Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

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

Cirsium ochrocentrum, Yellowspine Thistle

Lactuca serriola, Prickly Lettuce

Prickly Lettuce grows 12 to 24 inches (30-61 cm) tall or more; 3 feet (91 cm). plants are upright and spiny; milky sap is visible if stems or leaves are broken or cut. Lactuca serriola Prickly Lettuce is also called: China Lettuce, Compass Plant and Wild Lettuce. Lactuca serriola Prickly Lettuce has green leaves with variable shapes and sizes; leafy on the upper part of stem, leaves arranged alternately on stems. Lactuca serriola Prickly Lettuce leaves are prickly and clasping the stems as shown in photo; not also that the green leaves have small teeth and deeply cut lobes. Lactuca serriola Prickly Lettuce blooms from May to September across its wide introduced area. Preferred elevations from 1,000 to 7,000 feet (305-2,134 m). Preferred habitats include waste lands, roadsides, urban areas, sidewalks, alleys and disturbed areas. Lactuca serriola

Scientific Name: Lactuca serriola
Common Name: Prickly Lettuce

Also Called: China Lettuce, Compass Plant, Wild Lettuce

Family: Asteraceae, Sunflower

Synonyms: (Lactuca scariola, Lactuca scariola f. scariola, Lactuca scariola subsp. integrata)

Status: Introduced

Duration: Annual or biennial.

Size: 12 to 24 inches (30-61 cm) or more; 3 feet (91 cm)

Growth Form: Forb/herb; plants upright (erect) and spiny; milky sap visible if stems or leaves broken or cut; stems typically without surface ornamentation such as hairs, scales or bristles.

Leaves: Green leaves with variable shapes and sizes; leafy on the upper part of stem, leaves arranged alternately on stems; leaves prickly and clasping the stems as shown in photo above; leaves with small teeth and deeply cut lobes

Flower Color: Yellow or pale-yellow; several small heads clustered on tips of slender branching; flowers are modified ray florets only, called ligulate flowers, no disk florets; flowers about ½ inch (15 cm) wide; fruit is technically a cypsela with a white pappus.

Flowering Season: May to September

Elevation: 1,000 to 7,000 feet (305-2,134 m)

Habitat Preferences: Waste lands, roadsides, urban areas, sidewalks, alleys and disturbed areas.

Recorded Range: Throughout the United States and Canada. Also native to Baja California and northwest Mexico. In the southwestern part of the United States, Prickly Lettuce occurs in largest populations in AZ, CA, NM, NV and UT.

North America & US County Distribution Map for Lactuca serriola.

North America species range map for Prickly Lettuce Lactuca serriola:
North American range map courtesy of Virginia Tech, Dept. of Forest Resources & Environmental Conservation

North America species range map for Prickly Lettuce Lactuca serriola:  Click image for full size map.
Click image for full size map

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

  • Weeds of Kentucky and adjacent states: a field guide,
  • Weeds of the Northeast,
  • Weeds of Nebraska and the Great Plains,
  • Weeds of the United States and Canada,
  • Weeds of the West.
  • Plants included here may become weedy or invasive.

    Wetland Indicator: In North America Lactuca serriola has the following wetland designations:
  • Arid West, FACU
  • Atlantic and Gulf Coastal Plain, FAC;
  • Eastern Mountains and Piedmont, FAC;
  • Great Plains, FAC;
  • 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

    Invasive/Noxious Weed Information: Unknown
    Threatened/Endangered Information: Unknown

    Genus Information: 12 species in Lactuca throughout North America including Canada and Alaska. 5 species in various habitats in Arizona.

    Genus Information: In North America there are 13 species and 13 accepted taxa overall for Lactuca. Worldwide, The Plant List includes 147 accepted species names and a further 213 scientific names of infraspecific rank for the genus.

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

    In the Southwestern United States: Arizona has 5 species of Lactuca, California has 8 species, Nevada has 3 species, New Mexico has 8 species, Texas has 8 species, Utah has 5 species. Data approximate and subject to revision.

    Comments: Lactuca serriola is a naturalized weedy plant native to Europe that can be found in Arizona most anywhere in suitable habitat. It is similar, at least superficially so, to the Common Sowthistle, Sonchus oleraceus and to Spiny Sowthistle, Sonchus asper.

    Importance to Wildlife, Birds and Livestock
    Although Prickly Lettuce, Lactuca serriola is an introduced species, flowers, seeds and plants may be visited by hummingbirds and/or small mammals including rodents in search of food.

    Beneficial Value to Butterflies, Bees and Insects
    Although Prickly Lettuce, Lactuca serriola is an introduced species, its brightly colored flowers and plants may be visited by butterflies, moths and other insects in search of food and nectar.

    Etymology:
    The genus “Lactuca” (Lactu'ca:) a reference to (lac'ta:) which is Latin for “milk,” referring to the milky sap in stem, and a root word for lactic acid.

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

    The species epithet serriola (serrio'la:) either in ranks, or pertaining to salad, being one form of an old name for chicory.

    Ethnobotany
    Lactuca serriola has been used by Western American indigenous peoples.
  • Navajo, Ramah Drug, Ceremonial Medicine and Drug, Emetic; Compound decoction of plant used as a ceremonial emetic and Compound decoction of plant used as a ceremonial emetic.

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

    Date Profile Completed: 8/14/2014; updated 08/27/2020
    References:
    Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles
    U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database and USGS ITIS search - (accessed 08/27/20)
    https://plants.usda.gov/java/ClassificationServlet?source=profile&symbol=LACTU&display=31
    The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 08/27/20).
    http://www.theplantlist.org/1.1/browse/A/Compositae/Lactuca/
    David J. Keil #38; G. Ledyard Stebbins 2012, Lactuca serriola, in Jepson Flora Project (eds.) Jepson eFlora, /eflora/eflora_display.php?tid=3690, accessed on August 27, 2020.
    John L. Strother, FNA | Family List | FNA Vol. 19, 20 and 21 | Asteraceae, Lactuca, 9. Lactuca serriola Linnaeus, Cent. Pl. II. 29. 1756. Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford.
    T. Beth Kinsey, Southeastern Arizona Wildflowers and Plants; Lactuca serriola – Prickly Lettuce - accessed on August 27, 2020.
    https://www.fireflyforest.com/flowers/1371/lactuca-serriola-prickly-lettuce/
    Michael J. Plagens, Sonoran Desert Field Guide; Arizonensis - Prickly Lettuce, Lactuca serriola; - (accessed 08/27/20)
    http://www.arizonensis.org/sonoran/fieldguide/plantae/lactuca_serriola.html
    Wikipedia contributors, 'Lactuca serriola', Wikipedia, The Free Encyclopedia, 20 August 2020, 09:10 UTC,
    https://en.wikipedia.org/w/index.php?title=Lactuca_serriola&oldid=973968657 [accessed 27 August 2020]
    FNA 2006, Wiggins 1964, Kearney and Peebles 1969, Heil et al 2015, USDA GRIN; Editors: S.Buckley 2010, F.S.Coburn 2015, A.Hazelton 2015; from SEINet Field Guide, on-line; (accessed 08/27/20).
    https://swbiodiversity.org/seinet/taxa/index.php?taxon=2790&clid=3119
    SEINet synonyms, scientific names, geographic locations, general information.
    http://swbiodiversity.org/seinet/
    Etymology: Michael L. Charters California Plant Names: Latin and Greek Meanings and Derivations; A Dictionary of Botanical and Biographical Etymology - (accessed 08/25/20)
    http://www.calflora.net/botanicalnames/pageLA-LE.html
    http://www.calflora.net/botanicalnames/pageSA-SH.html