Trees get into trouble when they become low on energy reserves, when their roots can’t get enough oxygen or water, or when more than 40% of their root system is lost. Most construction damage happens to the root system. Developing a site is seldom possible without hurting tree roots to some extent. Roots are one of the most vital parts of the tree, responsible for nutrient, oxygen and water uptake and anchoring the tree in the soil. In addition, energy-rich chemicals are stored in the roots. Trees draw on these energy reserves to get them through emergencies like drought, defoliation, insect attack or construction damage.