1. Family: Montiaceae Raf.
    1. Genus: Lewisia Pursh
      1. Lewisia rediviva Pursh

        Bitterroot is a small plant with white to purplish pink flowers. The species name, rediviva, means 'brought back to life' and refers to this plant's ability to sprout new growth, even after long periods of drought.

    [KSP]

    Kew Species Profiles

    General Description
    Bitterroot was first described as new to science in 1813 from specimens collected during one of the first western expeditions across the United States to the Pacific coast, but the species was already well-known and used by local Native Americans.

    Bitterroot is a small plant with white to purplish pink flowers. The species name, rediviva, means 'brought back to life' and refers to this plant's ability to sprout new growth, even after long periods of drought.

    The genus name, Lewisia, commemorates Captain Meriweather Lewis, one of the leaders of the famous Lewis and Clark Expedition that crossed the Rocky Mountains to reach the west coast of the USA (1804-1806). The plants discovered by Lewis and Clark were already well-known to Native Americans in the area, and eaten by local people. Today, bitterroot is the state flower of Montana and has given its name to the Bitterroot Range, which runs north-south and forms the divide between Idaho and Montana.

    Species Profile
    Geography and distribution

    Occurs in the western United States and Canada, from southern California to British Columbia and east into Wyoming and Colorado.

    The habitat of Lewisia rediviva has a dry climate, with a long cool growing season, with most of the annual precipitation often falling as snow.

    Description

    Bitterroot is a low-growing perennial with succulent, fleshy leaves, up to 5 cm long but only 2-3 mm wide. The plant dies down for the dry summer. The leaves are held in a rosette and are either evergreen or die back to the thick fleshy roots.

    The solitary, silky flowers, are up to 7.5 cm wide, and held on short stems. They are composed of 4-9 papery sepals and 12-20 petals surrounding a bunch of stamens. The flowers can be white, but shades of rose or purplish pink are more common. They open in late spring and, after withering, become detached and blow along the ground, dispersing their seeds.

    There are two varieties: Lewisia rediviva var. minor and L. rediviva var. rediviva . The former occurs in the mountains of Nevada and southern California and is distinguished by its smaller flowers.

    Threats and conservation

    The conservation status of bitterroot is classified as 'Secure' (G5) according to the NatureServe Conservation Status Ranks.

    Uses

    The common name bitterroot refers to the taste of the roots, which are cooked and eaten by Native Americans. The species is also used by several Native American groups as a medicinal plant for sore throats, heart and pleurisy pain, and to increase milk flow after childbirth.

    Lewisia rediviva is cultivated as an ornamental.

    An extraordinary observation

    A remarkable story is told by Sir William Hooker in Curtis's Botanical Magazine : 'The specimen from which our figure was taken at Kew… when gathered with a view of being preserved for the Herbarium... was immersed in boiling water on account of its well-known tenacity of life. More than a year and a half after, it notwithstanding showed symptoms of vitality and produced its beautiful flowers in great perfection in May of the present year [1863] in the Royal Gardens of Kew.'

    Millennium Seed Bank: Seed storage

    Kew's Millennium Seed Bank Partnership aims to save plant life world wide, focusing on plants under threat and those of most use in the future. Seeds are dried, packaged and stored at a sub-zero temperature in our seed bank vault.

    Description of seeds: Average 1,000 seed weight = 2.28 g

    Number of seed collections stored in the Millennium Seed Bank: One

    Germination testing: 55% germination was achieved on a 1% agar medium, at 5°C, on a cycle of 8 hours daylight/16 hours darkness

    This species at Kew

    Bitterroot can be seen growing in the Davies Alpine House at Kew.

    Spirit-preserved specimens of  Lewisia rediviva are held in Kew's Herbarium, where they are made available to researchers, by appointment. The details of some of these specimens can be seen online in the Herbarium Catalogue. 

    Roots of  Lewisia rediviva are held in Kew's Economic Botany Collection, where they are available to researchers, by appointment.

    Distribution
    Canada, USA
    Ecology
    Exposed sandy or rocky places, and on screes at altitudes of 1,300 - 3,000 m.
    Conservation
    NatureServe Status: G5 - Secure
    Hazards

    None known.

    [KSP]
    Use
    Food, medicinal, ornamental.

    Images

    Distribution

    Native to:

    Alberta, Arizona, British Columbia, California, Colorado, Idaho, Montana, Nevada, Oregon, Utah, Washington, Wyoming

    Common Names

    English
    Bitterroot

    Lewisia rediviva Pursh appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    51035.000

    First published in Fl. Amer. Sept. 2: 368 (1813)

    Accepted by

    • Ackerfield, J. (2015). Flora of Colorado: 1-818. BRIT Press.
    • Flora of North America Editorial Committee (2003). Flora of North America North of Mexico 4: 1-559. Oxford University Press, New York, Oxford.

    Literature

    Kew Species Profiles
    • Wilford, R. (2010). Alpines from Mountains to Gardens. Royal Botanic Gardens, Kew.
    • Moerman, D.E. (2009). Native American Medicinal Plants. Timber Press, Portland
    • Hooker, W.J. (1863). Lewisia rediviva. Curtis's Bot. Mag. 89: Plate 5395.
    • NatureServe – Lewisia rediviva.
    Kew Backbone Distributions
    • Ackerfield, J. (2015). Flora of Colorado: 1-818. BRIT Press.
    • Flora of North America Editorial Committee (2003). Flora of North America North of Mexico 4: 1-559. Oxford University Press, New York, Oxford.

    Sources

    Art and Illustrations in Digifolia
    Digital Image © Board of Trustees, RBG Kew

    Herbarium Catalogue Specimens
    'The Herbarium Catalogue, Royal Botanic Gardens, Kew. Published on the Internet http://www.kew.org/herbcat [accessed on Day Month Year]'. Please enter the date on which you consulted the system.

    Kew Backbone Distributions
    The International Plant Names Index and World Checklist of Selected Plant Families 2019. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    Kew Names and Taxonomic Backbone
    The International Plant Names Index and World Checklist of Selected Plant Families 2019. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    Kew Species Profiles
    Kew Species Profiles
    http://creativecommons.org/licenses/by-nc-sa/3.0