Texas Invasive Species InstituteElaeagnus umbellata
Autumn Olive
Class: Magnoliopsida
Order: Rhamnales
Family: Elaeagnaceae
Photographer: Mark A. Garland @ USDA-NRCS PLANTS Database
Source: http://plants.usda.gov/
Description
Elaeagnus umbellata is a many-branched, deciduous shrubby tree that can grow from 10 to 16 feet. Leaves are alternate, simple and vary in size. Thorns are present, formed on spur branches, and several inches in length. The fruits are single-seeded and 0.2-0.4 inches in diameter. Numerous fruits are produced. They are small, red-brown to pink and dotted with brown or silvery scales.
Ecological Threat: Autumn Olive is a particularly invasive species and is listed as a category 1 weed by the U.S. Forest Service for the Southern Region. This means it is known to persist in native plant communities and displace native plant species and can threaten natural ecosystems and alter habitats. The introduction of Category 1 is prohibited on National Forest System Lands because it is able to persist and overtake native communities. Also, since it is able to fix nitrogen it takes the compound away from native nitrogen-fixing plants. Studies have shown the fruits to have health benefits because it has high level of Lycopene and some encourage its presence. However, even though it provides benefits the commercial growth/distribution and in turn the spread to native lands severely compromises native ecosystems.
Biology: Autumn olive propagates primarily by seeds but can sprout vegetatively, so mowing or cutting can cause a quick expansion of the plant population. Also, birds and mammals help disperse the seeds far and wide, and the seeds can remain viable up to 3 years. Seedlings take 3 to 5 years to become fully mature trees and each tree can produce up to 8 pounds of fruit. Flowers occur in the late spring and fruits are matured from August to October.
History: Imported from China, Korea and Japan in the 19th century, to attract wildlife and control erosion. Nowadays, research has shown that native species provide more benefits without the alterations in nutrient cycling, hydrology or decrease in native biodiversity.
U.S. Habitat: Disturbed areas, along roadsides or pastures and fields. Found in poor soils because it has root nodules that are nitrogen fixing that allow it to tolerate such soil conditions. It is also drought tolerant but can survive in riparian areas.
Distribution
Native Origin: Was introduced in 1830 as an ornamental and to be used for wildlife habitat and erosion control.
U.S. Present: AL, AR, CT, DC, DE, FL, GA, HI, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MO, MS, MT, NC, NE, NH, NJ, NY, OH, OR, PA, RI, SC, TN, VA, VT, WA, WI and WV.
Resembles/Alternatives
Elaeagnus umbellata tree resembles its fellow congener Russian olive (Elaeagnus angustifolia) which is also an invasive plant but can grow in riparian zones and prefers shaded areas. Also, the leaves are narrow-elongate with silvery scales and the fruit is yellow to silvery as opposed to reddish.
Management
Hand pulling small seedlings can be effective. However, mowing or cutting can cause hearty re-sprouting, even repeated cutting is ineffective. After cutting, Triclopyr and glyphosate are effective on re-sprouts during the growing season. Glyphosate can also be effective when directly applied to freshly cut stumps. Multiple treatments may be required.
Text References
Internet Sources
http://www.invasivespeciesinfo.gov/plants/autmnolive.shtml
http://www.fs.fed.us/database/feis/plants/shrub/elaumb/all.html#14
http://www.nps.gov/plants/alien/pubs/midatlantic/elum.htm
http://www.psa-rising.com/eatingwell/wild-foods/autumnolive.htm
