cambium (lateral meristem) A plant tissue consisting of actively dividing cells (see meristem) that is responsible for increasing the girth of the plant, i.e. it causes secondary growth. The two most important cambia are the vascular (or fascicular) cambium and the cork cambium. The vascular cambium occurs in the stem and root; it divides to produce secondary xylem and secondary phloem (new food- and water-conducting tissues). In mature stems the vascular cambium is extended laterally to form a complete ring: the sections of this ring between the vascular bundles comprises the interfascicular cambium. Compare apical meristem.

cambium In botany, layer of cells parallel to the surface of stems and roots of plants. It divides to produce new cells that allow for growth in diameter of the stem and roots. There are two main types of cambium. Vascular cambium produces new phloem on the outside and xylem on the inside, leaving narrow bands of thin-walled cells through which nutrients and gases diffuse to the centre of the plant. Cork cambium forms a cylinder just below the epidermis, and produces cork cells to replace the epidermis, which ruptures as the stem and root expand, forming the bark and corky outer layer of the older root. See also meristem

cambium In the stems and roots of vascular plants, a layer of cells lying between the xylem and phloem. These retain the ability to divide, producing secondary xylem and phloem. This continues throughout the lifetime of woody plants, increasing the girth of the stem. See also BARK.