The two types of vascular bundles areOpen Vascular Bundles: In these types of vascular bundles, cambium tissue is present. It is present in between xylem and phloem elements. The bundles are said to be open. These types of bundles due to the presence of cambium, have the ability to form secondary xylem and phloem in other words, they are capable of secondary growth. As they are open for secondary growth, therefore they are named open vascular bundles. They are present in dicots.Closed Vascular Bundle: The cambium tissue is absent in these types of vascular bundles. The xylem and phloem tissues are joined together and no cambium is present in them. No secondary growth is seen in these types of vascular bundles. Due to this, they are known as closed vascular bundles as they are closed for secondary growth.