Surface tree roots are a common frustration for homeowners, often creating uneven terrain that makes mowing difficult and poses a tripping hazard. These roots naturally rise toward the soil surface to access oxygen and moisture, especially in compacted lawns where deeper soil is dense. Addressing this issue requires a careful approach to ensure the tree’s health is not compromised while reclaiming the turf area. This article provides safe, actionable methods for evaluating, removing, and managing problematic surface roots.
Evaluating Root Safety and Viability
Before any removal begins, determine if a root can be cut without harming the tree’s stability or long-term health. Trees rely on large structural roots, typically located close to the trunk, for anchorage and support. Removing these anchoring structures can severely destabilize the tree, making it susceptible to wind damage or disease. Smaller, fibrous feeder roots, which primarily absorb water and nutrients, are safer targets for removal as they contribute less to structural integrity.
Roots larger than two to three inches in diameter should not be cut, especially if they originate within a few feet of the trunk. Removing more than 25% of the tree’s total root system circumference can induce significant stress or decline in the canopy.
Chemical solutions, such as rock salt or herbicides, should never be used to kill roots in the lawn. These agents are ineffective for targeted removal and frequently leach into the soil, damaging the entire tree or surrounding vegetation. Chemical root-killing agents are absorbed by living plant tissue and can travel through the vascular system back to the parent tree. This translocation can injure or kill the entire tree over a period of months. Therefore, only mechanical removal of smaller, non-structural roots should be considered, provided the tree’s overall health is good.
Techniques for Physical Root Removal
Once a non-structural feeder root is identified as suitable for removal, physical extraction offers the most immediate solution. Start by carefully excavating the soil around the targeted root to fully expose its path and connection points. Use sharp bypass loppers, a root saw, or heavy-duty pruning shears to ensure a clean cut that minimizes tearing and reduces the risk of disease entry into the remaining root tissue.
Trace the superficial root back to a larger lateral root or the main root structure and make the cut at this junction point. Making the incision flush against the larger root promotes proper compartmentalization of decay in the remaining tissue. Avoid leaving jagged edges or exposed stubs, which can become entry points for pathogens or pests.
The severed root section can then be lifted and removed from the lawn area. For roots too thick for hand tools but within the two-to-three-inch diameter limit, a small, specialized stump grinder can be utilized. This mechanized approach quickly reduces the root material below the soil line, eliminating the surface obstruction.
Operating a stump grinder requires strict adherence to safety protocols, including wearing eye protection, hearing protection, and sturdy footwear. After grinding, the resulting trench should be filled promptly with nutrient-rich topsoil to prepare the area for turf repair. This mechanical technique provides immediate relief from tripping and mowing hazards.
Non-Invasive Landscape Management
For roots deemed structural or too large to remove safely, management strategies that avoid cutting the root system are preferred. One effective method involves adding a thin layer of quality topsoil over the exposed roots to create a new, level growing medium for the lawn. Apply no more than two to three inches of soil to prevent root suffocation, as tree roots require access to atmospheric oxygen for respiration.
Applying a deeper layer of soil can inhibit the gas exchange necessary for root function, leading to the tree’s decline or death due to oxygen deprivation. After lightly mounding the soil, the area can be reseeded using grass varieties known for their tolerance to shade and shallow rooting habits, such as fine fescues or perennial ryegrass. This approach maintains a turf appearance while protecting the exposed roots from mechanical damage.
An alternative technique is to convert the area into a landscape bed, eliminating the need for regular mowing. Covering the root zone with an organic mulch layer hides the roots and retains soil moisture, benefiting the tree by reducing water stress. Shade-loving, shallow-rooted ground covers like hostas, ferns, or vinca can be planted directly in the added mulch or thin layer of topsoil. This non-invasive solution prevents turf maintenance issues without stressing the tree’s established structure.
Post-Removal Lawn Restoration
Once physical root material is removed or topsoil is mounded over the roots, the focus shifts to restoring the lawn surface. The disturbed soil bed must be properly prepared to ensure successful turf establishment and minimize future root protrusion. Begin by lightly aerating the soil to improve drainage and reduce compaction, a common factor that causes roots to seek the surface.
Incorporating organic amendments, such as compost or peat moss, enriches the soil structure and provides necessary nutrients for new grass growth. When reseeding, select a grass blend specifically adapted to the existing conditions, particularly the level of shade cast by the tree canopy. Species like fine fescue, which thrives in low-light environments, or certain shade-tolerant bluegrass cultivars are recommended for these areas.
If sod is chosen, install it promptly and keep it consistently moist during the initial establishment phase to encourage deep rooting. Adequate watering is necessary to help the new grass compete against the tree’s remaining root system for available moisture and nutrients. Maintaining a slightly higher mowing height in these shaded areas can also improve the grass’s vigor and resilience.