A fibrous root system is a type of root system that is the opposite of a taproot system. It is usually formed by thin, moderately branching roots growing from the stem. Fibrous root systems are universal in monocotyledonous plants and ferns. The roots are thin, with root hairs, and their function is mainly absorption of plant nutrients and water from soil. Most trees begin life with a taproot, but after one to a few years change to a wide-spreading fibrous root system with mainly horizontal surface roots and only a few vertical, deep anchoring roots. A typical mature tree 30–50 m tall has a root system that extends horizontally in all directions as far as the tree is tall or more, but well over 95% of the roots are in the top 50 cm depth of soil. The fibrous root systems look like a mat made out of roots when the plant has reached full maturity.
Some key features of fibrous root systems include:
- They are composed of large numbers of roots nearly equal in size.
- They do not arise as branches of the primary root but consist of many branching roots that emerge from the base of the stem.
- They are horizontal and wide-spreading with only a few roots that go deep vertically downward.
- They help in fighting soil erosion as they are anchored to the top layer of soil.
Examples of plants with fibrous root systems include grasses, coconut palm, wheat, and rice.
