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Russian Olive
Elaeagnus augustifolia |
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Country of Origin: |
The plant was first introduced in the late 1800’s
by means for ornamental use. It is native to Europe and Western Asia
(invasive species info). |
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History: |
The plant was
recommended for wildlife plantings, soil stabilization, and
windbreaks in some areas. It is a hardy long lived shrub/tree. It
reproduces primarily by seed production, but can and may establish
from underground root stalks. The seedlings can germinate anytime of
the year. It was first only being cultivated but has since
escaped. |
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Intended Use: |
The plant was
first introduced in the late 1800’s by means for ornamental use. |
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Mode of Invasion: |
It is a Eurasian
plant that was being cultivated. Now it is escaped and spreading
throughout the United States. Russian olive is being used throughout
the western United States as a soil moisture conservation and
wildlife habitat improvement program. In areas where it is abundant
it is well used by wildlife for food, while other states and areas
are trying to combat the problematic plant. |
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Species Description: |
This plant is part of the Oleaster family; it is
a fast growing tree with moderate heights from 10-25ft. They have
woody thorns on the trunk and branches reaching sizes of 1-2 inches,
Leaves are simple alternate, with a lanceolate leave shape to
oblong, entire edges, and are 1 ½-3 inches in length. The upper
surface has the silvery color because of the hairs, the under
surface is densely covered in silvery white scales. The flowers are
yellow, fragrant, and there arrangement is clusters. Fruits are
olive shaped, produce in large quantities, silvery when they first
come out and then turn to tan or brown (Northern State Univ. and
Agdepartment.com). |
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Map of Occurrence: |
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Effects of Invasion: |
Russian olive is a plant that can invade
quickly and in riparian areas. The tree forms dense monotypic
stands; it can out-compete other species in the areas as well such
as the plains cottonwood thus wildlife habitats are greatly changed
(Agdepartment.com). It is impossible to completely eradicate this
plant. Russian olive can also affect nutrient cycling and system
hydrology by connecting lowland riparian forests with open upland
areas near by. It provides food for wildlife they will utilize it
but is creating competition for surrounding plants in the
area (Borell 1951 and Northern State Univ.).
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Control: |
The options we have to control this plant are
early detection and rapid response. You can use mechanical removal
and pull out the saplings and the soil is moist and the diameter of
the sapling is 3 ½ inches. Also for larger trees you can dig out the
roots and tree but it is labor intensive to do this because you have
to get all rots seeing how the tree can re-sprout quickly from being
cut. You also can use chemical control such as Tricolopyr ester,
glyphosate, and imazapyr are found to be effective in controlling
Russian olive. Cut-stump and treat has been to be effective as well.
Foliar spraying and injection of herbicide is being used as well.
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References: |
www.Agdepartmet.com
(March 23, 2008)
Borell, A. E. 1951. Russian Olive as a
Wildlife Food. The Journal of Wildlife Management, Vol. 15 No. 1,
pp. 109-110.
Christensen, M. Earl. 1963. Naturalization
of Russian Olive (Elaeagnus angustifolia). American Midlan
Naturalist, Vol. 70, No. 1, pp. 133-137.
Northern State University:
www.northern.edu/natsource/TREESA1/Russia1.htm (March 23, 2008).
Shafroth, B. Patrick, Auble, T. Gregor,
Scott, L. Michael. 1995. Germination amd Establishment of the Native
Plains Cottonwood (Populus deltoids Marshall subsp. monilifera)
and the Exotic Russian-olive (Elaeagnus angustifloia).Conservation
Biology, Vol.9, No.5, pp.1169-1175.
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Click on the left to
learn about other invasive species in Oklahoma.
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