Ivy vines are considered to be self-clinging climbers which are not as common. The benefit is they produce short roots from their stems, known as aerial roots, that attach themselves firmly to supports. This way they can attach themselves to completely flat surfaces like walls. They are hardy enough for cool, temperate gardens, especially when compared with the large number that climb by their own means. Hardy, self-clinging species, therefore, have a value of their own, not only for clothing walls and fences, but also for growing up the stems or trunks of suitable trees.