Duration and Habit: Perennial Shrub
Thorny olive is a dense evergreen shrub. It is usually multi-stemmed and short. Sharp shoots give it a thorny appearance. Shrubs can grow 3.3-26.3 ft. tall. They are usually very dense with long shoots extending from the top. The leaves are alternate, oval to elliptical, with irregular wavy margins and silvery surfaces, 2-4 in. in length and thick. The axillary clusters of small, sweet-smelling, white to brown flowers develop in the fall. Plants rarely fruit, but fruit are small, red and dotted with small brown scales. Thorny olive closely resembles two other exotic olives, autumn olive and Russian olive.
Native Lookalikes: Currently no information available here yet, or there are no native Texas species that could be confused with Thorny olive.
Ecological Threat: It is able to grow and thrive in a variety of conditions, and can tolerant shade, drought, and salt. Animals and birds disperse seed, therefore widening its area of distribution. Reproduction also occurs via stem sprouts. When in its climbing form, it can climb into trees, choking out native vegetation.
Biology & Spread: The seeds are dispersed by animals, giving this plant the potential for rapid spread. It is able to grow and thrive in a variety of conditions, and can tolerant shade, drought, and salt. Animals and birds disperse seed, therefore widening its area of distribution. Reproduction also occurs via stem sprouts. When in its climbing form, it can climb into trees, choking out native vegetation.
History: horny olive is native to eastern Asia and was first introduced into the United States in 1830 as an ornamental.
U.S. Habitat: Very drought tolerant and can grow in most soils
U.S. Nativity: Introduced to U.S.
Native Origin: China and Japan
U.S. Present: AL, DC, FL, GA, KY, LA, MA, MS, NC, SC, TN, VA
Distribution in Texas: Planted as an ornamental in most of the southern U.S.
List All Observations of Elaeagnus pungens reported by Citizen Scientists
Remove all silverthorn plantings to prevent the spread and dispersal of seed. Educate the public on the potential dangers of invasive plants to prevent future plantings.
Remove plants prior to seed production. Revegetate natural areas with native species.
Aggressive tillage and/or mowing is an option whenever possible. Repeat as needed to control regrowth.
Silverthorn has very few pests or diseases in landscapes. There are no known biological agents.
Foliar applications of imazapyr or glyphosate with a surfactant in water have been used to treat silverthorn. Triclopyr as a 20% solution in a petroleum base with a penetrant can be used for upper stem treatments, as well as to young bark as a basal spray. Large stems can be cut and stumps treated immediately with imazapyr (10% solution), triclopyr (50% solution) or glyphosate (20% solution) in water with a surfactant.
From the U.S. Forest Service
* Thoroughly wet all leaves with Arsenal AC* or Vanquish* as a 1-percent solution in water (4 ounces per 3-gallon mix) with a surfactant (April to October).
* For stems too tall for foliar sprays, apply Garlon 4 as a 20-percent solution in commercially available basal oil, diesel fuel, or kerosene (2.5 quarts per 3-gallon mix) with a penetrant (check with herbicide distributor) to young bark as a basal spray (January to February or May to October). Or, cut large stems and immediately treat the stumps with one of the following herbicides in water with a surfactant: Arsenal AC* as a 10-percent solution (1 quart per 3-gallon mix) or a glyphosate herbicide as a 20-percent solution (2.5 quarts per 3-gallon mix).
MacDonald, G., B. Sellers, K. Langeland, T. Duperron, and E. Ketterer. 2008. Invasive Species Management Plans for Florida. University of Florida, IFAS Extension, Circular 1529.
Miller, James H. 2003. Nonnative invasive plants of southern forests: a field guide for identification and control. Gen. Tech. Rep. SRS-62. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 93 p.
Bugwood Network (invasive.org)
Google Search: Elaeagnus pungens
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USDA Plants: Elaeagnus pungens
Invasive Plant Atlas of the United States: Elaeagnus pungens
Bugwood Network Images: Elaeagnus pungens