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''Dracaena cinnabari'', the Socotra dragon tree or dragon blood tree, is a dragon tree native to the Socotra archipelago in the Indian Ocean. It is so called due to the red sap that the trees produce. ==Description== The dragon blood tree is the most famous and beautiful and distinctive plant of the island of Socotra. It has a unique and strange appearance, described as "upturned, densely packed crown having the shape of an uprightly held umbrella". This evergreen species is named after its dark red resin, which is known as "dragon's blood". Unlike most monocot plants, the Dracaenaceae display secondary growth, ''D. cinnabari'' even has growth zones resembling tree rings found in dicot tree species. Along with other arborescent ''Dracaena'' species it has a distinctive growth habit called "dracoid habitus". Its leaves are found only at the end of its youngest branches; its leaves are all shed every 3 or 4 years before new leaves simultaneously mature. Branching tends to occur when the growth of the terminal bud is stopped, due to either flowering or traumatic events (e.g. herbivory).〔 Its fruits are small fleshy berries containing between 1 and 3 seeds. As they develop they turn from green to black and then become orange once they are ripe. The berries are eaten by birds (e.g. ''Onychognatus'' species) and thereby dispersed. The seeds are 4–5 mm in diameter and weigh on average 68 mg.〔 The berries exude a deep red resin, known as dragon’s blood. Like other monocotyledons, such as palms, the dragon’s blood tree grows from the tip of the stem, with the long, stiff leaves borne in dense rosettes at the end (4, 5, 7). It branches at maturity to produce an umbrella-shaped crown, with leaves that measure up to 60 cm long and 3 cm wide. The trunk and the branches of the dragon blood are thick and stout and display dichotomous branching, where each of the branches repeatedly divides in two sections. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dracaena cinnabari」の詳細全文を読む スポンサード リンク
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