How to Level Ground After Tree Removal

The mistake almost everyone makes is doing it once. You fill the hole, lay sod, and eight months later there is a dip where the tree used to be, because the wood underground carried on rotting after you stopped paying attention.

Plan for two passes and you will only do it twice instead of four times.

The order

1. Take the chips out. All of them, if this is going back to lawn. They are useful elsewhere in the garden, just not here.
2. Check the depth. You want the ground clear of wood to 8 to 12 inches down. If the grinding stopped at four inches, you will be filling a sinking hole for years and the only real fix is to grind it deeper.
3. Fill with topsoil. Screened topsoil, not builder’s fill and not garden compost, which decomposes further and drops again. A 24-inch stump hole typically takes a third to a half a cubic yard.
4. Overfill by two to three inches. Deliberately. Mound it above the surrounding grade, because it is going to settle.
5. Water it in. Soak it properly and let it settle for a week or two rather than tamping it hard, which on Austin clay just creates a compacted plug that drains badly.
6. Top up, then plant. Come back after the settling, level it off, and then seed or sod.

Why it keeps sinking

Two things are happening. The soil you added is settling into air gaps, which is over within weeks. And the root system left in the ground is decaying, which takes three to ten years depending on species. Live oak and pecan roots are slow; hackberry and Arizona ash go faster.

That second process means a gradual drop over the first couple of years no matter how well you do the first fill. Expect to add a bag of topsoil once or twice. That is normal and it is not a sign anything went wrong.

Austin clay, specifically

East of I-35 you are filling a hole in Blackland Prairie clay, which shrinks and swells with the seasons anyway. Two things follow.

Do not backfill with pure sand or pure compost surrounded by clay, because you create a bowl that collects water and drowns whatever you plant. Use topsoil close in character to the ground around it.

And do the job in autumn or spring rather than the middle of August. Filling and levelling in the worst heat means watering a bare patch daily, and new grass has almost no chance.

West of I-35, over limestone, the hole is often shallower to begin with and settles less. You may need less soil than you expect.

Grass over the spot

Sod can go down as soon as the fill has settled and you have topped it level, so realistically two to three weeks after grinding. Seed is slower and needs the soil temperature to be right, which for St. Augustine and Bermuda in Austin means late spring through early summer.

Whichever you use, keep wood chips out of the top few inches. Grass roots in a chip layer stay yellow and thin and you will be back to it.

Planting a new tree there

Wait about a year, and plant three to four feet to one side rather than in the same hole. The remaining root mass ties up nitrogen as it decays, and settling ground is a poor place for a young root system to establish.

If you want a tree in exactly that position, it needs grinding to 18 inches or more and the old material genuinely removed, which costs more and is worth saying at the time of the removal rather than afterwards. See what stump grinding costs and what happens to the roots.