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Jacobaea vulgaris Gaertn.

Overview
General Information
ID Info
Similar Species
Need ID Help?
Aperçu
Renseignements Généraux
Informations D'identification
Espèces Semblables
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Family :

Famille :

Asteraceae

Synonym(s) :

Synonyme(s) :

Senecio jacobaea L.

Common Name(s) :

Nom(s) commun(s) :

Tansy ragwort
(English) (GC 2016)
Séneçon jacobée (French) (GC 2016)
Stinking-willie (English) (Darbyshire 2003)
Hierba lombriguera (Spanish) (CABI 2020)
Herb St. Jacques (French) (CABI 2020)
Krestovnik yakova (Russian) (CABI 2020)
Tasna (Portuguese) (CABI 2020)

Tansy ragwort (Jacobaea vulgaris); achenes

  • Tansy ragwort (Jacobaea vulgaris); achenes

  • Tansy ragwort (Jacobaea vulgaris); achenes

  • Tansy ragwort (Jacobaea vulgaris); achene

  • Tansy ragwort (Jacobaea vulgaris); achene

  • Tansy ragwort (Jacobaea vulgaris) achene, collar (top-down view)

  • Tansy ragwort (Jacobaea vulgaris) achene, collar (side view)

  • Jacobaea vulgaris seed head, achenes, and immature achenes

Explore More :

Explore plus :

CABI

Overview

Aperçu

Regulation :

Remarques Réglementation:

  • CFIA Weed Seeds Order - Class 2: Primary Noxious Weed Seeds
  • Quarantine lists of countries e.g. India *may be updated without notice

Regulation Notes:

Distribution :

Répartition :

Native to northern Africa, Europe and temperate Asia and introduced in North America, China, Australia, New Zealand, and beyond its native range in Europe (Finland, Norway, Russia) (USDA-ARS 2020). In the United States, it occurs mostly in the west and northeastern regions (Kartesz 2015). Occurs in Canadian provinces of British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island, Quebec, (Brouillet et al. 2010+).

Habitat and Crop Association :

Habitat et Cultures Associées :

Pastures, hay fields, old fields, roadsides, railway lines and disturbed areas (Bain 1991; Darbyshire 2003). Not a known weed of crops, however a problem in pastures due to toxicity (Royer and Dickinson 1999).

Economic Use, cultivation area, and Weed Association :

Utilisation économique, zone de culture et association de mauvaises herbes :

Duration of Life Cycle :

Durée du cycle vital:

Biennial or Perennial

Dispersal Unit Type :

Type d’unité de dispersion :

Achene

General Information

RENSEIGNEMENTS GÉNÉRAUX

Jacobaea vulgaris is thought to have been introduced into Canada in the 1850s in ship ballast (Bain 1991). J. vulgaris contains alkaloids which are toxic to cattle, deer, horses and goats (Royer and Dickinson 1999).

A single plant can produce as many as 150,000 seeds, which can remain viable for over 20 years (BC MAFF 2002). The achenes from disc florets have both a pappus and hairs for wind and animal dispersal, and the ray achenes are heavier, without dispersal mechanisms, and stay in the flower head for months after maturity (CABI 2020).

.

Jacobaea vulgaris infestation (Leslie J. Mehrhoff, University of Connecticut, Bugwood.org)

Identification

Identification

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  • Dimorphic Achene: achene with pappus

    Size

    • Achene length*: 1.2 – 2.0 mm; width: 0.4 – 0.7 mm
    *Note: minimum and maximum of 20 achenes in a normal range of this species using image measurement (ISMA 2020)

    Shape

    • Achene cylindrical, straight or slightly curved longitudinally, tapered at one end, the other truncate

    Surface Texture

    • Achene surface is stippled with sparse, short, yellow hairs between several longitudinal, wide ribs

    Colour

    • Achene is shining light yellow or yellow brown, may be the same colour or reddish-brown between the ribs

    Other Features

    Pappus

    • A persistent pappus of thin, white bristles up to 6.0 mm (eFloras 2020) may be attached to the achene, and is removed during processing (CABI 2020)

    Achene end with pappus

    • The achene is constricted below the rim of the truncate end, making this end appear flared out
    • A short style remnant is at the center of the truncate end, generally not visible from side view

    Achene end without pappus

    • A small ring of tissue is at the center of this end 

    Tansy ragwort (Jacobaea vulgaris); achenes

  • Dimorphic Achene: achene without pappus

    Size

    • Achene length*: 1.2 – 2.0 mm; width: 0.4 – 0.7 mm
    *Note: minimum and maximum of 10 achenes in a normal range of this species using image measurement (ISMA 2020)

    Shape

    • Achene cylindrical, straight or slightly curved longitudinally tapered at one end, the other is truncate

    Surface Texture

    • Achene surface is stippled, without hairs and several longitudinal, wide ribs

    Colour

    • Achene is shining light yellow or yellow brown, can be the same colour or reddish-brown between the ribs

    Other Features

    Pappus

    • A pappus of thin, white bristles up to 6.0 mm may be attached to immature achenes, but does not persist on mature achenes (eFloras 2020)

    Achene end with pappus

    • The achene is constricted below the rim of the truncate end, making this end appear flared out
    • A short style remnant is at the center of the truncate end, generally not visible from side view

    Achene end without pappus

    • A small ring of tissue is at the end attached to the flower head

    Tansy ragwort (Jacobaea vulgaris); achenes

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  • Seed

    Size

    • Seed size similar to achene size

    Shape

    • Seed is oblong

    Surface Texture

    • Seed is smooth

    Colour

    • Seed is grey

    Other Features

    • Seed coat thin, whitish coloured, adhering to the fruit wall
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>

  • Embryo

    Size

    • Embryo fills the seed

    Shape

    • Embryo is spatulate, axial position

    Endosperm

    • Endosperm absent, nutritive tissue stored in the cotyledons

    Other Features

    • Cotyledons are soft-textured

Identification Tips

CONSEILS POUR L’IDENTIFICATION

Achenes of Jacobaea vulgaris can be distinguished from other Jacobaea species and Senecio species by their yellowish brown colour, wider achenes, and the short, yellow and more sparse surface hairs than the other species.

Tansy ragwort (Jacobaea vulgaris); achenes

Additional Botany Information

AUTRES RENSEIGNEMENTS BOTANIQUES

Flowers/Inflorescence

  • Flowers yellow, daisy-like with both disc and ray florets
  • The achenes with a pappus are more commonly encountered than the achenes without a pappus from the florets around the outside of the flower head (eFloras 2020)

Jacobaea vulgaris inflorescence (Leslie J. Mehrhoff, University of Connecticut, Bugwood.org)

Similar Species

ESPÈCES SEMBLABLES

Similar species are based on a study of seed morphology of various species, and those with similar dispersal units are identified. The study is limited by physical specimen and literature availability at the time of examination, and possibly impacted by the subjectivity of the authors based on their knowledge and experience. Providing similar species information for seed identification is to make users aware of similarities that could possibly result in misidentification.

Jacobaea maritima (L.) Pelser & Meijden (dusty miller)

J. maritima achenes are generally longer (length*: 1.8 – 2.8 mm; width: 0.5 – 1.0 mm), without surface hairs and do not have a flared pappus end compared to J. vulgaris achenes. The achene is dark brown between the ribs, rather than the same colour or reddish brown colour in J. vulgaris.

*Note: minimum and maximum of 10 achenes in a normal range of this species using image measurement (ISMA 2020)

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Reference(s)

Référence(s)

Bain, J. F. 1991. The biology of Canadian weeds. 96. Senecio jacobaea L. Canadian Journal of Plant Science 71: 127-140.

British Columbia Ministry of Agriculture, Food and Fisheries (BC MAFF). 2002. Guide to weeds in British Columbia. Open Learning Agency, Burnaby, British Columbia, Canada. 195 pp.

Brouillet, L., Coursol, F., Meades, S. J., Favreau, M., Anions, M., Bélisle, P. and Desmet, P. 2010+. VASCAN, the database of vascular plants of Canada. http://data.canadensys.net/vascan/ Accessed November 23, 2020.

Centre for Agriculture and Bioscience International (CABI). 2020. Invasive Species Compendium, CAB International, Wallingford, UK. https://www.cabidigitallibrary.org/journal/cabicompendium Accessed November 23, 2020.

Darbyshire, S. J. 2003. Inventory of Canadian Agricultural Weeds. Agriculture and Agri-Food Canada, Research Branch. Ottawa, ON.

eFloras. 2020. Electronic Floras. Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA., http://www.efloras.org Accessed August 19, 2020.

Flora of North America (FNA) Editorial Committee, eds. 1993+. Flora of North America North of Mexico [Online]. 22+ vols. New York and Oxford.  Accessed December 29, 2022.

Global Biodiversity Information Facility (GBIF) Secretariat. 2022. https://doi.org/10.15468/39omei Accessed via https://www.gbif.org/species/5388602 Accessed December 29, 2022.

Government of Canada (GC). 2016. Canadian Weed Seeds Order. https://laws-lois.justice.gc.ca/eng/regulations/SOR-2016-93/page-2.html (English) https://laws-lois.justice.gc.ca/fra/reglements/DORS-2016-93/page-2.html (French)

International Seed Morphology Association (ISMA). 2020. Method for Seed Size Measurement. Version 1.0. ISMA Publication Guide.  https://www.idseed.org/authors/details/method_for_seed_size_measurement.html

Kartesz, J. T. 2015. The Biota of North America Program (BONAP). North American Plant Atlas. Chapel Hill, N.C., www.bonap.org/MapSwitchboard.html Accessed November 23, 2020.

Royer, F. and Dickinson, R. 1999. Weeds of Canada and the Northern United States. The University of Alberta Press/Lone Pine Publishing, Edmonton, Alberta.

U.S. Department of Agriculture-Agricultural Research Services (USDA-ARS). 2020. Germplasm Resources Information Network (GRIN), https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysimple.aspx Accessed November 23, 2020.

Author(s)

AUTEUR(S)

Jennifer Neudorf, Angela Salzl, Ruojing Wang, Karen Castro, Katrina Entwistle

Canadian Food Inspection Agency