A tree vitality requires a complex process consisting in transformation of natural ressource. In other words, the tree's extract from the soil and the air, the elements they need and with the energy of the sun, it transform and devellop these ressource into food. Trees are mainly composed of three parts; the roots, the trunk and branches and the foliage (leaves or needles).  RootsThe roots are usualy the hidden part of the tree as they are primarly underground. They are destinate to play four roles in the tree vitality. They anchor the tree solidly in the ground, they absorb and transport water and minerals and they store the food processed by the leaves. In younger tree's, the root system is composed of a sole main root, called the tap root. As the tree gets older, it will develop a lateral network of roots terminating with fine 'roots hair'. These small roots, are the ones that absorb water and minerals. Food storage is necessary for next seasons production of leaves, seeds and flowers.Trunk and branchesThe trunk and branches also play different functions. They are the distributor of the water and mineral of from the roots to the leaves but they return the processed food back to the roots from the leaves. They also are a flexible support for the canopy. They are composed of four main sections. First, the Bark, wich protect the inner tree sections from insects, injury and prevent dryness. The second part is the cambium. It is a small layer of tissue compose with multiple cells that reproduce themself constantly which help the tree gain girth. It is also this layer that will form a protective skin again an injury before recreating bark. Third, the layer of sapwood. This layer is the highway for food, minerals and water. It act as the canal between the roots and the leaves for a back and forth distribution of goods. Fourth and last is the heartwood. It is composed of dead wood and is normally darker in color because of the higher resin concentration. LeavesThe leaves are the factory of the vitality process. They transform the natural elements into food, with the help of the ligth/sun, a process called photosynthesis. The leaves also absorb carbon dioxide from the air to incroporate with water and minerals to form the complex but essential compound for tree survival.