Acacia koa has this kind of symbiosis which doubtless has significant ecological importance. Most species have mychorrizal associations with soil fungi . These are very important for the absorption of water and minerals from soil. Large tropical trees may have root buttresses at the base. These help to support the large aerial portions of the tree.
Vines have roots which cling to aerial structures.
The Stems of Dicots are very similar to those of the Coniferophyta. They have Multicellular Apical Meristems and Lateral Branching . They have a Eustele and an Ectophloic Siphonostele . The Vascular Bundles in an Atactostele are organized into more than one ring and they can usually be found at the center of the stem. Take BOT 410 to learn more about this.