Everlasting flowers

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Everlasting flowers
Helichrysum basalticum

Helichrysum basalticum

Systematics
Euasterids II
Order : Astern-like (Asterales)
Family : Daisy family (Asteraceae)
Subfamily : Asteroideae
Tribe : Gnaphalieae
Genre : Everlasting flowers
Scientific name
Helichrysum
Mill.

The plant genus of helichrysum ( Helichrysum ) belongs to the family of the daisy family (Asteraceae). The approximately 600 species are mainly native to the Old World , especially southern Africa and Madagascar .

Some species retain the color of their flower heads as they dry and are well suited for dry bouquets . They are also known as immortelles. The varieties of some species are suitable as bedding and balcony plants.

description

Appearance and leaves

Helichrysum grow as a one-, two-year to perennial herbaceous plants , semi-shrubs or shrubs , reach the most stature heights of 20 to 80 centimeters. Many species have an aromatic smell. They often form tap roots . The mostly upright, sometimes prostrate to ascending stems are more or less woolly-tomentose and usually have stalked or sedentary glandular hairs.

The alternately arranged leaves are usually stalked and encompassing the stem and / or descending. The simple leaf blades are egg-shaped, spatulate to lanceolate or linear with a wedge-shaped to truncated blade base. The entire edge of the leaf is sometimes rolled back. The two sides of the leaf are colored the same or less often differently and usually gray to white tomentose or silky hairs and they sometimes also have stalked or sessile glandular hairs; the upper side of the leaf sometimes becomes bald and is then greenish.

Inflorescences and flowers

In umbrella -shaped total inflorescences , several cup-shaped inflorescences are grouped together in clusters . The flower heads are more or less disc-shaped. The cup shell (involucre) is bell-shaped with a diameter of only 4 to 8 mm. The bracts, which are usually three to five, rarely up to seven rows, are whitish, straw to pink, red or orange and opaque to translucent and usually shiny. The bottom of the cup is flat and bare, with no leaves of chaff .

The petals are yellowish. Marginal functionally male flowers are absent or are present individually or in pairs. There are 3 to 30, rarely more than 50 inner, hermaphrodite flowers.

fruit

The more or less columnar achenes usually have a smooth, sometimes papillary surface, which is rough due to raised, roof-tile- shaped superimposed tips of the epidermal cells, and sometimes four to six longitudinal grooves and they are usually bald or rarely hairy. The pappus , which often falls off early, consists of a row of 12 to 20 bristles that are free or slightly contiguous at their base, usually bearded to rarely almost feathery bristles. The achenes are spread out as a diaspore .

Chromosome numbers

The basic chromosome number is x = 7.

Synecology

Some species are forage plants: sand straw flower ( Helichrysum arenarium ) for Aethes williana , Eublemma minutata , Platyptilia tesseradactyla ; Garden Strawflower ( Helichrysum bracteatum ) by Vanessa kershawi ; Italian everlasting flower ( Helichrysum italicum ) for Gypsochares baptodactylus Zeller 1850.

distribution

Many species come from the Capensis . Another focus of biodiversity is Australia . There are also comparatively few species in the Mediterranean region , in New Zealand and in western and central Asia .

Sand straw flower ( Helichrysum arenarium )
Inflorescence of the stinking straw flower ( Helichrysum foetidum )
Helichrysum moeserianum in Habitat, De Hoop Nature Reserve, South Africa
Inflorescence of Helichrysum umbraculigerum

Systematics

The genus Helichrysum was established in 1754 with the spelling Elichrysum by Philip Miller in The Gardeners Dictionary ... Abridged ... 4th edition, volume 2. Type species is Helichrysum orientale (L.) Gaertn. Synonyms for Helichrysum Mill. Are: Leontonyx Cass. , Virginea (DC.) Nicoli , Virginia (DC.) Nicoli . The generic name Helichrysum is derived from the Greek words helios for sun and chrysos for gold; Among the Greeks, helichrysos was a name for a Greek plant species from the Asteraceae family.

The genus Helichrysum belongs to the tribe Gnaphalieae in the subfamily Asteroideae within the family Asteraceae . The scope of the genus Helichrysum is under discussion, since it has been found that the previous genus is not monophyletic , outsourced genera are, for example, Argentipallium Paul G.Wilson , Castroviejoa Galbany et al. , Coronidium Paul G.Wilson , Lawrencella Lindl. , Xerochrysum Tzvelev , Ozothamnus R.Br. and Chrysocephalum Walp. with an oceanic spread.

In the species-rich genus of everlasting flowers ( Helichrysum ) there are around 600 species. Here is a selection of species:

For example, the following is no longer included in this category:

swell

  • Guy L. Nesom: Helichrysum - online with the same text as the printed work. In: Flora of North America Editorial Committee (Ed.): Flora of North America North of Mexico . Volume 19: Magnoliophyta: Asteridae, part 6: Asteraceae, part 1 (Mutisieae – Anthemideae). Oxford University Press, New York / Oxford a. a. 2006, ISBN 0-19-530563-9 , pp. 524 (English). (Section description and systematics)

Individual evidence

  1. Helichrysum at Tropicos.org. Missouri Botanical Garden, St. Louis
  2. a b c d e f g h i j k l m n o p q r s t u v Helichrysum in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland.
  3. M. Galbany-Casals, N. García Jacas, A. Susanna de la Serna, L. Sáez, Carles Benedí: Phylogenetic relationships in the Mediterranean Helichrysum (Asteraceae, Gnaphalieae) based on nuclear rDNA ITS sequence data. In: Australian Systematic Botany. Volume 17, No. 3, 2004, pp. 241-253, doi: 10.1071 / SB03031 .
  4. a b c d Werner Greuter (2006+): Compositae (pro parte majore). - In: W. Greuter & E. von Raab-Straube (eds.): Compositae. Euro + Med Plantbase - the information resource for Euro-Mediterranean plant diversity. Datasheet Helichrysum In: Euro + Med Plantbase - the information resource for Euro-Mediterranean plant diversity.

Supplementary literature

  • Peter Schönfelder, Ingrid Schönfelder: What is in bloom in the Mediterranean? 750 species (=  Kosmos nature guide ). 4th edition. Franckh-Kosmos, Stuttgart 2005, ISBN 3-440-10211-4 .

Web links

Commons : Everlasting Flowers ( Helichrysum )  - Collection of images, videos and audio files