Rocket-leaf ragwort

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Rocket-leaf ragwort
Rocket-leaf ragwort (Jacobaea erucifolia)

Rocket-leaf ragwort ( Jacobaea erucifolia )

Systematics
Order : Astern-like (Asterales)
Family : Daisy family (Asteraceae)
Subfamily : Asteroideae
Tribe : Senecioneae
Genre : Jacobaea
Type : Rocket-leaf ragwort
Scientific name
Jacobaea erucifolia
( L. ) G. Gaertn. & al.

The rocket-leaf ragwort ( Jacobaea erucifolia , syn .: Senecio erucifolius L.), also called rocket-leaf ragwort , is a species of the genus Jacobaea within the sunflower family (Asteraceae). It particularly thrives in calcareous semi- arid grasslands .

description

illustration
Flower heads
Stems with leaves
Infructescence with pappus
Inflorescence with baskets: the outer bracts are mostly more or less from.
Basket with ripe achenes with pappus
The achenes of the ray florets are also short-haired.

Vegetative characteristics

The rocket-leaf ragwort is a perennial herbaceous plant and reaches heights of 30 to 120 centimeters. It forms runners . In the nominate form erucifolius , the central stem leaves are gray-green, pinnate, with lanceolate, usually narrow tips and without an accumulation of narrow leaf tips (ears) at the base. In the narrow-leaved subspecies Jacobaea erucifolia subsp. tenuifolia , the leaf sections are narrow-linear, rolled back at the edge and mostly fresh green on the underside.

Generative characteristics

There are numerous flower heads together in a single inflorescence. There are 13 bracts and 3 to 8 upright outer bracts that are about half as long as the bracts. The 13 ray-florets are light golden yellow.

All achenes have short hairs. The pappus is permanent.

The flowering period extends from July to September; where it occurs together with Jacob's ragwort , it blooms about six to eight weeks later than this.

The number of chromosomes is 2n = 40.

ecology

The rocket-leaf ragwort is a hemicryptophyte with a creeping rhizome . The pollination is carried out mainly by bees and flies. The diaspores , they are the achenes, are spread out by the wind (umbrella flyers).

Occurrence

This Eurasian species is partially absent in the north German lowlands . It often grows in limestone grasslands and pastures , in semi- arid grasslands or dry moorland meadows , on the edges of forests and bushes , on paths or cracks in the earth and in quarries . Rocket ragwort thrives best on base-rich , moderately nitrogen-rich loam soils . According to the Ellenberg pointer values , it is a light plant of sub-oceanic distribution and a dry pointer. The Raukenblättrige Ragwort is in Central Europe a weak association characteristic species of heat-vulnerable societies thistle (Onopordion acanthii). It occurs particularly often in semi-ruderal , disturbed societies of the associations Dauco-Melilotion, Convolvulo-Agropyrion or Mesobromion.

The rocket ragwort rises in the subspecies common rocket ragwort ( Jacobaea erucifolia subsp. Erucifolia ) in the Allgäu Alps in the Tyrolean part on the ascent to the Gaichtspitze up to an altitude of 1,300 meters.

Rocket-leaf ragwort ( Jacobaea erucifolia )

Systematics

The first publication took place in 1753 under the name ( Basionym ) Senecio erucifolius by Carl von Linné . It was placed in the Jacobaea genus in 1801 by Gottfried Gaertner , Bernhard Meyer and Johannes Scherbius in the Oekonomische Flora der Wetterau , Volume 3, 1, page 208.

From Jacobaea erucifolia there are several subspecies (selection):

  • Common rocket-leaf ragwort ( Jacobaea erucifolia (L.) G.Gaertn. & Al. Subsp. Erucifolia , Syn .: Senecio erucifolius L. subsp. Erucifolius )
  • Jacobaea erucifolia subsp. arenaria (Soó) B. North. & Greuter : It occurs in Ukraine, Romania, Bulgaria, Moldova, European Russia, Turkey and Transcaucasia.
  • Jacobaea erucifolia subsp. praealta (Bertol.) Greuter & B.Nord. (Syn .: Senecio praealtus Bertol. ): It occurs in Portugal, Spain and Italy.
  • Rosebay Hoary Ragwort ( Jacobaea erucifolia subsp. Tenuifolia (J.Presl & K.Presl) B.Nord & Greuter. , Syn .: Senecio erucifolius subsp. Tenuifolius (Jacq) JAV.. ): It is used in France, Corsica, Italy, in Switzerland, Germany, Croatia, Hungary, Bulgaria, Serbia, Romania, Slovakia and Ukraine.

Individual evidence

  1. ↑ a b 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.  955 .
  2. ↑ Erhard Dörr, Wolfgang Lippert : Flora of the Allgäu and its surroundings. Volume 2, IHW, Eching 2004, ISBN 3-930167-61-1 , p. 624.
  3. ↑ a b c d Werner Greuter (2006+): Compositae (pro parte majore). In: Werner Greuter, E. von Raab-Straube (Ed.): Compositae. : Datasheet Jacobaea erucifolia In: Euro + Med Plantbase - the information resource for Euro-Mediterranean plant diversity.

literature

  • Ruprecht Düll , Herfried Kutzelnigg : Pocket dictionary of plants in Germany. A botanical-ecological excursion companion to the most important species. 6th, completely revised edition. Quelle & Meyer, Wiebelsheim 2005, ISBN 3-494-01397-7 .
  • Michael Koltzenburg, Siegmund Seybold, Gabriele Zauner (eds.): Schmeil-Fitschen interactive. The comprehensive identification and information database . Verlag Quelle & Meyer, Wiebelsheim 2001, ISBN 3-494-01298-9 (1 CD-ROM).

Web links

Commons : Rockwort ( Jacobaea erucifolia )  - Collection of images, videos and audio files