Deciduous plants lose their leaves in autumn by forming an abscission zone at the base of the leaf. Since evergreens retain their leaves through winter, the leaves are adapted to withstand the xerophytic conditions of winter. The site at which a leaf is or was once attached is called a node . The section of stem between nodes is called an internode . The distance between nodes can indicate stress or rapid growth.
Stems provide support for leaves and reproductive structures.
Green stems photosynthesize, and thickened stems function to store either water or carbohydrates. Water and nutrients are moved up from the roots, through the stem in what is termed vascular tissue. Carbohydrates, manufactured in the leaves, are also carried by vascular tissue throughout the plant and may be stored in the roots for use as necessary. In monocots, bundles of vascular tissue are scattered within the soft, non-woody stem. In dicots, the vascular tissue forms a ring.