Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

Home to the plants of the Sonoran, Chihuahuan and Mojave Deserts

Cirsium ochrocentrum, Yellowspine Thistle

Senecio vulgaris, Common Groundsel

Common Groundsel has showy yellow disk flowers in loose flat-topped clusters that bloom from February to July. Note Weevil in photograph climbing on and above distinctive Senecio phyllaries. Senecio vulgaris Common Groundsel has green leaves tapered to a stalk (petiole); leaves are ovate to oblanceolate and the margins are lobed as in the photograph. Senecio vulgaris Common Groundsel has 8 to 20 loose flat-topped flower heads, all discoid florets. Plants grow as weeds under general landscape watering needs but particularly in irrigated areas. Senecio vulgaris Common Groundsel is an introduced species from Eurasia, now naturalized throughout all of North America. Although mostly glabrous, young plants are covered with uneven dense soft white hairs (tomentose) as noted in the photograph. Senecio vulgaris

Scientific Name: Senecio vulgaris
Common Name: Common Groundsel

Also Called: Old-Man-In-The-Spring

Family: Asteraceae, Sunflower Family
Synonyms: ()

Status: Introduced and naturalized from Eurasia.

Duration: Annual, biennial from a shallow taproot.

Size: 8 to 20 inches (20-50 cm) or more

Growth Form: Forb/herb; plants may have 1 or more stems; without hair (glabrous) or slightly hairy; unevenly covered in dense, soft short hairs (tomentose) when young.

Leaves: Green; blade shape ovate to oblanceolate; edges or margins with lobes or teeth; upper (distal) leaves without stalk (petiole); leaves arranged alternately along stem.

Flower Color: Yellow; flower heads 8 or 10 to 20 or more clusters; disk florets; bracts surrounding flower heads (phyllaries) with extra set of black-tipped bracts (calyculi); fruit is a smooth or slightly hairy (dandelion-like plume) cypsela.

Flowering Season: February to July or later in cooler climes.

Elevation: Up to 4,000 feet (1,219 m)

Habitat Preferences: Grows as a weed in disturbed areas; ruderale areas, irrigated areas, farm lands.

Recorded Range: Common Groundsel is a common weed, a ruderale species found throughout all of North America, Europe and Asia.

North America & US County Distribution Map for Senecio vulgaris.

North America species range map for Common Groundsel, Senecio vulgaris:

North America species range map for Common Groundsel, Senecio vulgaris: Click image for full size map.
Click image for full size map

U.S. Weed Information: In North America name can be weedy or invasive according to the following authoritative sources:

  • State noxious weed lists for 46 states. State agriculture or natural resource departments;
  • Weeds of the Northeast;
  • Southeast Exotic Pest Plant Council;
  • Weeds of the West.

  • Plants included here may become weedy or invasive.

    U.S. Invasive/Noxious Weed Information: In North America Senecio vulgaris is listed as a Noxious Weed by the federal government and/or a State;
  • Washington State, Noxious Weed Control Board, Common Groundsel, Class C noxious weed.

  • Plants included here are invasive or noxious.

    International Invasive/Noxious Weed Information: *CABI, and *The Invasive Species Compendium (ISC) has identified Senecio vulgaris is listed as an “Invasive Species, Pest, Natural Enemy and Host Plant”. This species is a host plant the Cineraria leaf rust and for the fungus (Thielaviopsis basicola) that causes black root rot in fruits and vegetables.

    *CABI is The Centre for Agriculture and Bioscience International (CABI), Wallingford, Oxfordshire, England; The US Department of Agriculture is a lead partner with CABI.

    *ISC is The Invasive Species Compendium (ISC) is an encyclopedic resource that brings together a wide range of different types of science-based information to support decision-making in invasive species management worldwide.

    U.S. Wetland Indicator: In North America Senecio vulgaris has the following wetland designations:
  • Alaska, FACU
  • Arid West, FACU
  • Atlantic and Gulf Coastal Plain, UPL;
  • Eastern Mountains and Piedmont, FACU;
  • Great Plains, FACU;
  • Midwest, UPL;
  • Northcentral & Northeast, FACU;
  • Western Mountains, Valleys, and Coast, FACU;

  • FACU = Facultative Upland, usually occur in non-wetlands, but may occur in wetlands
    UPL = Obligate Upland, almost never occur in wetlands

    U. S. Threatened/Endangered Information: Unknown

    Genus Information: In North America there are 71 species for Senecio. Worldwide, The Plant List includes 1,587 accepted species names and a further 871 scientific names of infraspecific rank for Senecio.

    The genus Senecio was published in 1753 by Carl Linnaeus, (1707-1778).

    In the Southwestern United States: Arizona has 13 species of Senecio, California has 25 species, Nevada has 15 species, New Mexico has 22 species, Texas has 9 species, Utah has 18 species. Data approximate and subject to revision.

    Comments: Common Groundsel is a weed that spreads rapidly because of its ability to develop hundreds or several thousands of wind-borne seeds per plant and they may have 3 or more generations per season. According to the University of California, Common Groundsel was also one of the first weed species to have populations develop resistance to some common agricultural herbicides.

    The genus Senecio is known to contain alkaloids which may cause irreversible liver damage and possibly death. It is poisonous to cattle and horses and toxic to humans.

    In Southwest Desert Flora also see Lemmon's Ragwort, Senecio lemmonii, Threadleaf Ragwort, Senecio flaccidus var. flaccidus, Smooth Threadleaf Ragwort, Senecio flaccidus var. monoensis and Threadleaf Groundsel, Senecio flaccidus.

    Importance to Wildlife, Birds and Livestock
    Senecio vulgaris has small but attractive tubular flowers and the flowers and their seeds and plants may be visited by hummingbirds and/or small mammals including rodents and granivorous birds in search of nectar or food.

    Beneficial Value to Butterflies, Bees and Insects
    Senecio vulgaris has small but attractive tubular flowers and the flowers and their plants may be visited by butterflies, moths, native bees and other insects in search of food and nectar.

    The genus “Senecio” (Sene'cio:) from senex, "old man," referring to the gray hairs on the seeds.

    The genus Senecio was published in 1753 by Carl Linnaeus, (1707-1778).

    The species epithet vulgaris (vulgar'is:) means lacking good taste, vulgar and common.

    The taxon Senecio vulgaris was published in 1753 by Carl Linnaeus, (1707-1778).


    Date Profile Completed: 05/08/2017; updated 10/31/2020
    Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles, California.
    U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database and USGS ITIS search; accessed 10/25/2020.
    The Plant List (2013). Version 1.1. Published on the Internet;; accessed 10/25/2020.
    Theodore M. Barkley†, FNA| Family List | FNA Vol. 20 | Asteraceae | Senecio; 37. Senecio vulgaris Linnaeus, Sp. Pl. 2: 867. 1753.; Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford.
    Debra K. Trock 2012, Senecio vulgaris, in Jepson Flora Project (eds.) Jepson eFlora, /eflora/eflora_display.php?tid=4866, accessed on October 31, 2020.
    FNA 2006, Trock 2014 (Jepson Online), Kearny and Peebles 1979; Editors: A.Hazelton 2015; from SEINet Field Guide, on-line; accessed 10/31/2020.
    C. A. Wilen, UC Statewide IPM Program, San Diego County; University of California Agriculture & Natural Resources - Statewide Integrated Pest Management Program IPM (accessed 10/31/2020).
    Cornell University, College of Agriculture and Life Sciences; accessed 10/31/2020.
    CABI, 2020. Senecio vulgaris. In: Invasive Species Compendium. Wallingford, UK: CAB International.
    Wikipedia contributors, 'Senecio vulgaris', Wikipedia, The Free Encyclopedia, 17 October 2020, 07:15 UTC, [accessed 31 October 2020]
    Wikipedia contributors, 'Thielaviopsis basicola', Wikipedia, The Free Encyclopedia, 27 October 2020, 18:29 UTC, [accessed 31 October 2020]
    Seiler, John, Peterson, John, North American species range map courtesy of Virginia Tech, Dept. of Forest Resources & Environmental Conservation
    SEINet synonyms, scientific names, geographic locations, general information.
    Etymology:Michael L. Charters California Plant Names: Latin and Greek Meanings and Derivations; A Dictionary of Botanical and Biographical Etymology - (accessed 10/24/2020, 10/31/2020)
    IPNI (2020). International Plant Names Index. Published on the Internet, The Royal Botanic Gardens, Kew, Harvard University Herbaria & Libraries and Australian National Botanic Gardens. [Retrieved 25 October 2020 and 31 October 2020].
    https:// /a/12653-1