The increment of secondary xylem produced in any one growing period in the stems and roots of many plants, especially those in temperate regions. In transverse section this is visible as a ring and is due to the difference in radial diameter of xylem elements formed at the beginning and end of the growing season. There may be one or several growth rings in any one year, i.e. an * annual ring may consist of more than one growth ring. The growth rings are then termed false annual rings. See also dendrochronology. |
