The bark includes all the tissues outside the secondary phloem, i.e., pericycle, cortex, periderm and all dead cells external to periderm. Sometimes an addition-al layer of periderm is formed in the region of phloem so that all the tissues lying outside because dead. Under such conditions, all the dead tissues outside the active periderm (i. e., pericvclo, cortex and external periderm) are; considered as bark.
