Avoid tree root conflicts

Roots erupting through the soil surface beyond the tree trunk irritate gardeners when trying to grow and mow grass under trees. Save time, reduce frustration and be kind to your trees when dealing with these surface roots. These roots are a normal part of aging for shallow rooted trees and are important to their health and stability.

As roots age, they increase in circumference just like the tree’s branches and trunk. The upper portion of the roots even­tually appear above the soil surface. Covering the roots with soil is only a temporary solu­tion and adding too much, even a couple inches, can be detri­mental to the health of the tree. Your tree may look fine the first few years after installing that raised planting bed, but eventu­ally the tree’s leaves get smaller and drop earlier in the fall. And after five or ten years the tree may even die.

Do not cut, dig up or shave off these important roots. Damag­ing the roots creates entryways for insects and diseases to move in and cause trees to decline and possibly shorten their life.

Mulch is a simple solution. Use a 2-to-4-inch layer of or­ganic mulch like leaves, ever­green needles and woodchips on the soil surface surrounding the tree. The finer the mulch mate­rial the thinner the layer need­ed. Apply the mulch throughout the area under the tree’s drip­line, if possible, or in a circle extending at least 3 feet all the way around the tree. Pull the mulch away from the tree trunk to avoid insect, disease and ro­dent problems.

Eliminating grass and cover­ing the soil with mulch is also better for the tree and less work for you in the long run. Grass competes with the tree for wa­ter and nutrients and as you may have discovered, growing grass in the shade of some trees can be challenging. You also eliminate the need to hand trim grass growing near the tree, saving you time while protect­ing your tree from weed whip and mower damage.

Consider shade-tolerant pe­rennials and groundcovers if mulched beds do not fit your design style. These plants elimi­nate the need to mow over sur­face roots. They are less com­petitive than lawn grass, pro­tect the soil from erosion, help manage storm water and add seasonal interest to your land­ scape.

Select plants suited to the growing conditions and hardy for your climate. Use caution when planting under mature trees. Avoid deep tilling that can damage not only the surface roots, but also the fine feeder roots that absorb water and nu­trients. Instead, dig relatively small holes between major roots and allow the plants to fill in the area.

Mulch the soil surfaces around these groundcover plants with leaves, evergreen needles or other organic mulch. Water thoroughly once the plants are in the ground and of­ten enough to keep their roots slightly moist throughout the summer. Gradually extend the time between watering to en­courage the plants to develop a robust root system.

Invest a bit of time now to re­duce ongoing maintenance, im­prove the health of your trees, and add beauty to your land­scape.

Melinda Myers’ website is www.MelindaMyers.com.