Summary ⁵

Lactuca serriola, also called prickly lettuce, milk thistle, compass plant, and scarole, is an annual/biennial plant in the daisy family. It has a somewhat unpleasant odor and is commonly considered a weed.

Botanical Information ⁶

Lactuca serriola, otherwise known as wild lettuce, is a flowering plant that grows throughout North America, where it was introduced. Wild lettuce has small yellow florets that are 1-1.5 cm wide made of 12-20 ray flowers. It produces seeds called achenes that are grey-tipped with bristles. Wild lettuce can grow from 2 to 4 feet tall. It has prickly leaves that are progressively smaller moving up the stem. You can see little comb-like spines that grow from the veins and leaf edges. Another notable characteristic of prickly lettuce is milky white sap in its stems, leaves and roots.

Ecological Information ⁷

Lactuca serriola came to America as an agricultural weed and is native to Europe, Asia, and Africa. It is widespread in places below 7,500 ft elevation and is commonly encountered in the Southwest U.S. It typically grows in dry or moist, sandy soils though it can even be seen growing through cracks in the sidewalk! Prickly lettuce can easily hybridize with cultivated lettuce (Lactuca sativa) so farmers harvesting seeds of this plant should beware.

Ethnobotanical Information ⁸

Prickly lettuce has edible as well as medicinal qualities. Its young leaves can be eaten and are a nice addition to salads. Components of the plant especially concentrated in the milky white sap are relaxing to the nervous system and smooth muscle. Medicinally it can be used as a nervine, analgesic, and antispasmodic. Therefore, it has been used to treat insomnia, restlessness, mild pain, and couching.

References ⁹

Whitson, Tom, Larry C Burrill, Steven A Dewey, B.E. Nelson, Richard D Lee,
Robert Parker, Daniel A Bell, Dave Cudney, Steven A Dewey, Clyde L
Elmore, Rodney G Lym, Don W Morishita, Robert Parker, Dean G Swan,
Tom D whitson, Richard K Zollinger. (2009). Weeds of the West.
The Western Society of Weed Science, Western United States Land
Grant Universities. Jackson, WY.

Dara, Saville. (2021). The Ecology of Herbal Medicine, A Guide to Plants and Living Landscapes of the American Southwest. (p.) Albuquerque, New Mexico. University of New Mexico Press.

Moore, Michael. (1989). Medicinal Plants of the Desert and Canyon West. (p.). Santa Fe, New Mexico. Museum of New Mexico Press.

Bosque Field Guide
Cartron, Lightfoot, Mygatt, Brantley, Lowrey. (2008). A Field Guide to the Plants and Animals of the Middle Rio Grande Bosque. (p. 63). New Mexico, University of New Mexico Press.

Moore, Michael. (1941). Medicinal Plants of the Canyon West. Museum of New
Mexico Press. Santa Fe, NM.

Thayer, Samuel. (2010). Natures Garden. Foragers Harvest Press. Birchwood,
WI.

About the Author ¹⁰

Student author(s)*: Jonas (age 12) from Homeschool Science Coop

*The entries in this field guide have been edited by Yerba Mansa Project staff to ensure that they contain quality, fact-checked content and standardized formatting. https://yerbamansaproject.org/

Sources and Credits

1. (c) Andreas Rockstein, some rights reserved (CC BY-SA), https://www.flickr.com/photos/74738817@N07/40885960900/
2. (c) albuquerqueherbalism, all rights reserved
3. (c) Andreas Rockstein, some rights reserved (CC BY-SA), https://www.flickr.com/photos/74738817@N07/41488706795/
4. (c) Andreas Rockstein, some rights reserved (CC BY-SA), https://www.flickr.com/photos/74738817@N07/36039135156/
5. Adapted by caseynm from a work by (c) smiller33, some rights reserved (CC BY-SA)
6. Adapted by albuquerqueherbalism from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Lactuca_serriola
7. Adapted by albuquerqueherbalism from a work by (c) smiller33, some rights reserved (CC BY-SA)
8. Adapted by Hannah from a work by (c) smiller33, some rights reserved (CC BY-SA)
9. Adapted by Hannah from a work by (c) caseynm, some rights reserved (CC BY-SA)
10. Adapted by albuquerqueherbalism from a work by (c) caseynm, some rights reserved (CC BY-SA)

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