By Celestine Duncan
Autumn olive (Elaeagnus umbellata) and Russian olive (Elaeagnus angustifolia) are invasive, deciduous, woody shrubs or small trees that were introduced for landscaping, soil stabilization, and wildlife food/cover. Both plants became invasive in riparian areas, open forests, lake shores, and abandoned fields. Although the plants share similar habitat, autumn olive is more widespread in the eastern half of the United States, and Russian olive is more prevalent in the West (Figure 1).
Autumn olive is native to China, Japan, and Korea and was introduced to the United States in the 1830s. Russian olive is native to southern Europe and western Asia and was introduced into North America as an ornamental in the early 1900s. In the United States, both plants were actively promoted for wildlife habitat and erosion control in environmentally disturbed areas. Russian olive was also planted extensively in windbreaks in the western U.S. These woody plants spread long distance by birds that ingest seed, or locally by small mammals that gather and stockpile seeds. The two plants share similar growth form and habitat, but differ in leaf shape and size, and berry color. Following are diagnostic characteristics that differentiate the two species.