The root of the problem, though, may not be with the tree, but with people's lack of understanding of how trees grow. Roots, in human terms, are aggressive and active most of the year. They don't enter a dormant period as the top of the tree does. They slow activities with changes in the environment, but they're always ready to take advantage of favorable soil conditions. Roots work for a living.
Tree roots grow close to the soil surface.
They require both oxygen and moisture to survive and thrive. Open soil areas, and soil around structures where there is plenty of oxygen and moisture, are ideal homes for roots. If a root survives and is successful in an area, it will start to get bigger around and form thick, woody walls. Many times tree roots become unwelcome guests near foundations, septic fields, sidewalks and driveways. They grow beneath or into materials and, as they expand and grow, they crack and damage poorly engineered structures.