The development of a lateral root begins with the formation of a meristematic region in the pericycle. As this grows, the new lateral root pushes out through the endodermis and cortex until it ruptures the surface. The structure of the lateral root is similar to that of the main root. Lateral root initiation in dicots will occur opposite the protoxylem poles. Lateral root initiation in monocots will occur between the protoxylem poles.