Erica
Bell heather ( Erica tetralix ), illustration
The heathers (Erica ), also called pagans or Erika, are a genus of flowering plants in the family Ericaceae ( Ericaceae ), which comprises around 860 species. The majority are native to South Africa, only a few representatives radiate to Europe and the Middle East.
Colloquially, many dwarf shrubs of the heath " heather " are mentioned, without that they belong in the strict sense of the heathers (Erica ). This also applies to the closely related heather ( Calluna vulgaris), which often is the formative plant consisted of a heathland in Europe.
Description
Heathers are evergreen, prostrate shrubs and trees, which can be up to 10, rarely even to 30 feet tall. The Mark is uniform, the bud scales may be missing. Supporting and bracteoles are rare with the axillary shoot grown ( recauleszent ). The leaves are arranged in whorls, rarely opposite or scattered.
The petals wilt, however, are continuous, the small and carry leaf-like to large and colored, usually eight, rarely four or six or ten stamens usually have four, rarely are one to five sepals just to s -shaped stamens, and in cross-section flattened to cylindrical spurs on either at the extreme end of the stamens or the back on the anthers. Rarely, the pollen form monads.
The easy- to rarely strongly thickened, cup-shaped or bent-back style is significantly longer than the ovary, rarely it is missing almost completely or fell. Stigma lobes can be designed to be completely absent good
They usually have four, rarely one to eight carpels with usually more than one ovule. The fruits are drupes and open longitudinally along the outer walls ( loculicidal ) or not at all.
The chromosome number is n = 12, n = 18 rare
Dissemination
About 90 % of the species of the genus are native to southern Africa, the other species are found in the rest of Africa, Madagascar, the southwestern Arabian Peninsula, the Middle East or Europe. They are found from sea level to the Afro- alpine zone.
System
The first described by Linnaeus in 1753 already genus includes about 860 species. Together with the monotypic genera Daboecia and Calluna it forms the tribe Ericeae in the subfamily Ericoideae, this classification was supported by molecular genetic studies. The internal classification of the genus, however, is poorly understood and is considered open.
Some types of selection:
- Spring Heath (Erica carnea L., Syn: E. herbacea L.)
- Gray heather ( Erica cinerea L.)
- Bell heather ( Erica tetralix L.)
- Cornish heath (Erica vagans L.)
- Tree heath (Erica arborea L.)
- Erica abietina
- Erica australis
- Erica azorica
- Erica baccans
- Erica baueri
- Erica canaliculata
- Erica casta
- Scarlet heather ( Erica cerinthoides L.)
- Dorset Heath (Erica ciliaris L.)
- Erica cruenta
- Erica curviflora
- Erica diosmifolia
- Erica doliiformis
- Erica equisetifolia
- Purple heather ( Erica Erigena R. Ross)
- Erica fervida
- Erica glandulosa
- Erica glauca
- Erica gracilis
- Erica hebecalyx
- Erica hirta
- Erica holosericea
- Erica laeta
- Portuguese Heath (Erica lusitanica Rudolph)
- Erica mackayana
- Erica mammosa
- Erica manipuliflora
- Vielblütige heath (Erica multiflora L.)
- Erica nana
- Erica pageana
- Erica pater sonia
- Erica perspicua
- Erica Peziza
- Erica pillansii
- Erica pinea
- Erica quadrangularis
- Erica regia
- Erica scoparia
- Erica sitiens
- Erica spiculifolia
- Erica taxifolia
- Erica terminalis
- Erica totta
- Erica umbellata
- Erica versicolor
- Erica verticillata
- Erica vestita
- Erica viridescens
Evidence
- P.F. Stevens et al. Ericaceae. In: Klaus Kubitzki (ed.): The Families and Genera of Vascular Plants - Volume VI - Flowering Plants - Dicotyledons - Celastrales, Oxalidales, Rosales, Cornales, Ericales. 2004, pp. 173, ISBN 978-3-540-06512-8