1. the outer layer of bark in woody plants, consisting of dead cork cells
Usage: botanical

Examples

• The phellem protects the tree from water loss and physical damage.
• Cork oak trees have thick phellem that can be harvested commercially.
• The botanist examined the phellem under a microscope to study its cellular structure.
• As the tree ages, its phellem becomes thicker and more protective.
• The phellem layer prevents pathogens from entering the inner bark.
• Wine corks are made from the phellem of cork oak trees.