Italian buckthorn

Description

Rhamnus alaternus is a species of flowering plant in the buckthorn family Rhamnaceae, known by the common names Italian buckthorn or Mediterranean buckthorn. It is a hardy medium-sized evergreen shrub with fragrant flowers. Rhamnus alaternus is an evergreen shrub 1–5 metres (3 ft 3 in – 16 ft 5 in) high. The stems have reddish bark and pubescent young branches, rounded and compact foliage with alternating leaves, 2–6 centimetres (0.79–2.36 in) long, sometimes nearly opposite, oval or lanceolate, leathery, shiny green, yellowish-green underneath. The small fragrant flowers are gathered in a short axillary yellow-green raceme. The flowering period extends from February to April. Fruits are obovoidal red-brownish drupes of about 3–4 millimetres (0.12–0.16 in), containing from 2 to 4 seeds. The drupes darken to black when ripe. This species is widespread in thermophilic evergreen bush and scrubland of the Mediterranean climate regions, from Gran Canaria, Morocco and Portugal in the west, to the Levant in the east, from sea level up to 1,300 m (4,300 ft) altitude. The specific Latin name alaternus, is from the Latin word for the plant. Its origin is obscure but is often suggested to be of Etruscan or pre-Indo-European Mediterranean origin. In Australia, where it was introduced as a garden shrub, it has become a serious invasive woody weed in many areas, especially coastal parts of SE Australia. Here it displaces native shrubs of similar size such as the sea box, Alyxia buxifolia (an endemic plant which had an important medicinal role for aboriginal people). It prevents subshrubs and herbaceous ground cover native plants from surviving due the heavy shade and competition for moisture and nutrients. It can form dense thickets with very low biodiversity. This species is cultivated as an ornamental garden shrub, valued for its glossy evergreen leaves and red berries. The variegated cultivar 'Argenteovariegata' has gained the Royal Horticultural Society's Award of Garden Merit. Rhamnus is a genus of about 110 accepted species of shrubs or small trees, commonly known as buckthorns, in the family Rhamnaceae. Its species range from 1 to 10 m (3 to 33 ft) tall (rarely to 15 m, 50 ft) and are native mainly in east Asia and North America, but found throughout the temperate and subtropical Northern Hemisphere, and also more locally in the subtropical Southern Hemisphere in parts of Africa and South America.