It is usually from the xylem sap of sugar maple, red maple or black maple trees that maple syrup is made from although it not limited to those maple species.
These trees, in cold climates, store starch in their trunks and in their roots. In the spring, the starch is then converted to sugar that rises in the sap. The maple trees are then tapped by boring holes into their trunks and the released sap is collected. After the sap is collected, it is processed by heating to evaporate much of the water, leaving the concentrated syrup.