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RUSSIAN - OLIVE - Elaeagnaceae (Oleaster family)

Russian olive trees are common in Fremont County.  Silvery to grey-green, hardy, and fast growing, they were once planted as wind rows and make good shade trees.  In yards, the silver color creates a good contrast with other trees leading to the ornamental use of the tree.  In the wild the contrast ends because it crowds out other varieties.  While people and animals avoid contact with the trees because of the long tearing thorns, many birds find protection and food in their branches.  Because birds often transport the seeds to undesirable locations, they have become “weedy” in low lying areas and along water ways, preventing livestock, wildlife, and humans access to the water.

Leaves are narrow and long, some of the last to emerge in the spring and last to drop in the fall.  They are covered with tiny scales which creates the silvery appearance.

The small four petaled flowers grow in clusters towards the outer ends of the limbs and have a very strong sweet smell.  The flowers mature into small silvery olive shaped fruits that may turn red, brown or tan. 

The seedling is light colored, covered by fuzz and scales, with small oval leaves, almost straight up with a tenacious root.  Soon the bark becomes smooth and turns brown or reddish developing long hard tearing thorns.  The mature tree has rough brown bark that may hang off in papery layers.

The following is courtesy of Weeds of the West:
A fast-growing tree of moderate size, normally reaching heights from 10 to 25 feet. Trunks and branches are armed with 1-2-inch woody thorns. Leaves are narrow, 2 to 3 inches long, and covered with minute scales which give the foliage a distinctive silvery appearance. Scales are usually more abundant on the underside of leaves. Flowers are yellow, and arranged in clusters. Fruits, shaped like small olives, are silvery when first formed, but turn tan to brown at maturity.

Introduced from Europe, Russian-olive is promoted as a desirable ornamental shade tree, and is recognized as a source of food and protection for wildlife. However, when allowed to invade low-lying pastures, meadows, or waterways it can become a serious weed problem.
(Courtesy of Weeds of the West)