|I have three young oaks planted in front of my house. Their trunks are aboout 2 1/2 feet from the sidewalk. I fear that the roots will extend and rip up the sidewalk evenually. I read that roots will spread as wide as the tree branches. If I keep the branches trimed so that they don't spread to wide will this in turn keep the roots from spreading?
|Answer from NGA
October 19, 2009
|Good theory, but it won't work. Even though you keep the branches trimmed, the roots will continue to extend outwards as the trunk matures. Oak trees in general are characterized by having a strong tap root when young that transitions to deep lateral roots when older. If you water deeply, the roots should grow down below the sidewalk. Every few years you can do some feeder root pruning by cutting straight down between the sidewalk and the tree trunk to ensure no roots are growing directly beneath the sidewalk. Dig down a good 12" all along the sidewalk to past the length of the canopy branches and things should be fine for many years. Of course the tree trunks will eventually grow over 2 1/2 feet in girth so the trunks may cause problems in the future by impeding traffic on the sidewalk. With this in mind you may decide to move your trees while they are still young.
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