You’re trying to figure out if stump grinding is actually going to solve your problem or just take the top off and leave everything else. You want to sod over it, maybe put a garden bed there, and you need to know if what’s left underground is going to cause issues.
Here’s what grinding actually does and how deep it goes.
The Standard Depth Is 6 to 12 Inches Below Grade
Most stump grinding goes 6 to 12 inches below the surface of the ground. That’s enough to get the main stump and the surface root flare well below grade so the area can be filled, leveled and used for whatever you have planned.
For most residential situations in Spring Hill that depth is sufficient. You can sod over it, put down landscaping, pour a concrete pad or build a garden bed without the remnants of the stump causing problems. The grinding goes deep enough that nothing is going to push back up through whatever you put over it.
What Affects How Deep the Grinding Goes?
The size of the stump is one factor. A larger stump with more material to work through takes longer and the operator works through it more thoroughly. The type of equipment matters too. Commercial grade grinders used by professional crews go deeper and work faster than the rental units homeowners sometimes try to use themselves.
The specific request matters as well. If you tell the crew you’re planning to sod or landscape over the area they’ll grind deeper to make sure you have a clean base to work with. If you just want the visible stump gone and aren’t doing anything specific with the area they may not go as deep. Be specific about what you’re planning to do with the spot so the crew grinds to the right depth for your situation.
What’s Left Below the Grinding Depth?
The major structural roots that spread out from the tree underground stay in the ground. Grinding addresses the stump itself and the surface root flare but it doesn’t follow every root that extended out from the tree. Those deeper roots are left to break down on their own over time.
This is not a problem for most situations. Dead roots don’t grow and they break down naturally. The soil above them is fine for sod and most landscaping. Where it can matter is if you’re planning something that requires undisturbed soil at depth, like a footing or a retaining wall, in which case you’d want to know where the major roots ran before you start digging.
Is There a Way To Get It Deeper?
Yes. You can ask the crew to grind deeper than standard if your project requires it. Going deeper takes more time and typically costs more but it’s a reasonable request for situations where you need the ground completely clear of stump material to a greater depth.
If you’re planning to put in a new tree in the same spot going deeper is worth considering. Getting more of the old stump material out reduces competition for the new roots and lowers the risk of any residual disease in the old wood affecting the new tree.
What About the Wood Chips Left Behind?
After grinding the depression is filled with a mix of wood chips and ground root material. That material is not ideal as a growing medium on its own because it pulls nitrogen from the soil as it breaks down. For sodding or planting you want to rake out as much of the chip material as you can and replace it with good topsoil before laying sod or planting.
How much of the chips you need to remove depends on what you’re doing with the area. For sod getting the bulk of the chips out and filling with topsoil is the right approach. For a garden bed where you’re going to be amending the soil anyway a complete chip removal is less critical.
If you want to know exactly how deep the grinding will go for your specific stump and what that means for what you’re planning to do with the area, talk to a stump grinding crew before you commit to anything. Spring Hill Tree Specialists offers free estimates on all work.