They have two leaf types, with palmately lobed juvenile leaves on creeping and climbing stems, and unlobed cordate adult leaves on fertile flowering stems exposed to full sun, usually high in the crowns of trees or the top of rock faces. The juvenile and adult shoots also differ, the former being slender, flexible and scrambling or climbing with small roots to affix the shoot to the substrate (rock or tree bark), the latter thicker, self-supporting, and without roots. The flowers are produced in late autumn, individually small, in 3–5 cm diameter umbels, greenish-yellow, and very rich in nectar, an important late food source for bees and other insects; the fruit are small black berries ripening in late winter, and are an important food for many birds, though poisonous to humans. The seeds are dispersed by birds eating the fruit. The leaves are eaten by the larvae of some species of Lepidoptera such as Angle Shades, Lesser Broad-bordered Yellow Underwing, Scalloped Hazel, Small Angle Shades, Small Dusty Wave (which feeds exclusively on ivy), Swallow-tailed Moth and Willow Beauty.