation machine. Expect the spot to drop in stages, not all at once.
How much topsoil should I add?
The sources give no volume. Illinois Extension says to fill the hole with quality topsoil. Purdue Extension adds a little additional soil mounded over the spot to make up for decay. After that, add soil to any dip that forms.
Should I fill the hole with the wood chips?
Illinois Extension and Iowa State Extension advise against relying on chips if you want to plant. Wood mixed into soil can tie up nitrogen and change soil structure. They advise removing the chips and using quality topsoil.
Is a dip over a ground stump a sinkhole?
The extension sources describe it as settling as buried wood decays. They do not use the word sinkhole. If a dip is deep, sudden or near a foundation, ask a local professional to look at it.
Terms on this page
Sources
- Purdue Extension: Question: Can I Plant Grass Over Newly Removed Stump
- University of Illinois Extension: What to do with a tree stump
- Iowa State Extension: How to Remove Tree Stumps
Written by Cincinnati Stump Grinding and checked against the sources above on October 26, 2026. City rules and product guidance change, so check the linked page before you act.