Fatörzs

Fatörzs, also known as the tree trunk, refers to the main woody axis of a tree, extending from the base to the crown. It provides mechanical support for the canopy and serves as the primary conduit for water, minerals, and photosynthates between roots and leaves. The trunk consists of three tissue systems: the outer bark, the vascular cambium, and the inner wood. The phloem, located just inside the bark, transports sugars from the leaves to other parts of the tree. The xylem, which makes up the bulk of the trunk, conducts water and dissolved minerals upward from the roots. The xylem differentiates into sapwood, which is actively conducting, and heartwood, which is older and typically non-conductive but contributes to strength.

In temperate species, growth in the trunk occurs in annual rings, produced by the cambium as it generates new xylem toward the inside and new phloem toward the outside. The width and pattern of rings reflect growing conditions and age and are used in dendrochronology. The trunk diameter at breast height (DBH) is a common forestry measurement, and trunk taper and buttressing at the base may affect stability and usability.

Trunk health is critical for overall tree vitality. Damage from fire, pests, or disease can impair transport and structural integrity. The fatörzs is a central feature in forestry, ecology, and tree biology.