Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

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

Cirsium ochrocentrum, Yellowspine Thistle

Medicago polymorpha, Burclover

Burclover has small but pretty yellow flowers that extend from stem axils and cluster into heads at stem tips. Plants blooms from March to June or July. Medicago polymorpha Burclover is also called Burr Medic, California Burclover, Toothed Bur Clover and Toothed Medick. Plants are considered weedy in many areas.  Medicago polymorpha Burclover fruits are smooth, brown coiled pods with 2 to 6 turns and 2 to 3 rows of prickles which often have tiny hooks on the ends.  Medicago polymorpha Burclover are widely established plants native to Europe and naturalized in the United States and Canada.  Medicago polymorpha Burclover prefer elevations below 5,000 feet (1,500 m) and grow in chaparral, oak woodland, streambanks, roadsides, disturbed areas, fields, grasslands, pastures, agricultural lands (especially alfalfa fields) and lawns. Medicago polymorpha

Scientific Name: Medicago polymorpha
Common Name: Burclover

Also Called: Bur-clover, Burr Medic, California Burclover, Toothed Bur Clover, Toothed Medick

Family: Fabaceae or Leguminosae Family

Synonyms: (Medicago apiculata, Medicago denticulata, Medicago hispida, Medicago hispida var. apiculata, Medicago hispida var. confinis, Medicago hispida var. lappacea, Medicago hispida var. nigra, Medicago lappacea, Medicago polycarpa, Medicago polymorpha f. apiculata, Medicago polymorpha var. brevispina, Medicago polymorpha var. ciliaris, Medicago polymorpha var. polygyra, Medicago polymorpha var. tricycla, Medicago polymorpha var. vulgaris)

Status: Burclover was introduced to North America from the Mediterranean basin and now naturalized and widely established throughout the world.

Duration: Annual or perennial; plants laying flat on the ground and mat-forming with multiple branches.

Size: May grow more then 2 feet (60 cm) long, tends to travel along substrate, horizontally or vertically.

Growth Form: Burclover is a forb/herb; it is common and widely established.

Leaves: Burclover has green compound leaves that are divided into three round leaflets.

Flower Color: Burclover has small bright yellow flowers clustered into heads on stem tips; the fruit is a brown legume pod which has prickles as shown in the photo above.

Flowering Season: March to June or July

Elevation: Below 5,000 feet (1,500 m).

Habitat Preferences: chaparral vegetation, oak woodland, streambanks, roadsides, disturbed areas, fields, lawns, grasslands, pastures, agricultural lands (especially alfalfa fields) and lawns.

Recorded Range: Widespread throughout the southern, western and eastern shoreline, it is also found in Alaska and most of Canada.

North America & US County Distribution Map for Medicago polymorpha.

North America species range map for Burclover, Medicago polymorpha:

North America species range map for Burclover, Medicago polymorpha:
Click image for full size map.

U.S. Weed Information: See U.S. and international noxious and invasive weed information below.

U.S. Wetland Indicator: In North America Medicago polymorpha has the following wetland designations:

  • Alaska, FACU
  • Arid West, FACU
  • Atlantic and Gulf Coastal Plain, FACU;
  • Eastern Mountains and Piedmont, FACU;
  • Great Plains, FACU;
  • Hawaii, UPL
  • Midwest, FACU;
  • Northcentral & Northeast, FACU;
  • Western Mountains, Valleys, and Coast, FACU;

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

    U.S. Invasive/Noxious Weed Information: In North America, according to, (Invasive and Exotic Species of North America), Medicago polymorpha is listed as an invasive species by the following authorities:
  • Alaska Exotic Plant Information Clearinghouse
  • California Invasive Plant Council
  • Nonnative Invasive Species in Southern Forest and Grassland Ecosystems

  • International Invasive/Noxious Weed Information: 1The Centre for Agriculture and Bioscience International, (CABI), and 2The Invasive Species Compendium (ISC) has identified Medicago polymorpha as an “Invasive Species, Pest and Host Plant”; it is native to western and central Asia and countries around the Mediterranean, and has been introduced widely around the world.

    1The Centre for Agriculture and Bioscience International (CABI), Wallingford, Oxfordshire, England; The US Department of Agriculture is a lead partner with CABI.

    2The 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.

    Threatened/Endangered Information: Unknown

    Genus Information: In North America, USDA Plants Database lists 39 species for Medicago. Worldwide, World Flora Online includes 134 accepted names and The Plant List has 121 records for Medicago which includes sub-species and varieties.
    The genus Medicago was first published in 1753 by Carl Linnaeus, (1707-1778).

    In the Southwestern United States: Arizona has 4 species of genus, California has 7 species, Nevada, New Mexico and Utah each have 3 species and Texas has 6 species. Data approximate, subject to revision.

    Comments: Burclover is an annual broad-leaf species, a weedy herb that is originally from Europe. It is now naturalized and common where found. Plants are weedy and well adapted to disturbed- and waste-areas. Livestock forage on the plant and may be grown for pasture or a cover crop.

    The fruit, a nasty bur is spread around as it clings to clothing or fur.

    In Southwest Desert Flora also see Alfalfa, Medicago sativa.

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

    Medicago polymorpha is decent forage for livestock with the exception of horses and mules.

    Beneficial Value to Butterflies, Honey Bees and Insects
    Burclover, Medicago polymorpha has attractive flowers, the flowers and their plants may be visited by butterflies, moths, flies, honeybees, Native Bees and other insects in search of food and nectar.

    Medicago polymorpha is an adult food source for;
  • Erynnis funeralis, Funereal Duskywing;
  • Colias philodice, Common sulphur;
  • Colias eurytheme, Orange Sulphur;
  • Glaucopsyche lygdamus, Silvery Blue.

  • Find out more from Butterflies and Moths of North America, (BAMONA).

    U.S.D.A. Natural Resources Conservation Center, Plant Guide;
    The USDA, Natural Resources Conservation Service Plant Guide has a comprehensive, excellent information on-line guide regarding this invasive species. Click here for the information.

    The genus “Medicago” is from the Greek word "Medlick" or "medick" meaning alfalfa and the species epithet polymorpha means many forms or variable.
    The genus Medicago was first published in 1753 by Carl Linnaeus, (1707-1778).

    The species epithet polymorpha

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

    Ethnobotany - Native American Ethnobotany; University of Michigan - Dearborn
    Burclover, Medicago polymorpha is used for such purposes as described below.
  • Cahuilla Food, Porridge, Parched, ground seeds used to make mush.
  • Mendocino Indian Food, Forage, Dried seed pods eaten by sheep in summer.
  • Mendocino Indian Food, Forage, Seeds and leaves used as a forage plant.

  • See complete listing of ethno-botanical uses at Native American Ethnobotany, University of Michigan, Dearborn.

    Date Profile Completed: 10/28/2019; updated 02/14/2022
    References and additional information:
    Kearney, Thomas H., Peebles, Robert H., 1960, Arizona Flora, University of California Press, Berkley and Los Angeles, California; as Medicago hispida var. confinis.; Department of Agriculture, Natural Resources Conservation Service on-line database and USGS ITIS search; accessed on-line; 02/11/2022.
    World Flora Online; A Project of the World Flora Online Consortium; An Online Flora of All Known Plants - (accessed on-line; 02/11/2022)
    The Plant List (2013). Version 1.1. Published on the Internet; (accessed on-line; 02/19/2022).; California burclover, Medicago polymorpha - (accessed on-line; 02/11/2022).
    Clark, Shawnna, 2014. Plant guide for bur clover (Medicago polymorpha L.); USDA-Natural Resources Conservation Service, Big Flats Plant Materials Center, Corning New York - (accessed on-line; 02/11/2022).
    Native Plant Information Network, NPIN. Published on the Internet; accessed 02/14/2022. Lady Bird Johnson Wildflower Center at The University of Texas, Austin, TX.
    University of California Agriculture & Natural Resources - Statewide Integrated Pest Management Program IPM (accessed 02/11/2022).
    Martin F. Wojciechowski & Duane Isely 2012, Medicago polymorpha, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on February 11, 2022.
    Wikipedia contributors. "Medicago polymorpha." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 11 Mar. 2021. Web. 11 Feb. 2022.
    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 02/12/2022)
    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 on-line; 12 February 2022].