Maple trees belong to the Acer family. Myriad species of maple thrive in the United States including ubiquitous red and silver maples as well as their well-known relative, the sugar maple. While some maples, like the bigleaf, grow 100 feet tall, most do not grow the deep roots associated with tall trees. Instead, they run surface roots that prove problematic to homeowners.
Maples are deciduous trees, losing their leaves in the winter. Much of their appeal comes from their deep-lobed leaves that provide vivid colour in autumn. Although some species bear small leaves, other maple leaves reach 15 inches across. Maple tree height varies by species, ranging from shrub presentation to towering trees with 60-foot crowns. Maple roots adjust and adapt to their terrain but are generally strong and shallow.
Although some maples, like the sugar maple, develop deep, spreading roots in fertile soil, most members of the Acer family keep the bulk of their roots close to the surface of the soil. Maples anchor themselves with central taproots, but direct most of their roots horizontally some 4 to 8 inches under the surface of the soil. Maple roots grow fast, and, as they enlarge over time, the roots often break through and protrude above ground.
Homeowners view surface roots as unsightly and destructive, but the adaptation provides many benefits to a tree in the wild. A maple's surface roots give it a competitive advantage over other plants for available nutrients and water. Surface roots also aid trees to survive droughts by trapping moisture from the slightest rainfall. For the many species of maple that cluster on river banks, shallow roots prove essential to flood survival. When rivers flood, trees with roots close to the soil surface obtain oxygen fastest when water recedes.
The same shallow root system that helps maples thrive in the wild creates problems in backyards. Strong surface roots clog or damage sewer systems, crack and tilt sidewalks and enter drain lines. When a maple's thick roots appear in the middle of a lawn or driveway, a homeowner's choices are limited. He must either accept the unsightly roots or else risk killing the tree by removing them. Wise gardeners research a tree's root system before planting.