To stabilize the soil, engineers compact it to remove as many of the voids as possible. Heavy equipment, designed to maximize the compaction, drives repeatedly over each lift. This activity hurts tree roots by first cutting them, and then by breaking down the soil structure. Location of Tree Roots To protect tree roots from damage, it is important to know where to look for them. Although root systems are often depicted as mirror images of the tops, they usually cover a much larger area.
Roots can extend far beyond the dripline, as much as two to three times the diameter of the crown.
Many trees form vertical sinker roots that arise from larger horizontal roots near the trunk of the tree. Sinker roots aid in water and nutrient absorption from deeper layers of aerated soil during times of drought. Root patterns also are affected by topography and characteristics of the soil or substrate. Trees on slopes tend to have more roots on the downhill side. Roots of trees along streams will parallel the bank.