To better understand root conflicts, it is necessary to explore how roots develop and expand over time. Tree roots are active, opportunistic extensions of the tree that provide support and supply water, oxygen, and nutrients needed to feed the tree and sustain its life. The woody transport roots increase regularly in diameter, and even display annual rings. It is this increase in size that swells the base of trees and raises the earth around them often exposing surface roots . If a tree's roots are in a crowded location, the roots can also lift sidewalks .
Roots can also invade broken sewer lines, causing slow draining sinks and sluggish toilets.
For all of the above reasons and more, it is necessary to plan to avoid future conflicts. It is important to follow correct planting requirements . Roots can be damaged in a number of ways. Extremes of heat and cold, drying, and frost heaving in the upper layers of soil can kill many of the delicate, non-woody feeder roots. Foraging by nematodes and other soil creatures, as well as digging by humans, can take their toll on roots.