Q: I had a tree in my lawn that is now gone. The stump rotted and a large hole appeared. Can I use some leftover thinset mortar mix in the bottom part of the hole?

A: I don’t foresee any problems as long as the top of the concrete filler material is more than six inches below ground level. Grass roots only extend six inches into the ground, so anything deeper than that isn’t problematic. You could also fill the bottom of the hole with compacted clay soil.