The structure of vascular cambium is made up of two cells, that is, fusiform initials and ray initials. Fusiform initials are cells that are elongated from the axis and tapered from the ends. The length of these cells varies from taxa and individual plants as well. The fusiform initials increase with the age of the plant. The shape of these cells is similar to flat shoelaces. The ray initials are isodiametric, that is, they have an equal length from all sides. They are smaller in size.