What is lateral meristem and what type of growth does it produce?

Lateral meristem is a type of secondary meristematic tissue located parallel to the sides of organs where it occurs, typically forming cylindrical layers in stems and roots. The two main types are vascular cambium (producing secondary xylem and phloem) and cork cambium or phellogen (producing cork tissue). Unlike apical meristems that cause primary growth (elongation), lateral meristems are responsible for secondary growth, which increases the girth or diameter of stems and roots. This growth is characteristic of woody plants and some herbaceous dicots, resulting in the formation of wood, bark, and the annual rings visible in tree trunks. Lateral meristematic activity allows perennial plants to increase in thickness year after year.