Structural soils can support both impervious and porous paving in a variety of applications, including sidewalks, driveways, low-use access roads, parking lots, and pedestrian courtyards. The specialized soils encourage deep rooting, which reduces the heaving of sidewalks, driveways, and curbs by tree roots. The depth of the structural soil impacts its ability to support large tree growth, with a 24-inch to 36-inch (61-91 cm) depth being optimum (Haffner and Bassuk 2007).
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