A plant needs roots for two chief reasons: 1. As a means of anchoring itself to the ground. 2. To absorb water and minerals from the soil. The roots of most plants grow in the soil. By elongating their tips, roots are always coming into contact with new portions of soil. Thousands of tiny hairs project from the surface of the young root which absorb the materials from the soil. Types of roots: 1. Some plants have large bulbous roots called taproots. 2. Grasses have fibrous root systems. Soil in which there are many fibrous roots is protected from erosion. 3. Some tropical orchids that grow on trees have spongy roots.