The tree trunk is the central stem of a tree that supports the branches and leaves It is made up of several layers including the bark cambium phloem xylem and heartwood The bark serves as protection against external elements while the cambium is responsible for the growth of the tree The phloem transports nutrients and water while the xylem helps in the transportation of water from the roots to the leaves The heartwood provides structural support and strength The trunk can vary in size and texture depending on the type of tree and its age A strong trunk allows the tree to withstand various weather conditions and support the weight of its branches and leaves