Tree roots seek out the moisture and nutrients necessary for survival, but this growth can lead to significant problems when roots encounter human infrastructure. Roots commonly infiltrate underground plumbing systems, causing costly damage, or they can crack foundations and lift driveways. The method for effective root removal varies greatly depending on the root’s location, size, and whether the goal is to fully remove the root or simply kill it in place.
Mechanical Root Removal Methods
Physically removing accessible tree roots is the most direct approach for surface roots or those near a foundation. Roots less than one inch in diameter can usually be cut cleanly with hand tools such as loppers or a sharp pruning saw.
For larger, more stubborn roots, an axe, root saw, or electric reciprocating saw may be required to sever the root mass from the main stump. If the entire stump and its attached roots are the target, a heavy-duty stump grinder will mechanically chew the wood down several inches below ground level. Cutting major structural roots—those greater than three inches in diameter—can compromise the tree’s stability and health, requiring a professional arborist’s risk assessment.
Chemical and Natural Root Killing Agents
When a root is inaccessible or the goal is to prevent regrowth from a remaining stump, chemical and natural agents can kill the tissue. A common non-chemical method uses a high concentration of salt, such as Epsom salt (magnesium sulfate) or rock salt (sodium chloride), to dehydrate the root cells. This is applied by drilling multiple deep holes into the stump or exposed roots, filling them with salt, and moistening the area to dissolve it.
For faster results, commercial stump killers containing herbicides like Triclopyr or 2,4-D amine can be applied directly to the fresh-cut surface of the stump. The herbicide is absorbed by the vascular system, traveling down to the root tips to kill the remaining structure. These methods, particularly rock salt, can increase soil salinity and potentially harm surrounding plants through root grafting or soil contamination.
Specialized Treatment for Sewer Line Roots
Tree roots are attracted to the moisture and nutrient-rich environment inside sewer pipes, entering through tiny cracks or loose joints. Addressing this issue begins with a professional camera inspection to diagnose the location and severity of the root intrusion. Immediate mechanical removal is achieved using hydro-jetting, which employs highly pressurized water streams, sometimes up to 4,000 PSI, to scour the pipe walls and slice through the root mass.
For less severe intrusions, or as a follow-up to mechanical clearing, chemical treatments designed for plumbing systems are used. Foaming root killers contain herbicides like Dichlobenil that expand into a foam, filling the entire pipe diameter to coat all roots thoroughly. This foaming action ensures the herbicide contacts roots growing from the top of the pipe, which liquid treatments often miss, and prevents regrowth for several months. Copper sulfate crystals are a traditional, affordable option that dissolves on contact to kill roots quickly, but they can be less effective at coating the pipe’s upper surfaces and may harm septic systems by disrupting beneficial bacteria.
Preventing Future Root Problems
Proactive planning is the most effective strategy for avoiding future conflicts between roots and infrastructure. When planting new trees, selecting non-invasive species, such as dogwoods or magnolias, reduces the risk of extensive root spread. Trees should be planted at least 10 to 20 feet away from foundations, driveways, and underground utility lines.
For existing trees near vulnerable areas, installing root barriers can redirect growth. Physical root barriers are rigid materials, like plastic or fiberglass, buried vertically to a depth of 24 to 36 inches to force roots downward and away from structures. Chemical barriers use slow-releasing root-repellent compounds to discourage root growth in specific zones, mitigating future damage without full root excavation.