Autumn olive (Elaeagnus umbettata) and Russian olive (E angustifolia).
Identification: These shrubs or small trees (may grow up to 20 feet) are nitrogen-fixing. Leaves are alternate, oval, 1-3 inches in length, and untoothed. The underside of the dark green leaf is silver in color. Autumn and Russian olives have flowers that are small and light yellow which produce small (< 1/4 inch), round, juicy fruits. The fruits of Autumn olive are reddish to pink and dotted with scales. Fruits are produced in great quantity and persist into winter. In contrast, the fruits of Russian olive are yellow, dry and mealy. The twigs of Autumn olive are usually bronze and silver colored, while the twigs of Russian olive are just silver. The-branches of both are thorny.
Range: Autumn olive was introduced from east Asia (China, Japan, and Korea) in the 1830’s. It is now found from Maine south to Florida, and west to the Great Plains. Russian olive was introduced from west Asia and Europe in the early 1900’s. It has now escaped cultivation in seventeen states and continues to spread.
Habitat: Both trees occur in disturbed areas, abandoned fields, pastures, and roadsides whore it they have been widely planted. They will quickly take over streambanks, lake shores, and wet meadows. These species also occur in open woodlands, prairies, and forest edges. They will rarely be found in dense forests. Russian olive does particularly well in sandy floodplains.
Uses: Autumn olive has been planted to revegetate disturbed areas (e.g., mining sites, roadsides). Russian olive has been widely used as an ornamental in the central and western US. Both of these species were also widely planted for wildlife habitat enhancement (birds as well as raccoons, foxes, skunks, opossums, and chipmunks are known to eat the fruits).
Life history: Plants flower and develop fruits annually after year three, although two-year old plants have been known to flower. One plant can produce 8 pounds of fruit Seed dispersal is done by falling fruit and fruit-consuming birds.
Threats to native species: Their prolific fruiting, seed dispersal, rapid growth and ability to thrive in poor soils makes it a heavy competitor with native species. Their nitrogen-fixing capabilities has the capacity to adversely affect natural communities whose native species are adapted to infertile soils.
Chemical control: A 10-20% solution of glyphosate (i.e., Roundup or Rodeo) applied to the cut stumps of these species is effective. This treatment is most successful during the growing season (July – September) but can also be effective during the dormant season. Glyphosate is a non-selective herbicide, so care should be taken to avoid contacting non-target plants when applying.
Spraying a band of undiluted triclopyr (i.e., Garlon 4) on the basal bark of the trees has yielded 95% kill. A narrow band of herbicide encircling the stem is needed to be effective. Application can be accomplished with a handheld sprayer and should be done during the dormant season prior to sap flow in the spring.
Foliar application of glyphosate, dicamba (i.e., Banvel) and 2,4-D (i.e., Crossbow and others) can provide total kill. A 1-2% solution of glyphosate is used for foliar applications. Banvel is mixed at 1 ounce per gallon of water with 0.5 ounces surfactant. 2,4-D is mixed according to the instructions. Complete coverage is necessary and therefore is best suited for shorter plants. Best time for application is during the later part of the growing season when plants are actively translocating materials to the roots. These herbicides are non-selective so care should be taken to avoid contact with other non-target species.
By state law, restricted-use herbicides must be applied according to label directions and by licensed herbicide applicators. Contact the Pesticide Bureau for details and to find out how to obtain a license.
Mechanical control: Young seedlings and sprouts can be pulled when adequate moisture is present (usually in the spring) to allow removal of the entire root system. These trees can be readily seen in the spring since they leaf out earlier than most native vegetation. Cutting alone should not be used since vigorous resprouting will occur.
Whatever control method is used, it will take a number of years to totally eradicate these invasive exotics from the infested area.
Dieter, L. 1996. Russian olive: Elaeagmts angustifdlia. Page 53 in John Randall and Janet Marinelli (eds.). Invasive plants: weeds of the global garden. Brooklyn Botanic Garden, Inc. 111pp.
Dittbemer, P.L., DJL Dietz, and C.H. Wasser. 1992. Autumn olive (glaeagnus umbellatd). US Army Corps of Engineers Wildlife Resources Management Manual, Dept of the Army 25pp.
Eckardt, N. 1987. Element stewardship abstract-JLlaeagnus lonbellata. The Nature Conservancy 6pp.
Smith, T. 1993. Missouri Vegetation Management Manual. Natural History Division, Missouri Dept of Conservation 148pp.
Sternburg, G. 1996. Autumn olive: Elaeagnus tanbellata. Page 54 in John Randall and Janet Marinelli (eds.). Invasive plants: weeds of the global garden. Brooklyn Botanic Garden, Inc. 111pp.
Szafoni, R.E. 1991. Vegetation management guideline: autumn olive. Natural Areas Journal 11 (2): 121 -122.
Virginia Dept. of Conservation & Recreation and the Virginia Native Plant Society. 1996. Invasive alien plant species of Virginia: Autumn olive and Russian olive. 2pp.
This fact sheet has been prepared by The Biodiversity Initiative of the Massachusetts Division of Fisheries & Wildlife.