Sap

Sap, in botany, the watery fluid in the stems and roots of plants. There are two kinds of sap. One consists of water and dissolved minerals and travels from the roots of the tree to the leaves, moving through a layer in the stem and trunk called the xylem. The other consists of water carrying dissolved plant foods, moving from the leaves to other parts of the plant for storage. It passes through a layer called the phloem.