Old roots and stumps are an unwanted addition to some homes and gardens. When you tear out or cut down a tree, you are left with the stump or roots of the tree, and you may even discover that the tree keeps growing. Before you start worrying about hiring an expensive professional to remove the remnants of the tree, use rock salt to kill those roots or stump.
Combine one part rock salt with one part warm water in a large bucket and mix until the salt dissolves. Rock salt is considered any type of rock with large crystals and includes Epsom salt. You can also use kosher salt if you can’t find traditional rock salt.
Identify the areas of your yard where you want to use the rock salt. You want to be careful because the combination can actually kill other flowers, vegetation and trees in the surrounding areas. The best way to avoid this is by carefully locating the roots and stumps ahead of time.
Drill holes around the base of the stump using a large drill bit and an electric drill. This allows the rock salt to thoroughly coat the inside of the stump and kill it from the inside. You can also try drilling into the roots and digging a few holes in the dirt to reach hidden roots.
Pour the rock salt and water combination directly into the stump through the holes you drilled earlier. Keep pouring the rock salt into the holes until you see it coming out the top or sides. Then pour the mixture on top of the roots and onto the ground directly above the roots.
Treat the roots or stumps once a week, for at least four weeks, to kill the roots and stumps. You can add more rock salt and water to the area several times a day, but only if the mixture is absorbed. The roots should die within four weeks; if not, you may need to apply treatment for up to six weeks.
Another way to kill stumps with rock salt is to drill holes in the base of the stump and pour solid salt into the holes, without mixing it in water. The salt slowly melts into the stump and spreads through the tree, killing it from within, but it typically takes longer than using the salt and water mixture.
Salt will render soil infertile for several years, so be careful where you apply the formula.