Dioecious phanerophyte. Deciduous shrub, often forming dense, extended stands, or rarely a small tree (up to 6 m); all green parts densely to moderately densely covered with peltate, fringed, silvery or copper-brown scales. Roots vertical, to 1 m depth (sometimes also horizontal roots, creeping extensively near the surface). Stems usually angled and curved, ascending or patent, to 15(-30) cm thick, richly and densely branched with many dead branches remaining below the leaf-bearing ones; living branches thorny from transformed side-shoots and apical shoots. Leaves alternate, densely set along this year’s long-shoot and on short-shoots along last year’s long-shoot; petioles 1-3(-5) mm; blade rather thick, lanceolate, 35-65 x 5-8 mm, grey-green above and silvery grey beneath, with subacute apex, attenuate base and entire margin.

Distribution. Nem–NBor(–LAlp). Alt. N Op 1140 m. D fairly common along the North Sea from VJy Blåvands Huk to NJy Skagen, and at Limfjorden from VJy Tyborøn to NJy Ålborg; ØJy rare, mainly at Århus Bugt; FyL Weddelsborg Hoved; LFM locally abundant in eastern Falster and eastern Møn; Sjæ rare, mainly in the northwest and in Stevns. N scattered on sandy shores and scree slopes from ST Melhus, Orkdal and Hitra to Tr Ibestad; rare on inland scree and in willow swamps in Op Lom, Skjåk and SF Stryn; often escaped from cultivation and spreading in sandy places along the coast from Øf to Ro and inland to Bu Nore and Uvdal. S common along most of the coast from central Upl to eastern Nb but almost lacking from northern Gst to central Hls and from northern Mpd to central Ång; in the coastal areas scattered occurrences inland, more or less ephemeral (relictual or bird spread). BhG rare in screes in the central and northern part. Öl a few coastal localities with one to a few individuals, possibly spontaneous there and in western Sk (Öresund). Elsewhere planted and escaped or persisting, most frequently in sandy coastal areas, in the rest of Sk, Gtl, Hl and BhG Göteborg. F common in A and along the Bothnian coast from the SW archipelago of V to KP, less frequent from OP to western PeP; elsewhere introduced and escaped on seashore (at least in U Espoo and Helsinki and EK Kotka) or recorded from dumps, filling earth or along railways (V Nummi-Pusula and Salo, EH Hämeenlinna, Kärkölä and Tampere, ES Kouvola and Lappeenranta and PeP Kemijärvi).

Habitat. Sun-exposed places with sand, gravel or stones, and without closing vegetation; calciphilous; very sensitive to competition and shade. Seashores, in particular when subject to land uplift with slight to moderate exposition to the sea; coastal sand-dunes; scree. Usually more or less ephemeral in man-made habitats: gravel- and sand-pits, road cuttings, railways, sandy ditches, edges of fields, dump heaps. From the 1990’s increasingly common in cultivation.

Biology. On land uplift shores the species may form scrub coherent along vast stretches of coast line, keeping pace with rise of new formed land. New shoots and roots grow outwards towards light and empty, surged soil, while the inner, old and high parts of the scrub successively die from competition and shade (Palmgren 1912) combined with fungal infestations, especially by Phellinus species (Jahn 1965). A Hippophaë stand must slowly shift its position to remain alive, as it is constantly depending on open soil.

History. Numerous finds of fossil pollen and macrofossils indicate that Hippophaë was among the earliest and most important late-glacial invaders into Norden. Fossil pollen has been found in Norden from D SJy and Brn in the south to F KiL in the north (e.g. Sandegren 1943, Hafsten 1966). The populations in Denmark, in Norway from ST north to Tr and in the Bothnian area are most probably relictual from the pioneer phase, while those in S northern BhG have been considered of more recent date (Palmér 1920) or even very recent (Magnusson 1918).

Variation and taxonomy. There is obvious variation in plant height within Norden; in D Jylland the shrubs are low and do not reach tree dimensions as may be the case at the Bothnian Sea in S and F. This variation was confirmed in cultivation experiments by Rousi (1971). Plants from scree and shore localities in N SNo have narrower leaves than the Baltic population.

Phanerophytes. Deciduous shrubs or small trees; young shoots and leaves more or less densely covered by silvery, peltate, fringed scales. Leaves alternate, petiolate, undivided; margin entire. Inflorescences axillary, compact clusters of one to rather few flowers. Flowers bisexual, epigynous, usually with a constriction above the tubular hypanthium and a nectariferous disk above the constriction; perianth campanulate, 4-lobed. Stamens 4, inserted inside the upper part of the perianth; filament very short. Ovary superior, with one style and an oblique stigma. Fruit a drupe with an ellipsoid, ribbed stone.

Shrub with suckers, extensively branched, up to 4 m. Shoots as young with a dense cover of deeply fringed brownish scales and some stellate hairs; old shoots with dark-brown, somewhat pruinose bark. Leaves rather densely arranged along the shoots; petiole 2–9 mm; blade grey above, silvery grey below, narrowly to broadly elliptic or ovate, acute to obtuse, rounded at base, (2.2–)3.5–8 x (0.8–)1.5–5 cm; both surfaces densely covered with silvery scales (on lower surface also single to scattered brownish ones, in particular along the midvein).

Distribution and habitat. From the beginning of the 20^th century increasingly grown in parks and gardens north to northern Norway and Sweden and central Finland. Sometimes persistent after cultivation or escaped, spreading by means of extensive suckers. Open, rather dry, gravelly to sandy places; roadsides, ditches, railways, waste places, gravel pits, abandoned sites. D scattered in most parts. S scattered or rare north to Vsm and Upl. N a few places in the south (Øf Rakkested, Ak Ås, Bu Drammen, VA Farsund) and in the north NNo Hamarøy. F reported as escaped from dozens of places north to southern PK, but usually a mere relic of cultivation; no confirmed established occurrences.