Root composition refers to the spatial shape and geometric distribution of various types of roots or random roots in the same root system in the environment. It can be divided into solid geometry and planar geometry. In the traditional sense, three-dimensional geometric composition consists of two categories. Important indicators describing the direct root and root systems of the fibers and the solid geometry of the root system include fractal geometric parameters, such as the angles between the main lateral roots and the angles between the roots of the fiber.