Doum palms

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Doum palms
Doum palm (Hyphaene thebaica)

Doum palm ( Hyphaene thebaica )

Systematics
Commelinids
Order : Palm- like arecales
Family : Palm family (Arecaceae)
Subfamily : Coryphoideae
Tribe : Borasseae
Genre : Doum palms
Scientific name
Hyphaene
Garden.

The doum palms ( Hyphaene ) are a genus of palm trees native to the arid regions of Africa and Arabia . They are characterized by strong above-ground branching of the trunks, which is otherwise rare in palm trees.

features

The Doum palms are small to large, single- stemmed or group-shaped fan palms , the trunks of which are usually multiple dichotomously branched. They are dioecious, separate sexes ( diocesan ) and bloom several times.

The leaf stalks are heavily reinforced. The leaves are induplicate and costapalmat. They remain on the plant after they have died ( marzescence ) and only fall below their own weight at a late stage. Characteristic is the often silver color and the lack of an abaxial hastula . The inflorescences are rather slender and stand between the leaves (interfoliar). The fruits are brown drupes .

Hyphaene differs from the closely related genera by the following combination of features: The fruit is shaped differently, distally it is expanded, it is mostly asymmetrical, rarely egg-shaped or spherical. The seed has an irregular shape, is not furrowed and has a homogeneous endosperm . The endocarp is not winged and has a terminal pore.

The chromosome number is 2n = 36.

Distribution and locations

The representatives occur in the rather dry areas of Africa, in the south to Natal and on Madagascar . In the north, the distribution area extends along the coast of the Red Sea and on the Arab side as far as the Gulf of Eilat . There are also occurrences on the west coast of India. Occurrences in Sri Lanka are possibly of human origin.

The doum palms grow mainly in arid and semi-arid areas, but the locations always have near-surface groundwater, so they grow along seasonal watercourses, on coastal sand dunes and plains and in oases. Hyphaene compressa rises in East Africa up to 1400 m above sea level. Hyphaene guineensis occurs in Gabon at locations close to the coast with high levels of rainfall, making it an exception within the genus.

Since all species are used by humans, the current distribution of the species does not necessarily coincide with their natural ones: destructive use may have restricted the area, unintentional or deliberate displacement may have expanded the area.

Systematics

The genus Hyphaene Gaertn. is placed within the family Arecaceae in the subfamily Coryphoideae , Tribus Borasseae and Subtribus Hyphaeninae. The genus is monophyletic . Her sister group is Medemia .

Numerous species names have been published, but there are only relatively few species. In the World Checklist of Selected Plant Families of the Royal Botanic Gardens (Kew) , the following species are recognized:

  • Hyphaene compressa H. Wendl. : The homeland is southern Ethiopia, Somalia, Kenya, Tanzania and Mozambique.
  • Hyphaene coriacea Gaertn. : The range extends from Ethiopia to southern Africa, Juan de Nova and Madagascar.
  • Hyphaene dichotoma (J. White Dubl. Ex Nimmo) Furtado : The home is north-western India and Sri Lanka.
  • Hyphaene guineensis Schumach. & Thonn. : The range extends from tropical West Africa to Angola.
  • Hyphaene macrosperma H. Wendl. : The home is tropical West Africa.
  • Hyphaene petersiana Klotzsch ex Mart. : The distribution area extends from Tanzania to Namibia. Knownonly as Makalani in Namibia.
  • Hyphaene reptans Becc. : The homeland is Somalia, northern Kenya and Yemen.
  • Hyphaene thebaica (L.) Mart. : The range extends from tropical West Africa to Egypt and the Arabian Peninsula.

use

Seeds of the doum palm

All doum palms are of great local economic importance, especially in subsistence agriculture. The leaves are used for roofing and to produce fibers for braiding. The shoot cone is used to tap palm wine . The wood is used in many ways. The fruits provide an edible mesocarp , and the endocarp of unripe fruits is also edible.

The crushed fruits are brewed like tea and sweetened and drunk cold (doum drink).

What is more important, however, is the endosperm of ripe fruits, which is used as a vegetable ivory like that of the stone nuts . All parts of the palm trees, unless otherwise usable, serve as fuel.

Doum palm wood was used in traditional clay mosque architecture in Niger and Mali , such as the Great Mosque of Agadez and the clay mosques of Timbuktu .

literature

  • John Dransfield, Natalie W. Uhl, Conny B. Asmussen, William J. Baker, Madeline M. Harley, Carl E. Lewis: Genera Palmarum. The Evolution and Classification of Palms . Second edition, Royal Botanic Gardens, Kew 2008, ISBN 978-1-84246-182-2 , p. 314 ff.
  • Chris Scarre : The Seventy Wonders of the World, Mankind's Most Mysterious Structures and How They Were Erected. 3rd edition, 2006, Frederking & Thaler, ISBN 3-89405-524-3 .

Individual evidence

  1. Rafaël Govaerts (ed.): Hyphaene. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved April 15, 2020.
  2. Chris Scarre: The Seventy Wonders of the World, The Most Mysterious Buildings of Mankind and How They Were Built, pp. 143-145 (see LIT.)

Web links

Commons : Doumpalmen ( Hyphaene )  - Collection of images, videos and audio files
  • Hyphaene on the homepage of the Fairchild Tropical Botanic Garden