Answer: Tree roots are categorized into 3 growing habits: Tap root (hickory, walnut, butternut, white oak, hornbeam); Heart root (red oak, honey locust, basswood, sycamore, pines); Flat root ((birch, fir, spruce, sugar maple, cottonwood, silver maple, hackberry). If you want a tree with a narrow root system, you can choose from hickory, walnut, butternut, white oak or hornbeam. These trees have a narrow, deep rooting system. Next choices are oak, honey locust, basswood, sycamore and pines. These trees have a deep root system that extends out as far as the branches on the canopy. Good shade trees in the tap root category are walnut, white oak and hornbeam.
Best wishes with your new trees.
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