The vascular cambium and cork cambium are called lateral meristems because they surround the established stem and make it grow larger in diameter. This is called the secondary growth, giving rise to wood. Full article ...
Phloem is produced in phases. Primary phloem is laid down by the apical meristem. Secondary phloem is laid down by the vascular cambium to the inside of the established layer(s) of phloem. Top Encyclopedia Articles Encyclopedia Index ...