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Dracaena draco

Dracaena draco
The ancient specimen El Drago Milenario at Icod de los Vinos, Tenerife (Canary Islands, Spain)
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Asparagaceae
Subfamily: Nolinoideae
Genus: Dracaena
Species:
D. draco
Binomial name
Dracaena draco
(L.) L.[2]
Synonyms[3]
  • Palma draco (L.) Mill.
  • Asparagus draco L.
  • Dracaena resinifera Salisb.
  • Draco arbor Garsault
  • Draco draco (L.) Linding.
  • Draco dragonalis Crantz
  • Drakaina draco (L.) Raf.
  • Stoerkia draco (L.) Crantz
  • Yucca draco (L.) Carrière

Dracaena draco, the Canary Islands dragon tree or drago,[4] is a subtropical tree in the genus Dracaena, native to the Canary Islands, Cape Verde, Madeira, western Morocco, and possibly introduced into the Azores.[5]

It was first described by Carl Linnaeus in 1762 as Asparagus draco.[3][6] In 1767 he assigned it to the new genus, Dracaena.[3][7]

A related tree of similar appearance, the Socotra dragon tree Dracaena cinnabari, grows on the island of Socotra, Yemen, more than 7000 km from the Canary Islands.

Description

Dracaena draco subsp. ajgal in the village Agadir Ougjgal near Tiznit, Morocco

Dracaena draco is an evergreen long lived tree capable of exceeding 15 m (49 ft) in height and having a trunk of 5 m (16 ft) or more in circumference, starting with a smooth bark that evolves to a more rough texture as it ages.[8] The "dragon tree" is a Monocot, with a branching growth pattern currently placed in the asparagus family (Asparagaceae, subfamily Nolinoidae).[9] When young it has a single stem. At about 10–15 years of age the stem stops growing and produces a flower spike with white, lily-like perfumed flowers, followed by coral berries. Soon a crown of terminal buds appears and the plant starts branching. Each branch grows for about 10–15 years and re-branches, so that a mature plant has an umbrella-like habit. It grows slowly, requiring about 10 years to reach 1.2 metres (4 ft) in height, but at times, grows much faster.[clarification needed][10]

Despite being a monocotyledon, it has annual growth rings. There is considerable genetic variation within the Canary Island dragon trees. The form found on Gran Canaria is now treated as a separate species, Dracaena tamaranae, based on differences in flower structure. The form endemic to La Palma, initially branches very low with numerous, nearly vertical branches arranged fastigiately. There is a forest of such trees at Las Tricias, Garafia district, La Palma.[11][12]

Subspecies:

  • D. draco subsp. draco: Endemic to Madeira and Canary Islands[13]
  • D. draco subsp. ajgal Benabid & Cuzin: Endemic to Morocco[14]
  • D. draco subsp. caboverdeana Marrero Rodr. & R.S.Almeida: Endemic to the Cape Verde islands[15]

Distribution and habitat

Inflorescence

Dracaena draco is native to Macaronesia and southwest Morocco, where it is commonly cultivated as an ornamental plant. On the Canary and Madeira archipelagos, wild endemic populations today are known only in Tenerife and Madeira after recently going extinct in the wild in Gran Canaria. Wild populations in Morocco extend to the southwest Atlas Mountains. Its origin on the Azores is uncertain but it is thought to result from an introduction made by the Portuguese prior to 1500 with seeds from Madeira and Cape Verde, as some individuals were observed to have similarities with the Cape Verdean subspecies (subsp. caboverdeana); there are around 200-300 individuals on remote sites in the island of São Jorge and a few more on other islands and it is unknown if these populations can be considered native or the result of an early introduction.[5][16]

Uses

Fruits

When the bark or leaves are cut they secrete a reddish resin, one of several sources of substances known as dragon's blood. Red resins from this tree contain many mono- and dimeric flavans that contribute to the red color of the resins.[17] Dragon's blood has a number of traditional medical uses, although dragon's blood obtained from Dracaena draco was not known until the 15th century,[18] and analyses suggest that most dragon's blood used in art was obtained from species of the genus Calamus formerly placed in Daemonorops.[19] The primary and secondary plant body are the site of the secretory plant tissues that form dragon's blood. These tissues include ground parenchyma cells and cortex cells.[20] Dragon's blood from Dracaena draco and Dracaena cinnabari can be distinguished by differences in 10 compounds and a dominant flavonoid DrC11 missing in Dracaena draco.[19]

The Guanches worshiped a specimen in Tenerife, and hollowed its trunk into a small sanctuary. Alexander von Humboldt saw it at the time of his visit. It was 70 feet (21 m) tall and 45 feet (14 m) in circumference, and was estimated to be 6,000 years old. It was destroyed by a storm in 1868.[21]

Cultivation

Dracaena draco is cultivated and widely available as an ornamental tree for parks, gardens, and drought tolerant water conserving sustainable landscape projects. It has gained the Royal Horticultural Society's Award of Garden Merit.[22][23]

In 2017, the city of Angra do Heroísmo (Terceira Island) planted a grove of 200 dragon trees.[24][25]

The Museum of Wine on Pico Island, Azores, has one of the largest concentrations of this species in Macaronesia, some being more than 100 years old.[26]

Symbolism

Dracaena draco is the natural symbol of the island of Tenerife, together with the blue chaffinch.[27]

Notable trees

Photo Name Location
El Drago Milenario Icod de los Vinos, Tenerife
Dragos Gemelos Breña Alta, La Palma

See also

Citations

  1. ^ Silva, L.; Caujapé-Castells, J.; Lobo, C.; Casimiro, P.; Moura, M.; Elias, R.B.; Fernandes, F.; Fontinha, S.S.; Romeiras, M.M. (2021). "Dracaena draco". IUCN Red List of Threatened Species. 2021: e.T30394A119836316. doi:10.2305/IUCN.UK.2021-2.RLTS.T30394A119836316.en. Retrieved 19 November 2021.
  2. ^ "Dracaena draco", World Checklist of Selected Plant Families, Royal Botanic Gardens, Kew, retrieved 2013-11-12
  3. ^ a b c "Dracaena draco (L.) L. | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2021-09-17.
  4. ^ "Forest 15 - Dragon Tree", National Arboretum Canberra, Australian Government, archived from the original on 2018-09-23, retrieved 2018-09-22
  5. ^ a b Almeida Pérez, R.S. & Beech, E. (2017). "Dracaena draco". IUCN Red List of Threatened Species. 2017: e.T30394A103368016.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  6. ^ Linnaeus, C. (1762). Species plantarum. Vol. 1 (2 ed.). p. 451.
  7. ^ Linnaeus, C. (1767). "Dracaena". Systema Naturae: Per Regna Tria Natura, Secundum Classes, Ordines, Genera, Species, Cum Characteribus, Differentiis, Synonymis, Locis (Ed. 12). 2: 246.
  8. ^ "Dracaena draco (L.) L." University of Madeira. Retrieved 13 January 2021.
  9. ^ Chase, M.W.; Reveal, J.L. & Fay, M.F. (2009). "A subfamilial classification for the expanded asparagalean families Amaryllidaceae, Asparagaceae, and Xanthorrhoeaceae". Botanical Journal of the Linnean Society. 161 (2): 132–136. doi:10.1111/j.1095-8339.2009.00999.x.
  10. ^ "Dracaena Draco Farm". Retrieved 2011-11-03.
  11. ^ "Dracaena draco". www.floradecanarias.com.
  12. ^ "Buracas". visitlapalma.es. Visit La Palma.
  13. ^ "Dracaena draco subsp. draco". Catalogue of Life. Retrieved 13 January 2021.
  14. ^ "Dracaena draco subsp. ajgal Benabid & Cuzin". Catalogue of Life. Retrieved 13 January 2021.
  15. ^ Rodríguez, Pérez. "A new subspecies, Dracaena draco (L.) L. subsp. caboverdeana Marrero Rodr. & R.S. Almeida (Dracaenaceae) from the Cape Verde Islands". Retrieved 13 January 2021 – via researchgate.net.
  16. ^ "Dracaena draco subsp. draco". Flora-on. Retrieved 13 January 2021.
  17. ^ Porter, Lawrence J. (1988-01-01). "Flavans and proanthocyanidins". In Harborne, J. B. (ed.). The Flavonoids. Springer US. pp. 21–62. doi:10.1007/978-1-4899-2913-6_2. ISBN 9780412287701.
  18. ^ Gupta, D.; Bleakley, B.; Gupta, R.K. (2007). "Dragon's blood: Botany, chemistry and therapeutic uses". Journal of Ethnopharmacology. 115 (3): 361–380. doi:10.1016/j.jep.2007.10.018. PMID 18060708. Retrieved 2015-02-17.
  19. ^ a b Baumer, Ursula; Dietemann, Patrick (2010-06-01). "Identification and differentiation of dragon's blood in works of art using gas chromatography/mass spectrometry". Analytical and Bioanalytical Chemistry. 397 (3): 1363–1376. doi:10.1007/s00216-010-3620-0. ISSN 1618-2642. PMID 20349349. S2CID 13267387.
  20. ^ Jura-Morawiec, Joanna; Tulik, Mirela (2015-05-01). "Morpho-anatomical basis of dragon's blood secretion in Dracaena draco stem". Flora - Morphology, Distribution, Functional Ecology of Plants. 213: 1–5. Bibcode:2015FMDFE.213....1J. doi:10.1016/j.flora.2015.03.003.
  21. ^ Gilman, D. C.; Peck, H. T.; Colby, F. M., eds. (1905). "Dracæna draco" . New International Encyclopedia (1st ed.). New York: Dodd, Mead.
  22. ^ "RHS Plant Selector - Dracaena draco". Retrieved 1 June 2020.
  23. ^ "AGM Plants - Ornamental" (PDF). Royal Horticultural Society. July 2017. p. 33. Retrieved 6 February 2018.
  24. ^ "DiarioInsular.pt". www.diarioinsular.pt.
  25. ^ "Bosque de Dragoeiros · Tv. do Fanal, Angra do Heroísmo, Portugal". Bosque de Dragoeiros · Tv. do Fanal, Angra do Heroísmo, Portugal.
  26. ^ "Mata de Dragoeiros". Pico Museums. Retrieved 13 January 2021.
  27. ^ Símbolos de la naturaleza para las Islas Canarias [Natural Symbols for the Canary Islands] (Ley 7/1991) (in Spanish). Vol. 151. 30 April 1991. pp. 20946–20497 – via BOE.

General bibliography

Quelle: http://en.wikipedia.org/wiki/Dracaena_draco