Tree roots growing at or slightly above the soil surface are called surface roots.
- Surface roots can make it difficult to mow the lawn or grow grass.
- When trees and grass compete for moisture and nutrients, the tree roots usually win.
- Grass growing over or near the surface roots may become thin and paler green than the surrounding lawn.
- Many tree species have a shallow root system and are prone to surface roots. Tree species prone to surface roots are maple, sycamore, willow oak, pin oak, lindens, and black walnut.
- Any tree can develop surface roots in heavy, compacted soil, wet soils, or as a result of erosion.
- If surface roots develop as a result of erosion, adding soil and planting grass seed may help. Because these roots require oxygen, no more than 1-2" of soil should be added around the root system. Severely eroded areas may need more to raise the soil to its original level.
- If surface roots are not due to erosion, adding soil is only a short-term solution. The tree may develop new roots in the additional soil.
- Where dense shade and surface roots make it impossible to grow grass successfully, planting groundcover or a mulch ring around the tree may be the best solution.
- It is not advisable to remove surface roots.