Q. i just planted an 'October Glory' red maple. Is the root system shallow or deep? I've had trouble with roots coming out of the ground on another tree at a different location, and I want to do what I can to avoid this problem.
A. Tree roots are surprisingly shallow. Except for the anchoring roots, most roots (especially those that are used to collect water and nutrients) are all found within four to eight inches of the surface of the soil. And you can't do much about their trajectory. But the red maple, in contrast to silver maple, doesn't usually produce large roots above the ground, although in time almost any old tree could break the surface with its roots.
Since root span is a natural aspect of tree growth, there really isn't too much you can do to direct root growth. Without good roots, the tree will not thrive. Generally speaking, tree roots will exploit weaknesses that already exist in a pipe or foundation underground and can work their way into a small gap and enlarge it over time. The roots would not usually cause the initial damage. Tree roots (or the expanding trunk flare) may lift sidewalks and pavement as the tree grows, so sometimes using a flexible paving to allow the roots to shift below ground is a workable solution to that problem. In the long run, however, it is best to plant a tree whose mature size is suited to the available space rather than try to cope with an overly large tree in the wrong place.
You also won't have to worry quite as much about competition with your 'October Glory' as you do with other maples. Tree roots typically range way beyond the branch spread, sometimes up to twice as wide. And unlike the silver and Norway maples, the red maple doesn't create that truly dense, almost impenetrable surface network of fine roots. It does compete somewhat with plants such as lawn grasses, perennials and shrubs for light, water and nutrients, however, so you'll need to give those plants a little extra attention.
You can take steps over time to plant appropriately below the tree, using undemanding groundcovers other than grass, or maybe even install a permeable patio of stepping stones or gravel and adding large planters for colorful annuals.
Good luck with your tree!
