River Ragwort

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River Ragwort
River ragwort (Senecio sarracenicus)

River ragwort ( Senecio sarracenicus )

Systematics
Order : Astern-like (Asterales)
Family : Daisy family (Asteraceae)
Subfamily : Asteroideae
Tribe : Senecioneae
Genre : Field herbs ( Senecio )
Type : River Ragwort
Scientific name
Senecio sarracenicus
L.

The River ragwort ( Senecio sarracenicus ) even flow ragwort called, is a flowering plant in the family of the daisy family (Asteraceae).

description

illustration
Leaf margin with teeth bent forward.
Basket with eight ray-florets.

Vegetative characteristics

The river ragwort is a perennial herbaceous plant that reaches heights of 60 to 150, exceptionally up to 200 centimeters. The plant has a fleshy rhizome ; it also forms far-reaching root runners. The stem is pithy and filled with glandular hair in the upper section.

The leaves are undivided and bare; they have a lanceolate shape, being about five to six times as long as they are wide. This is a distinguishing feature to the marsh ragwort ( Senecio paludosus ), whose leaves are narrower, namely seven to fifteen times as long as they are wide. The foliage leaves of the river ragwort, which are half around the stem, are sharply serrated; the teeth are aligned towards the tip of the blade.

Generative characteristics

The flowering time is in late summer (August / September). The total inflorescence contains many cup-shaped partial inflorescences. The flower heads have a bell-shaped shell that is five-leaved on the outside. The flower heads contain tubular and ray florets . Of the latter there are usually seven or eight per flower heads; their color is golden yellow.

The number of chromosomes is 2n = 40.

ecology

The river ragwort is a hemicryptophyte . As an adaptation to the oxygen-poor swamp locations, the root bark has air-filled spaces, so it is a helomorphic species.

The pollination takes place by insects or by self-pollination. The seeds are spread by wind , adhesion (Velcro spread) and ants .

Occurrence and endangerment

The river ragwort is distributed subatlantic to subcontinental in parts of Europe and western Asia. River valleys are almost exclusively populated; in Germany especially those from the Weser , Leine , Elbe , Oder , Lower and Middle Rhine , Main and Danube . River ragwort is absent in the mountains and in southwest Germany. This rather rare European river valley plant occurs almost exclusively within near-natural sections of larger floodplains. Because of its long root runners, it acts as a pioneer plant and alluvial land fastener.

The river ragwort is a warmth-loving river valley plant that thrives on wet, at times flooded, nutrient-rich and base-rich, humus-rich, sandy-gravelly or purely clayey soils. It occurs preferentially in perennial fringing communities on the banks of rivers and oxbow lakes . It is the characteristic of the river common ground-herb society (Senecionetum fluviatilis Th. Müller ex Straka in Mucina 1993) from the association Senecion fluviatilis , which is endangered in Germany. The river ragwort is a root creep pioneer, a floodplain stabilizer and a light plant.

In Germany it is nationwide as “endangered” and in individual federal states the red list classification is often even higher (“endangered” or “threatened with extinction”). Regulatory measures in the habitats, such as straightening, building dykes, reinforcing banks and draining, are considered to be the main causes of population decline.

Taxonomy

The first publication was under the name ( Basionym ) Senecio sarracenicus by Carl von Linné . A synonym for Senecio sarracenicus L. is Senecio fluviatilis Wallr.

Sources and further information

literature

  • Henning Haeupler, Thomas Muer: picture atlas of the fern and flowering plants of Germany . Ed .: Federal Agency for Nature Conservation (=  The fern and flowering plants of Germany . Volume 2 ). Eugen Ulmer, Stuttgart (Hohenheim) 2000, ISBN 3-8001-3364-4 .
  • Heinz Ellenberg : Pointer values ​​of the vascular plants of Central Europe. - Scripta Geobotanica IX, Verlag Erich Goltze, Göttingen, 2nd, improved. 1979 edition.
  • Erich Oberdorfer : Plant-sociological excursion flora . - Ulmer Verlag, Stuttgart, 6th edition 1990, ISBN 3-8001-3454-3 .

Individual evidence

  1. ↑ a b c Werner Greuter: Compositae (pro parte majore). Senecio sarracenicus L. In: Werner Greuter, Eckhard von Raab-Straube (eds.): Compositae. at Euro + Med Plantbase - the information resource for Euro-Mediterranean plant diversity .
  2. ↑ a b c Erich Oberdorfer : Plant-sociological excursion flora for Germany and neighboring areas . With the collaboration of Angelika Schwabe and Theo Müller. 8th, heavily revised and expanded edition. Eugen Ulmer, Stuttgart (Hohenheim) 2001, ISBN 3-8001-3131-5 , pp.  954 .

Web links

Commons : Common Ragwort ( Senecio sarracenicus )  - Album with pictures, videos and audio files