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Description and biology
H. rhamnoides is a deciduous and hardy shrub that can grow between 2 and 4 m high (between 7 and 13 ft). It has a rough, brown or black bark and a thick, grayish-green crown. The leaves are alternate, narrow and lanceolate, with silvery-green upper faces. It is dioecious, meaning that the male and female flowers grow on different shrubs. The sex of seedlings can only be determined at the first flowering, which mostly occurs after three years. The male inflorescence is built up of four to six apetalous flowers, while the female inflorescence normally consists of only one apetalous flower and contains one ovary and one ovule. Fertilization occurs solely via wind pollination, which is why male plants need to be planted near the female plants to allow for fertilization and fruit production.

The oval or lightly roundish fruits grow in compact grapes varying from pale yellow to dark orange. Individual fruits weigh between 270 and 480 mg and contain high amounts of vitamin C, vitamin E, carotenoids, flavonoids and health-beneficial fatty acids, as well as higher amounts of vitamin B12 than other fruits.

The plants have a very developed and extensive root system, and the roots live in symbiosis with nitrogen-fixing Frankia bacteria. The roots also transform insoluble organic and mineral matters from the soil into more soluble states. Vegetative reproduction of the plants occurs rapidly via root suckers.

Taxonomy
H. rhamnoides is situated in the family Elaeagnaceae, in the order Rosales.

H. rhamnoides is divided into eight subspecies: ssp. carpatica, caucasia, fluviatilis, mongolica, rhamnoides, sinensis, turkestanica and yunnanensis. These subspecies vary in size, shape, number of main lateral veins in the leaves and quantity and color of stellate hairs. They also have different areas of distribution and specific utilizations.

"Sea buckthorn" is a term used for all species of the genus Hippophae. The genus name Hippophae originates from the Greek words hippo = "horse" and phaos = "to shine" and is due to the ancient Greek use of sea buckthorn leaves as horse fodder to make their coats shine more. The species name rhamnoides means "resembling the Rhamnus", refering to the buckthorn plant.

Distribution
H. rhamnoides is native to the cold-temperate regions of Europe and Asia, between 27 and 69EN latitude and 7EW and 122EE longitude. These regions include the Baltic Coasts of Finland, Poland and Germany, the Gulf of Bothnia in Sweden, as well as coastal areas of the United Kingdom. In Asia, H. rhamnoides can be found in the northern regions of China, throughout most of the Himalayan region, including India, Nepal and Bhutan, as well as in the northern regions of Pakistan and Afghanistan. It is found in a variety of locations: on hills and hillsides, valleys, riverbeds, along coastal regions, on islands, in small isolated or continuous pure stands, but also in mixed stands with other shrub and tree species. H. rhamnoides has also recently been planted in countries such as Canada, USA, Bolivia, Chile, South-Korea and Japan.

The current total acreage of H. rhamnoides is about 3.0 million ha worldwide. This number includes both wild and cultivated plants. Of these, approximately 2.5 million ha are situated in China (1.0 million ha of wild plants and 1.5 million ha in plantations), 20 000 ha in Mongolia, 12 000 ha in India and 3 000 ha in Pakistan. This makes China the largest agricultural producer of H. rhamnoides. Approximately 10 000 acres of the plant are planted in China each year for berry production as well as eco-environmental improvement. As of 2003, approximately 100 km of field shelterbelts were planted in Canada each year, and over 250 000 mature fruit-producing plants were grown on the Candian prariries with an estimated annual fruit supply of 750 000 kg. Other countries that grow H. rhamnoides as an agricultural plant include for example Germany and France.

Interactions
H. rhamnoides is involved in a number of interactions with other organisms, among which a symbiotic relationship with nitrogen-fixing bacteria, but also less advantageous interactions with fungal pathogens, insect pests and weeds. These relationships are explained in more detail below. H. rhamnoides is also involved in interactions with various animals (birds, rodents, deer, livestock) that can lead to damage in plantations, however these interactions are not discussed here.

Symbionts
H. rhamnoides plants that are 1-2 years old develop root nodules containing actinobacteria of the genus Frankia, which are capable of fixing nitrogen. As a result of this relationship, the soils in stands of H. rhamnoides are enriched in nitrogen. For instance after planting H. rhamnoides in a sand dune ecological system, the total soil nitrogen was increased by 1.5 times three years after planting, and by 3-6 times 50 years after planting. The nitrogen-fixing activity of the symbiotic bacteria is not constant, but depends on external factors such as climate or additional nitrogen fertilization.

Diseases and insect pests
Both in Asia and in Europe, sea buckthorn losses occur notably due to environmental stress, wilt disease and insect pests. It is estimated that more than 60 000 ha of natural and planted sea buckthorn stands have died in China since the year 2000 due to these three factors, and approximately 5 000 ha perish each year.

Wilt disease
Wilt disease is a combination of fungal diseases that is sometimes also called "dried-shrink disease", "shrivelled disease" , "dry rot" or "dry atrophy". In China, it causes fruit yield losses of 30-40% and annual losses of mature plantations of 4 000 ha. Several pathogens have been described as causing the sickness in sea buckthorn:
 * the genus Fusarium (Fusarium wilt): F. acuminatum, F. camptoceras and F. oxysporum, as well as F. rhizoctonia and F. solani and F. sporotrichioides
 * the genus Stigmina
 * the genus Verticillium (Verticillium wilt): V. albo-atrum and V. dahliae
 * the species Plowrightia hippophaes
 * the species Phellinus hippophaeicola
 * the species Phomopsis spp..

Methods to control the disease include removing and burning infected branches, not replanting H. rhamnoides at the same site for 3-5 years, and avoiding to make cuttings from infected plants. Antagonistic fungi like Trichoderma sp. or Penicillium sp. can be used to combat wilt disease in plants infected by Plowrightia hippophaes. Studies with these fungi showed a rate of infection prevention higher than 70% and a re-infection rate below 10%. Additionally, four strains of Cladothrix actinomyces were found to be usable as antagonistic fungi in H. rhamnoides plants infected by Fusarium sporotrichioides. Cultivars of H. rhamnoides that were relatively resistant to wilt disease have also been identified.

Insect pests
Green aphids (Capitophorus hippophaes) are one of the most damaging insect pests that affect H. rhamnoides. They are usually found in the new growth on shoot tips where they stunt growth and cause yellowing of the leaves. This is then followed by shrinking of the leaves along their central vain, after which they drop prematurely. Another serious pest is the seabuckthorn fruit fly (Rhagoletis batava), whose larvae feed on the fruit flesh, rendering the fruits unsuitable for use. H. rhamnoides is also affected by the gall tick (Vasates spp.), which causes gall formation on the leaves and thereby leads to deformation of the leaf surface. Both the leaf roller (Archips rosana) and the gypsy moth (Lymantria dispar) chew on H. rhamnoides leaves. The leaf roller occurs from May to July, while the gypsy moth occurs later in the summer. Further insect pests include the commashaped scale (Chionaspis salicis), which sucks sap from the bark and can cause important damage by leading to the death of the plant, and the larvae of the sea buckthorn moth (Gelechia hippophaella), which penetrate into fresh buds and feed on them. Thrips, and occasionally earwigs have also been observed as affecting H. rhamnoides.

Insecticides such as gammaxene and dylox are used to control insect pests in the soil, and insecticide soap can be employed against green aphid infestations

Weed control
Weed control is important, especially during the early growth stages of H. rhamnoides, since it grows slower than weeds due to its less vigorous root system. Weeds should be removed before planting by preparing the land adequately, and they should subsequently be controlled during the first four to five years, until the shrubs are high enough to shade out the weeds. Weed control is done both mechanically and manually. Weeding should however not be too deep so as not to damage the root system of H. rhamnoides.

As of 2003, no herbicides were registered for use in orchards of H. rhamnoides.