The Complete Guide to Stump Grinding

After a tree comes down, the stump remains. It sits in your yard like a stubborn reminder of what used to be there, slowly collecting moss, sending up suckers, and making mowing awkward. Stump grinding is the most practical way to deal with it. Here is everything you need to know about the process, from how it works to what your yard will look like afterward.

How Stump Grinding Works

A stump grinder is a machine with a rotating disc or wheel fitted with carbide-tipped cutting teeth. The operator positions the wheel against the stump and sweeps it back and forth, grinding the wood into small chips. The machine works its way across the entire surface of the stump, gradually lowering it below grade.

Most residential stump grinding goes 15 to 25 centimetres below the surrounding soil level. This is deep enough to cover the area with soil and grow grass over it, or to plant a garden bed. If you plan to pour concrete, install pavers, or build a structure over the location, you may want the grind to go deeper — 30 centimetres or more — to ensure stable footing.

The process produces a large volume of wood chips — roughly five to eight times the volume of the stump itself, because the wood is shredded rather than compressed. These chips are typically used to backfill the hole, with the excess either spread on site or hauled away.

Stump Grinding vs. Stump Removal

These two terms are often confused, but they describe different processes:

• Stump grinding: Grinds the stump and surface roots below grade. The root system remains in the ground and decomposes naturally over several years. This is the standard approach for most residential situations.
• Stump removal (excavation): Digs out the entire stump and major root system using an excavator or backhoe. This is more disruptive, more expensive, and leaves a much larger hole to fill. It is typically only necessary when building a foundation or doing significant hardscape work directly over the stump location.

For the vast majority of Calgary homeowners, grinding is the right choice. It is faster, less expensive, and causes far less disturbance to the surrounding landscape.

What About the Roots?

After grinding, the roots remain underground. They will decompose naturally over three to seven years, depending on the species, root size, and soil conditions. As they break down, the soil above them may settle slightly, creating minor depressions that can be topped up with soil.

Some species — poplar, elm, and Manitoba maple in particular — may send up root suckers after the stump is ground. These are shoots from surviving roots that attempt to grow into new trees. Mowing them down regularly will eventually exhaust the root's energy reserves. Persistent suckers can be treated with a targeted herbicide application, but this should be done carefully to avoid affecting nearby plants.

Can You Do It Yourself?

Rental stump grinders are available from equipment rental companies in Calgary, and the prospect of saving money by doing it yourself is tempting. However, there are good reasons to think twice:

• Safety: Stump grinders are powerful machines that throw debris at high speed. Rocks, metal fragments (old nails, fence hardware), and wood chips can become projectiles. Proper safety equipment — face shield, hearing protection, steel-toed boots, and chaps — is essential.
• Utility lines: Before grinding, you need to call Alberta One-Call (1-800-242-3447) to have underground utilities located. Gas lines, water lines, telecommunications cables, and electrical conduits can all run through a yard, sometimes just a few inches below grade. A professional knows how to work safely around located utilities.
• Machine size: Rental grinders are typically smaller units that struggle with large stumps. A stump from a mature elm or spruce can be 60 to 90 centimetres across, and a small rental grinder may take hours to process what a commercial machine handles in 30 minutes.
• Access: Getting the machine to the stump requires navigating gates, fences, gardens, and potentially the neighbour's yard. Professional crews have experience manoeuvring equipment through tight spaces without causing collateral damage.

What It Costs

Stump grinding pricing in Calgary is typically based on the diameter of the stump, measured at ground level. For a standard residential stump, expect to pay between $150 and $500, with most stumps falling in the $200 to $350 range. Factors that affect pricing include:

• Stump diameter — larger stumps take longer and cost more.
• Access — difficult access (narrow gates, long carries, steep slopes) adds to the cost.
• Number of stumps — multiple stumps on the same visit are usually discounted per stump.
• Depth of grind — deeper grinds take more time.
• Root grinding — surface roots that extend beyond the stump can be ground as well, but this adds to the scope.

After the Grind

Once the stump is ground, you are left with a hole filled with wood chips. If you want to grow grass, rake out the excess chips, add a layer of quality topsoil (10 to 15 centimetres deep), and seed or sod. If you plan to plant a new tree, shift the planting location at least a metre from the old stump — the decomposing chips tie up nitrogen and can stress a new tree planted directly on top.

Expect the filled area to settle over the next six to twelve months. Top it up as needed. Within a year or two, you will not be able to tell a tree ever stood there.