Aloe Gardens

Aloes are extraordinarily diverse in habit, including small, creeping succulents, grass-like plants, shrubs, small trees, and even species that produce bulbs. Aloe ferox, the bitter aloe, is used as the symbol for the UCI Arboretum. This species has a long history of pharmaceutical use, primarily as a laxative. In Africa, it was used to paint children's' fingernails as a means of discouraging thumb sucking. The Arboretum maintains a number of extremely rare Aloe species, including Aloe pillansii, Aloe susannae (from Madagascar), and Aloe dichotoma, the quiver tree. The quiver trees growing now at the Arboretum are about 20 years old. They were grown from a plant that produced a few flowers while declining after being transplanted. Because aloes are self-sterile, the flowers produced by this dying plant were pollinated with pollen obtained from Huntington Botanical Garden (in Africa, sunbirds transfer pollen; in southern California, hummingbirds often seem to be effective pollinators, although not between the Huntington Botanical Garden and the UCI Arboretum). Native people in Africa use Aloe arborescens, a species commonly planted in southern California, as a living corral: individuals are planted in large circles, broken only by a wooden gate used to move livestock in and out of the corral. The large spines on the leaves discourage escape of livestock, or intrusions by predators. Use of a living fence is ingenious, especially in a habitat where there is little wood for building fences.