Cambium:

♤ The thin layer of living cells just inside the bark is called cambium.

♤ It is the part of the tree that makes new cells allowing the tree to grow wider each year.

Sapwood (Xylem):

♤ The scientific name for sapwood is xylem.

♤ It is made up of a network of living cells that bring water and nutrients up from the roots to the branches, twigs and leaves.

♤ It is the youngest wood of the tree -- over the years, the inner layers of sapwood die and become heartwood.