Today's entry is again written by Bryant:
A big thank you to Anne Elliott (aka annkelliott@Flickr) for today's image of Hippophae rhamnoides (commonly referred to as sea-buckthorn). It is a medium sized (2-4 meters tall) deciduous shrub that often grows in dense thickets on fixed dune habitats in both Europe and Asia. These thickets develop as the rhizomes spread out and shoot up suckers (or basal shoots). As its common name would suggest, its branches are laden with thorns, each about a few centimeters (1-2 inches) long. Also of note is that it is not a true buckthorn (Rhamnaceae) but rather a member of the Elaeagnaceae; its specific epithet rhamnoides means "resembling buckthorn". During the spring and summer, Hippophae rhamnoides has narrow, lanceolate leaves with a silvery-green upper surface.
Hippophae rhamnoides is dioecious and fruits develop on female plants during the late summer, often persisting on the plant until the following spring. The profusion of the nutrient-rich fruits and their persistence make this species an important winter food source for wildlife and people. Fruits harvested toward the end of winter still showed higher levels of vitamin C (by weight) than found in ripe oranges. Hippophae rhamnoides has an extensive ethnobotanical history, perhaps dating as far back as the Mesolithic. There is an excellent review of the palaeoethnobotanical/nutritional aspects of this species in the BBC series Ray Mears Wild Food. The series may be purchased via Ray's site, but there also appears to be some episodes uploaded to Youtube.
Hippophae rhamnoides is cultivated widely for the oils found in the seeds. This oil is used as an ingredient in many naturopathic remedies and cosmetics; its use is most popular in Europe and Asia. Hippophae rhamnoides is also cultivated for its ability to stabilize slopes and for its relationship with nitrogen-fixing actinomycetes.