A taproot is a primary root that grows vertically downward and gives off small lateral roots. It is the main root of a plant that has a taproot system. Some plants use their taproots as storage organs for food or water.
Trees are plants that have taproots, but not all trees have the same type of taproot. Some trees have a persistent taproot that remains dominant throughout their life, while others have a transient taproot that is replaced by a fibrous root system after a few years. The type of taproot depends on the species of the tree and the soil conditions.
Some examples of trees that have persistent taproots are oaks, elms, pines and firs. Some examples of trees that have transient taproots are maples, birches, willows and poplars.