Elaeagnus angustifolia

Elaeagnus angustifolia, commonly called Russian olive, silver berry, oleaster, or wild olive, is a species of Elaeagnus, native to Asia and limited areas of eastern Europe. It is widely established in North America as an introduced species.

Description
Elaeagnus angustifolia is a thorny tree growing to 35 ft in height. Its stems, buds, and leaves have a dense covering of silvery to rusty scales. The leaves are alternate, lanceolate, 4 – long and 1 - 2.5 cm broad, with a smooth margin. The plants begin to flower and fruit from 3 years old. The highly aromatic flowers, produced in clusters of one to three, are 1 cm long with a four-lobed creamy yellow calyx; they appear in early summer and are followed by clusters of fruit, a small cherry-like drupe 1 - 1.7 cm long, orange-red covered in silvery scales. The fruits are about 1 cm wide and sweet, though with a dryish, mealy texture.

The species is established and reproduced primarily by seed, with some vegetative propagation also occurring. The branches have thorns that can be 2 - 7 cm long.

Taxonomy
The first scientific description of Elaeagnus angustifolia was by Carl Linnaeus under its present name in 1753. Its common name comes from its similarity in appearance to the olive (Olea europaea), in a different botanical family, the Oleaceae.

Range
The native range of oleaster trees is from Ukraine and Turkey in the west and then eastwards through southern Russia and Central Asia into China. In the eastern Mediterranean this includes the East Aegean Islands, Lebanon, Syria, Palestine, and Israel. Further east in Asia the native range stretches into Afghanistan, Iran, Kazakhstan, Kyrgyzstan, Pakistan, Tajikistan, Turkmenistan, and the nations of the Caucasus. In India they are found in the western Himalayas. There is a disjunct population in Myanmar and Assam in eastern India. They grow natively in Mongolia and in China they are found in the north-central, southeast, Inner Mongolia, Manchuria, Qinghai, and Xinjiang.

Ecology


The shrub can fix nitrogen in its roots, enabling it to grow on bare mineral substrates.

The caterpillars of the high altitude alpine moth Lachana alpherakii use it as a host plant. The fruit is readily eaten and the seeds disseminated by many species of birds.

Invasive behavior
The species was introduced into North America by the late 19th century, and was both planted and spread through the consumption of its fruits (which seldom ripen in England), by birds, which disperse the seeds. Russian olive is considered to be an invasive species in many places in the United States because it thrives on poor soil, has high seedling survival rates, matures in a few years, and out-competes the native vegetation. It often invades riparian habitats where the canopy of cottonwood trees has died. Its quick-spreading root system can make it pest-like.

Uses
It is widely grown across southern and central Europe as a drought and cold-resistant ornamental plant for its scented flowers, edible fruit, attractive yellow foliage and black bark. It was grown in England by John Parkinson no later than 1633.

In Iran, the dried powder of the fruit is used mixed with milk for rheumatoid arthritis and joint pains. There is evidence supporting beneficial effects of aqueous extract of Persian olive in reducing the symptoms of osteoarthritis with an efficacy comparable to that of acetaminophen and ibuprofen.

It is one of the seven items used in Haft-sin, a traditional table setting of Nowruz, the traditional Persian spring celebration. The dried fruit, known locally as senjed, is one of seven served in its own syrup in a fruit salad called haft mēwa eaten during Nowruz in Afghanistan.

Chemistry
E. angustifolia contains the alkaloids harmine, harmane, and harmol in the roots and shoot, as well as calligonine in the bark.