Multiply the diameter of the tree by eight. That’s the minimum distance from the trunk you can cut with low risk of serious harm. [3] X Research source Cut roots on one side of the tree only, especially if you’re risking a cut closer than the minimum distance.
Galvanized metal roofing. Fold the top over to avoid a dangerous sharp edge. [5] X Research source A double layer of HDPE plastic,Overlap sections of barrier by at least 12" (30 cm) so roots can’t slip through. sometimes available free from feed stores[6] X Research source For best results, buy a commercial root barrier treated with herbicide. Trifluralin is a common option unlikely to harm nearby plants. [7] X Research source
If you’ve cut down the main tree but suckers are still appearing in your yard, your only option may be to apply a broadleaf herbicide. This will kill all vegetation in the area. Repeat each time suckers appear until the roots run out of nutrients. [9] X Research source
Carefully remove any damaged concrete with minimal damage to roots. Cover the area with geotextile fabric. Leave 6" (15 cm) of clear ground around the trunk, or 12" (30 cm) for large trees. [10] X Research source Cover with 3–4" (7. 5–10 cm) of crusher run (a type of crushed stone aggregate) or 6–8" (15–20 cm) of coarse mulch. Mulch is less effective, and may wash away in rain. Edge the material with stones to minimize shifting.
Some herbicides are toxic to fish or other wildlife. The label should describe the environmental impact, and may include information on how to minimize it. For best results, hire a professional plumber to apply metam-sodium. This is a corrosive chemical that requires training and safety equipment to use.
You may also need to remove or relocate any large trees near the pipe, or the roots will keep growing into the sewer pipe.
Elms, cherries, plums, and lilac trees can regenerate from roots after the trunk is damaged. [13] X Trustworthy Source Royal Horticultural Society Leading gardening charity in the U. K. providing resources for identifying, growing and caring for flowers and other plants Go to source Use herbicides instead. Aspens, poplars, sumac, and black locust form “clonal colonies” of many trunks during normal growth. [14] X Research source Their roots are very difficult to control even with herbicides. [15] X Research source A local agricultural extension can recommend an effective herbicide treatment for your species.
Before taking a chainsaw to a root, place a board underneath it. This protects the chainsaw from dirt and rocks. Once you’ve made some progress on the hole, spray the area with a hose or pressure washer to reveal more roots. [17] X Research source
Clear away any rocks near the stump that could damage the grinding wheel. Position the wheel a few inches above the stump’s front edge. Start spinning the wheel, then lower it slowly about 3 inches (7. 5 cm) into the stump. Slowly move the wheel from side to side to cut away wood to a 4 inch (10 cm) depth. Repeat with the next section of stump until it is level. Repeat the process until the whole stump is ground at least 8–10 inches (20–25 cm) below the ground, or deeper if you want to plant a new tree. [19] X Trustworthy Source Royal Horticultural Society Leading gardening charity in the U. K. providing resources for identifying, growing and caring for flowers and other plants Go to source
Triclopyr amine should work at concentrations of 8. 8%. [24] X Trustworthy Source EDIS Electronic database of the University of Florida Institute of Food and Agricultural Sciences’s peer-reviewed articles Go to source For glyphosate, try to find a concentration of about 40%, then dilute with an equal amount of water. If that isn’t available, apply undiluted product with at least 20% concentration. [25] X Research source Herbicides containing 2,4-D, dicamba, or picloram are risky, as they may spread to nearby vegetation and kill it as well. This shouldn’t happen with careful application of glyphosate or triclopyr. [26] X Research source
You do not need to wear a mask, since you will not be spraying herbicide into the air.
Cut the stump close to the ground. Keep it as level as possible, so herbicide doesn’t run off into the ground. Clear away sawdust. Using an old paintbrush, apply herbicide just inside the bark ring. This is where the living tissue is that will carry the herbicide to the roots. Dispose of the paintbrush and empty herbicide containers at a hazardous waste center. [30] X Research source
Chop downward into the trunk at a 45º angle to make a wedge. Insert a spray bottle with a narrow nozzle directly into the wedge. Squeeze in a little herbicide, trying not to get any outside of the cut. Consult your herbicide label to find out how many cuts to make, and how much herbicide to place in each cut (usually 1 mL or less). Some extra-aggressive trees require girdling instead, with herbicide applied to the freshly exposed wood. [32] X Research source
Some trees or root systems may require multiple coats of herbicide to fully penetrate the wood. If the tree survives, check your herbicide label for multiple application instructions. Expose a fresh layer of wood with each application.
