Dracaena cinnabari Balf.f.

Asparagaceae

Dracaena (plant) - Wikipedia

국표에서는 앵글러 과명  Liliaceae (백합과)이다.

국표에 없다.

Dracaena cinnabari, the Socotra dragon tree or dragon blood tree, is a dragon tree native to the Socotra archipelago, part of Yemen, located in the Arabian Sea. It is named after the blood-like color of the red sap that the trees produce.

 

Description

Young specimen of Dracaena cinnabari in the Koko Crater Botanical Garden, Honolulu, Hawaii, United States

Dragon trees at the edge of the gorge in Socotra

The dragon blood tree has a unique and strange appearance, with an "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, Dracaena displays 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 4 seeds. As they develop they turn from green to black, and then become orange when ripe. The berries are eaten by birds (e.g. Onychognatus species) and thereby dispersed. The seeds are 4–5 mm (0.16–0.20 in) 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 (24 in) long and 3 cm (1.2 in) 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 into two sections.

Biology

The dragon's blood tree usually produces its flowers around March, though flowering does vary with location. The flowers tend to grow at the end of the branches. The plants have inflorescences and bear small clusters of fragrant, white, or green flowers. The fruits take five months to completely mature. The fruits are described as a fleshy berry, which changes from green to black as it gradually ripens. The fleshy berry fruit ends up being an orange-red color that contains one to three seeds. The berries are usually eaten and dispersed by birds and other animals.

The different shape of the dragon's blood tree is an adaptation for survival in arid conditions with low amounts of soil, such as in mountaintops. The large, packed crown provides shade and reduces evaporation. This shade also aids in the survival of seedlings growing beneath the adult tree, explaining why the trees tend to grow closer together.

Taxonomy

The first description of D. cinnabari was made during a survey of Socotra led by Lieutenant Wellsted of the East India Company in 1835. It was first named Pterocarpus draco, but in 1880, the Scottish botanist Isaac Bayley Balfour made a formal description of the species and renamed it as Dracaena cinnabari. Of between 60 and 100 Dracaena species, D. cinnabari is one of only six species that grow as a tree.

Evolution

Along with other plants on Socotra, D. cinnabari is thought to have derived from the Tethyan flora. It is considered a remnant of the Mio-Pliocene Laurasian subtropical forests that are now almost extinct due to the extensive desertification of North Africa.

dragon blood tree - Bing images

https://youtu.be/53Dvkuic5YU?t=1022