Rhamnus lycioides, black hawthorn, european buckthorn, mediterranean buckthorn, is a species of flowering plant shrub in the buckthorn family, in the Buckthorns or Rhamnus genus, present in southern Europe and northern Africa.

Description

It is a slow growth shrub adapted to dry Mediterranean climate tangled, thorny and very branched. It is deciduous or evergreen, very rich in forms shrub of 1.5-3 meters high with many branches that form a tangle. The shrub is many times reinforced with spine and mostly of about 1 meter of a height. The bark is grayish stems and these are topped with spikes. Older branches are gray. Leaves are light green and, 0.5 to 3.5 centimeters long and 0.3 to 1 inch wide. The tip is obtuse to apiculate. It has narrow leaves entire, flat, linear-spatulate to obtuse. The leaf is entire is linear to obovate, glabrous, narrow and elongated sometimes slightly broadened towards the apex. They are sometimes leathery and persistent. Lateral nerves have little or no markings on the underside.

The yellow flower s are inconspicuous, standing in groups and appear in the winter. The calyx shows four sharp corners. Flower is very small, solitary or in small bundles in the axils of the leaves, greenish-yellow with 4 triangular lobes. The petals are rudimentary or nonexistent. The yellow flower s are inconspicuous, standing in groups and appearing in the winter. The calyx shows four sharp corners. The fruits ovoid, 4-6 millimeters large, yellowish and are beginning to ripen black. The fruit is a globose berry, with little meat, which resembles a tiny green grape initially and black at maturity. The berry is having inside a single seed or more, depending on the subspecies. Fruit round, small, dark. It has the curious property of not bloom or bear fruit at once. So, several specimens of the same population bear fruit in different months extending the availability of the species as food for birds that disperse their seeds. The berry is purgative and in large quantities is toxic to humans, but not for birds such as the warblers Mediterranean and other species.

Ecology

In the Iberian Peninsula is distributed throughout the central, eastern and south and its natural habitat are the sclerophyllous forest, and woods of pines, oaks, holm oaks and quercus coccifera. Its scientific name, and sometimes even its common name refers to its resemblance to the botanical genus lycium.

The species is found in the Mediterranean region, particularly in Spain and the Balearic Islands. It lacks the Corsica, growing on the Apennine Peninsula and in former Yugoslavia. (Rhamnus lycioides) on rocky, nutrient-poor soils.

Appears in sclerophyllous forests, scrub, and even solitary in severely degraded drylands as a pioneer species be cause the species is resilient to overgrazing and trampling by livestock. It is very resistant to drought preferring calcareous soils. Areas conducive to reaching 3 m high, in climates them extremely dry and windy appears as bushes in the rocks. Survives in desert areas with annual rainfall of 200 mm. with strong and frequent winds, high temperatures and little cloud cover, ie a large number of sunny days per year. These factors conducive to drying, add the important thermal inversions that further harden the weather. Thrives in dry forests and bushes, with the Kermes, the holm oak, Aleppo pine and juniper, under oaks, shrub oaks and pine trees ... It is a very hardy plant, which occupies poor soils, gritty and highly eroded. Along with the gorse and thistles are the latest species to disappear in overgrazed areas, being of inestimable value to small birds for its fruit and as the protection and support for their nests. The species is very important for desert birds by their fruits with high water content. The fruit can cause death in mammals, but is consumed by ants and birds.

Classification

Carl von Linné have described the Rhamnus lycioides subspecies Oleoides as a separate species Rhamnus oleoides, but it was in 1932 attributed to Rhamnus lycioides.

The Dartford Warbler, from the warmer parts of western Europe, and northwestern Africa. It is breeding in extreme spininess, shoots of Mediterranean scrub.

They have identified four subspecies of the black thorn, on the Mediterranean coast east of the Iberian peninsula appears a subspecies of black thorn Rhamnus called lycioides borgiae (Borja). Rhamnus lycioides oleoides (Olive tree) is in the Atlantic and west of the peninsula, Rhamnus lycioides velutina (velvet), in the provinces of Murcia, Almería, Granada and Malaga and the most widespread Rhamnus lycioides lycioides.

Detail of branches

References