Lactuca serriola - L.
Prickly Lettuce
Other Common Names: prickly lettuce
Synonym(s): Lactuca scariola L.
Taxonomic Status: Accepted
Related ITIS Name(s): Lactuca serriola L. (TSN 36608)
French Common Names: laitue scariole
Unique Identifier: ELEMENT_GLOBAL.2.153155
Element Code: PDAST5F090
Informal Taxonomy: Plants, Vascular - Flowering Plants - Aster Family
Kingdom Phylum Class Order Family Genus
Plantae Anthophyta Dicotyledoneae Asterales Asteraceae Lactuca
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Concept Reference
Concept Reference: Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Concept Reference Code: B94KAR01HQUS
Name Used in Concept Reference: Lactuca serriola
Conservation Status

NatureServe Status

Global Status: GNR
Global Status Last Changed: 22Mar1994
Rounded Global Status: GNR - Not Yet Ranked
Nation: United States
National Status: NNA
Nation: Canada
National Status: NNA (03Nov2017)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Alabama (SNA), Arizona (SNA), Arkansas (SNA), California (SNA), Colorado (SNA), Connecticut (SNA), Delaware (SNA), District of Columbia (SNA), Florida (SNA), Georgia (SNR), Hawaii (SNA), Idaho (SNA), Illinois (SNA), Indiana (SNA), Iowa (SNA), Kansas (SNA), Kentucky (SNA), Louisiana (SNA), Maine (SNA), Maryland (SNA), Massachusetts (SNR), Michigan (SNA), Minnesota (SNA), Mississippi (SNA), Missouri (SNA), Montana (SNA), Nebraska (SNA), Nevada (SNA), New Hampshire (SNA), New Jersey (SNA), New Mexico (SNA), New York (SNA), North Carolina (SNA), North Dakota (SNA), Ohio (SNA), Oklahoma (SNA), Oregon (SNA), Pennsylvania (SNA), Rhode Island (SNA), South Carolina (SNA), South Dakota (SNA), Tennessee (SNA), Texas (SNA), Utah (SNA), Vermont (SNA), Virginia (SNA), Washington (SNA), West Virginia (SNA), Wisconsin (SNA), Wyoming (SNA)
Canada Alberta (SNA), British Columbia (SNA), Manitoba (SNA), New Brunswick (SNA), Nova Scotia (SNA), Ontario (SNA), Prince Edward Island (SNA), Quebec (SNA), Saskatchewan (SNA)

Other Statuses

NatureServe Global Conservation Status Factors

Other NatureServe Conservation Status Information

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
NOTE: The distribution shown may be incomplete, particularly for some rapidly spreading exotic species.

U.S. & Canada State/Province Distribution
United States ALexotic, ARexotic, AZexotic, CAexotic, COexotic, CTexotic, DCexotic, DEexotic, FLexotic, GA, HIexotic, IAexotic, IDexotic, ILexotic, INexotic, KSexotic, KYexotic, LAexotic, MA, MDexotic, MEexotic, MIexotic, MNexotic, MOexotic, MSexotic, MTexotic, NCexotic, NDexotic, NEexotic, NHexotic, NJexotic, NMexotic, NVexotic, NYexotic, OHexotic, OKexotic, ORexotic, PAexotic, RIexotic, SCexotic, SDexotic, TNexotic, TXexotic, UTexotic, VAexotic, VTexotic, WAexotic, WIexotic, WVexotic, WYexotic
Canada ABexotic, BCexotic, MBexotic, NBexotic, NSexotic, ONexotic, PEexotic, QCexotic, SKexotic

Range Map
No map available.

Ecology & Life History Not yet assessed
Economic Attributes
Economically Important Genus: Y
Management Summary Not yet assessed
Population/Occurrence Delineation Not yet assessed
Population/Occurrence Viability
U.S. Invasive Species Impact Rank (I-Rank)
Disclaimer: While I-Rank information is available over NatureServe Explorer, NatureServe is not actively developing or maintaining these data. Species with I-RANKs do not represent a random sample of species exotic in the United States; available assessments may be biased toward those species with higher-than-average impact.

I-Rank: Low/Insignificant
Rounded I-Rank: Low
I-Rank Reasons Summary: Lactuca serriola, a lettuce species native to Europe, is widespread and abundant in the United States, however, from disturbed and waste places. This species has been reported from conservation areas in at least three states, Idaho, Kansas and California and in each site, its abundance and cover was not reported to be great. It is suspected that this species occurs in other conservation areas or native species habitats, but probably not as a dominant species. It has been reported as an aggressive invader in crop lands and orchards, so it is problematic for humans.
Subrank I - Ecological Impact: Insignificant
Subrank II - Current Distribution/Abundance: Medium/Low
Subrank III - Trend in Distribution/Abundance: Medium/Insignificant
Subrank IV - Management Difficulty: Unknown
I-Rank Review Date: 17May2004
Evaluator: Oliver, L.
Native anywhere in the U.S?
Native Range: This lettuce species is native to Europe (Whitson et al. 1996).

Download "An Invasive Species Assessment Protocol: Evaluating Non-Native Plants for their Impact on Biodiversity". (PDF, 1.03MB)
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Screening Questions

S-1. Established outside cultivation as a non-native? YES
Comments: Lactuca serriola is known from every state in the United States including Hawaii. It is absent from only the Virgin Islands and Puerto Rico (Kartesz 1999).

S-2. Present in conservation areas or other native species habitat? Yes
Comments: Lactuca serriola was recorded in trace amounts in the Snake River Plain, southwestern Idaho, where the rare Mulford's milkvetch, Astragalus mulforiae, occurs (Mancuso 2001). It has also been documented in the Konza Praire Biological Station in Kansas (Smith and Knapp 2001) and the Jepson Praire Preserve, Solano California (Pollak and Kan 1998).

Subrank I - Ecological Impact: Insignificant

1. Impact on Ecosystem Processes and System-wide Parameters:Low significance/Insignificant
Comments: No mention of abiotic or system-wide alterations were found, however, this species is reported in rare, native species habitat (Mancuso 2001). This species probably has some affect on the ecosystems where it occurs but it is probably minor as where it has occured in native species habitat it was only been present in trace amounts (Mancuso 2001).

2. Impact on Ecological Community Structure:Low significance
Comments: This Lactuca species is herbaceous (Kartesz 1999) and can affect at least one vegetative layer.

3. Impact on Ecological Community Composition:Insignificant
Comments: This species occurs throughout the United States, however, it appears to be a weed of mostly waste places. It has been recorded in conservation areas, in Idaho's Boise foothills, where it was <1% cover (Mancuso 2001). Lactuca serriola is also considered non-invasive in the Konza Praire Biological Station, Kansas (Smith and Knapp 2001).

4. Impact on Individual Native Plant or Animal Species:Insignificant
Comments: Latuca serriola was found in the same habitat with the rare Astragalus mulfordiae, however, it did not consitute a threat to that species because it was only present in very small amounts (Mancuso 2001).

5. Conservation Significance of the Communities and Native Species Threatened:Insignificant
Comments: Lactuca serriola has been cited in at least three different conservation areas in Idaho (Mancuso 2001), Kansas (Smith and Knapp 2001) and California (Pollak and Kan 1998), but only in small amounts. It probably occurs in other native habitats or conservation ares in the United States in small amounts. This species is usually found in disturbed places and it may be abundant there. Gleason and Cronquist's 1991 flora of the northeast report that it has naturalized throughout most of the United States and that it occurs in waste places and fields. In California, this plant is abundant and occurs in disturbed places (Hickman et al. 1993). In the Great Plains states this species is broadly distributed and occurs in disturbed habitats and waste places (McGregor et al. 1986).

Subrank II. Current Distribution and Abundance: Medium/Low

6. Current Range Size in Nation:High significance
Comments: This species occurs in every state in the contiguous United States. It also occurs in Hawaii, but not in Alaska (Kartesz 1999).

7. Proportion of Current Range Where the Species is Negatively Impacting Biodiversity:Insignificant
Comments: This species does not appear to be a threat to biodiversity. It is more of a problematic species in disturbed places such as crop lands and orchards (Whitson 1996).

8. Proportion of Nation's Biogeographic Units Invaded:High significance
Comments: This species is present in most biogeographic units in the United States (TNC 2001).

9. Diversity of Habitats or Ecological Systems Invaded in Nation:Low significance/Insignificant
Comments: This species occurs is known to invade prairies, but in small amounts (Smith and Knapp 2001, Pollack and Kan 2001). It's possible this species occurs in other native species habitats.

Subrank III. Trend in Distribution and Abundance: Medium/Insignificant

10. Current Trend in Total Range within Nation:Low significance
Comments: This species has spread throughout the United States but doesn't appear to be a major threat to conservation areas as it's cover in those areas is relatively small (Smith and Knapp 2001, Pollak and Kan 1998, Mancuso 2001). Whitson et al. 1996 says that this species is a serious invader of disturbed places though.

11. Proportion of Potential Range Currently Occupied:Insignificant
Comments: This species already occurs throughout the United States (Kartesz 1999).

12. Long-distance Dispersal Potential within Nation:Unknown

13. Local Range Expansion or Change in Abundance:Unknown

14. Inherent Ability to Invade Conservation Areas and Other Native Species Habitats:Low significance/Insignificant
Comments: This species does not seem to invade natural areas frequently even though it is widespread in the United States and is an aggressive invader of disturbed places (Whitson 1996). The reasoning for this is that in the information found indicating that it was found in conservations areas suggests that it abundance and cover was low at those cites, Boise Foothills, Idaho (Mancuso 2001), Konza Prairie Biological Station, Kansas (Smith and Knapp 2001), and Jepson Prairie Preserve, California (Pollak and Kan 1998).

15. Similar Habitats Invaded Elsewhere:Unknown

16. Reproductive Characteristics:Unknown

Subrank IV. General Management Difficulty: Unknown

17. General Management Difficulty:Unknown
Comments: No information was found that indicated that this species is managed.

18. Minimum Time Commitment:Unknown

19. Impacts of Management on Native Species:Unknown

20. Accessibility of Invaded Areas:Unknown

Botanical data developed by NatureServe and its network of natural heritage programs (see Local Programs), The North Carolina Botanical Garden, and other contributors and cooperators (see Sources).

  • Douglas, G.W., G.D. Straley, and D. Meidinger, eds. 1998b. Illustrated Flora of British Columbia, Vol. 1, Gymnosperms and Dicotyledons (Aceraceae through Asteraceae). B.C. Minist. Environ., Lands and Parks, Wildl. Branch, and B.C. Minist. For. Res. Program. 436pp.

  • Gleason, H.A., and A. Cronquist. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. New York Botanical Garden, Bronx, New York. 910 pp.

  • Great Plains Flora Association (R.L. McGregor, coordinator; T.M. Barkley, ed., R.E. Brooks and E.K. Schofield, associate eds.). 1986. Flora of the Great Plains. University Press of Kansas, Lawrence, Kansas. 1392 pp.

  • Herbarium, Department of Botany, University of Manitoba, Winnipeg, Manitoba, Canada.

  • Herbarium, Museum of Man and Nature, 190 Rupert Avenue, Winnipeg, Manitoba.

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  • Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

  • Kartesz, J.T. 1996. Species distribution data at state and province level for vascular plant taxa of the United States, Canada, and Greenland (accepted records), from unpublished data files at the North Carolina Botanical Garden, December, 1996.

  • Kartesz, J.T. 1999. A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. First edition. In: Kartesz, J.T., and C.A. Meacham. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden, Chapel Hill, N.C.

  • Mancuso, M. 2001. Monitoring mulford's milkvetch (Astragalus mulfordiae) in the Boise Foothills: 2000 Results. Idaho Department of Fish and Game. Natural Resource Policy Bureau. Boise, ID. Prepared for Idaho Department of Parks and Recreation through Section 6 funing from U. S. Fish and Wildlife Service, Region 1.

  • Marks, M., and S. Prince. 1981. Influence of germination date on survival and fecundity in wild lettuce Lactuca serriola. OIKOS 36:326-330.

  • Pollak, O., and T. Kan. 1998. The use of prescribed fire to control invasive exotic weeds at Jepson Prairie Preserve. Pages 241-249 in: C. W. Witham, E. T. Bauder, D. Belk, W. R. Ferren Jr., and R. Ornduff (editors). Ecology, Conservation and Management of Vernal Pool Ecosystems - Proceeding from a 1996 Conference. California Native Plant Society, Sacramento, CA. 1998.

  • Scoggan, H.J. 1978. The Flora of Canada. National Museum of Natural Sciences, National Museum of Canada, Publ. in Botany 7(4).

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  • Weber, W. A. and R. C. Wittmann. 1992. Catalog of The Colorado Flora: A Biodiversity Baseline. University Press of Colorado, Niwot, CO.

  • Whitson, T.D. (ed.), L.C. Burrill, S.A. Dewey, D.W. Cudney, B.E. Nelson, R.D. Lee, R. Parker. 1996. Weeds of the West. 5th edition. The Western Society of Weed Science in cooperation with the Western United States Land Grant Universities Cooperative Extension Services, Newark, CA. 630 pp.

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