: Oleaster, Silverberry
: Invades disturbed areas, can out-compete native species; increases nitrogen levels to the detriment of native communities; had been widely recommended for conservation planting until invasive traits became apparent.
: Deciduous shrub or small tree growing up to 6 m (20 ft) in height and 9 m (30 ft) wide.
: Simple, alternate, oval, 5-10 cm (2-4 in) long, margins entire and wavy, gray-green above, silvery scaly below; early leaf out (mid-March).
: Often thorny; silvery or golden brown; brownish scales give stems a speckled appearance.
: Fragrant, tubular, 4 petals and stamens, cream to light yellow in color, borne in clusters of 1-8; bloom from April through June.
Fruit and seeds
: Drupe, 0.6 cm (0.25 in), silvery with brown scales when immature, speckled red or yellow when mature; ripen September to October, begin to bear fruit at 3 to 5 years, each tree can produce 2-8 lbs. of seed per year, fruit eaten and seed dispersed by birds.
: Shade tolerant; occurs in a variety of soil types (pH range of 4.8-6.5), thrives on infertile soils because of nitrogen-fixing root nodules; found in open woods, forest edges, roadsides, fence rows, meadows, sand dunes, and other disturbed areas.
: Primarily by seed, also by stump & root sprouting.
: Native silver-berry (E. commutata
) has opposite leaves; non-native Russian olive (E. angustifolia
) has longer, narrower, leaves, silver above and below.
Monitoring and rapid response
: Monitor sunny open sites; autumn olive leafs out early in spring, retains leaves in fall, can be recognized year-round. Hand pull seedlings; focus on newest infestations and highest quality areas first; Cutting, girdling and burning are ineffective without herbicide as they stimulate sprouting; basal bark/stem sprays effective in late spring, possibly in fall; basal stem injection of herbicide on dormant plants provides excellent control with low concentrations of herbicide. This species is difficult to control, research control options thoroughly.
: The Michigan Natural Features Inventory
(MNFI) has partnered with MISIN to provide the information in this fact sheet. Species images and/or information were used with permission from "A Field Identification Guide to Invasive Plants in Michigan's Natural Communities
" and "A Field Guide to Invasive Plants of Aquatic and Wetland Habitats for Michigan