Euphorbia esula

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Euphorbia esula
Euphorbia esula - kibe piimalill.jpg
Scientific classification e
Kingdom: Plantae
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Malpighiales
Family: Euphorbiaceae
Tribe: Euphorbieae
Subtribe: Euphorbiinae
Genus: Euphorbia
Species: E. esula
Binomial name
Euphorbia esula

Euphorbia esula, commonly known as green spurge or leafy spurge,[1] is a species of spurge native to central and southern Europe (north to England, the Netherlands, and Germany), and eastward through most of Asia north of the Himalaya to Korea and eastern Siberia.[2][3][4]

Detail of flowers and immature seeds

It is a herbaceous perennial plant growing to 1-1.2 m tall, with several stems branched from the base. The stems are smooth, hairless or slightly hairy. The leaves are small, lanceolate, 4-8.5 cm long and up to 1 cm broad, with a slightly wavy margin. The flowers are small, produced in umbels with a basal pair of bright yellow-green petal-like bracts. Clusters of the bracts appear in late spring, while the actual flowers do not develop until early summer. All parts of the plant contain a toxic white milky sap.[4][5]

It reproduces readily like by seeds that have a high germination rate and may remain viable in the soil for at least eight years.[6] The seed capsules open explosively, dispersing seed up to 5 m from the parent plant, and may be carried further by water and wildlife. Leafy Spurge also spreads vegetatively from the root system, which is complex, reported to reach 8 m into the ground and 5 m across, and may have numerous buds.[7][8]

There are two subspecies and a hybrid subspecies:[2][4]

  • Euphorbia esula subsp. esula. Leaves broadest near apex; umbel bracts 5–15 mm. Throughout the range of the species.
  • Euphorbia esula subsp. tommasiniana (Bertol.) Kuzmanov (syn. E. waldsteinii (Sojak) A.R.Smith; E. virgata Waldst. & Kit.). Leaves broadest at the middle; umbel bracts 12–35 mm. Eastern Europe, western Asia.
  • Euphorbia esula nothosubsp. pseudovirgata (Schur) Govaerts. Hybrid between the above two subspecies.

As an invasive plant[edit]

Leafy spurge was transported to the United States possibly as a seed impurity in the early 19th century. First recorded from Massachusetts in 1827, leafy spurge spread quickly and reached North Dakota within about 80 years.[9] [10]It now occurs across much of the northern U.S., with the most extensive infestations reported for Montana, North Dakota, Nebraska, South Dakota, and Wyoming. Since the introduction of leafy spurge to the United States, it has been found in 458 counties in 26 states.[11] It has been identified as a serious weed on a number of national parks and on reserves of The Nature Conservancy in eleven northern states. It is now classified as an invasive species by the United States Department of Agriculture.[7][12] It was first recorded in Alberta, Canada in 1933 and is also naturalised in parts of South America.[2][13]

Leafy spurge grows in a variety of different climate environments.[14] It displaces native vegetation in prairie habitats and fields through shading and by usurping available water and nutrients and through plant toxins that prevent the growth of other plants underneath it. It is an aggressive invader and, once present, can completely overtake large areas of open land. Leafy spurge quickly colonizes in areas with bare soil, especially those caused by human disturbance where native species are removed. One method of control suggested is to limit the amount of bare soil from these disturbances.[15] It is toxic as well.[7]

Leafy spurge quarantine sign at the Idaho state line

Because of its persistent nature and ability to regenerate from small pieces of root, leafy spurge is extremely difficult to eradicate. In Saskatchewan Canada, leafy spurge spread on trails used by settlers and traders. Modernly the travel of leafy spurge has been linked to railroads and the use and transport of infested hay used for agriculture.[11] Biological control offers a highly promising management tactic for leafy spurge. Goats, apparently able to graze on the plant without ill effect, have been used on rail trails in Idaho to clear leafy spurge from the trail shoulders.[16] Sheep have been used in North Dakota, along with herbicides and flea beetles, to fight it.[17] The U.S. Department of Agriculture has shown success using six European insects that feed on leafy spurge. These include a stem and root-boring beetle (Oberea erythrocephala), five root-mining flea beetles (Aphthona spp.),[13] The Spurge Hawk-moth (Hyles euphorbiae),[18] and a shoot-tip gall midge (Spurgia esulae). Large scale field-rearing and release programs are carried out cooperatively by federal and state officials in many northern states. The results are not as immediate as when herbicides are used but, if pesticide use is kept to a minimum, large numbers of these insects build up within a few years and have shown impressive results.[7]

Several systemic herbicides have been found to be effective if applied in June, when the flowers and seeds are developing, or in early-to-mid-September, when the plants are moving nutrients downward into the roots. Preliminary research suggests that chemical treatment in the fall followed by a spring burn to reduce seed germination may be an effective strategy for reducing leafy spurge infestations. Multiple treatments are necessary every year for several years, making leafy spurge control an extremely expensive undertaking.[19] If left uncontrolled for a single year, leafy spurge can reinfest rapidly. Prescribed burning, in conjunction with herbicides, may also be effective.[7]

As a model weed[edit]

Leafy spurge is being developed as a model to answer fundamental questions of weed biology. Over 55,000 ESTs have been sequenced from all plant tissues including tissues from plants that were cold stressed, drought stressed, or attacked by both flea beetles and gall midges. Analysis of the EST sequences indicated that 23,000 unique sequences representing more than 19,000 unigenes were obtained. These sequences are now available on Genbank. The unigenes have been used to develop cDNA microarrays that also include more than 4,000 additional cDNAs from cassava (another Euphorb related to leafy spurge). These microarrays are being used to identify physiological processes and signals that regulate bud dormancy (one of the main reasons leafy spurge is difficult to control)[20] and invasiveness.


  1. ^ "BSBI List 2007". Botanical Society of Britain and Ireland. Archived from the original (xls) on 2015-01-25. Retrieved 2014-10-17. 
  2. ^ a b c "Euphorbia esula". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 2017-12-18. 
  3. ^ Flora Europaea: Euphorbia esula
  4. ^ a b c Blamey, M. & Grey-Wilson, C. (1989). Flora of Britain and Northern Europe. ISBN 0-340-40170-2
  5. ^ Huxley, A, ed. (1992). New RHS Dictionary of Gardening. ISBN 0-333-47494-5
  6. ^ Lym, Rodney G. (1998). "The Biology and Integrated Management of Leafy Spurge (Euphorbia esula) on North Dakota Rangeland". Weed Technology. 12 (2): 367–373. doi:10.2307/3988402. 
  7. ^ a b c d e U.S. National Park Service description
  8. ^ Selleck, G. W.; Coupland, R. T.; Frankton, C. (1962-02-01). "Leafy Spurge in Saskatchewan". Ecological Monographs. 32 (1): 1–29. doi:10.2307/1942359. ISSN 1557-7015. 
  9. ^ Britton, N. L. 1921. The leafy spurge becoming a pest. J. New York Bot. Garden. 22:73-75.
  10. ^ Dunn, P.H. (1985). "Origins of leafy spurge in North America" (PDF). Weed Science Society of America. Retrieved October 25, 2017. 
  11. ^ a b Dunn, P. H. (1979/09). "The Distribution of Leafy Spurge (Euphorbia esula) and Other Weedy Euphorbia spp. in the United States". Weed Science. 27 (5): 509–516. doi:10.1017/S0043174500044507. ISSN 0043-1745.  Check date values in: |date= (help)
  12. ^ Species Profile - Leafy Spurge (Euphorbia esula), National Invasive Species Information Center, National Agricultural Library
  13. ^ a b Andrea Ruth Kalischuk (May 2001). "Density and efficacy of the flea beetle Aphthona lacertosa (Rosenhauer), an introduced biocontrol agent for leafy spurge, in Alberta" (PDF). University of Lethbridge. 
  14. ^ "Pest Management- Invasive Plant Control Leafy spurge (Euphorbia esula)" (PDF). National Resources Conservation Service. January 2007. Retrieved 23 October 2017. 
  15. ^ Belcher, Joyce W.; Wilson, Scott D. (1989). "Leafy Spurge and the Species Composition of a Mixed-Grass Prairie". Journal of Range Management. 42 (2): 172–175. doi:10.2307/3899318. 
  16. ^ "War on Weeds," Rails to Trails Magazine, Spring 2004, p. 3
  17. ^ McGrath, Susan, 2005m "attack of the aline invaders," National Geographic 2005, pp. 92-117, p. 114
  18. ^ Coombs, E. M., et al., Eds. (2004). Biological Control of Invasive Plants in the United States. Corvallis: Oregon State University Press, 254.
  19. ^ Davis, David G; Swanson, Harley R (2001-10-01). "Activity of stress-related enzymes in the perennial weed leafy spurge (Euphorbia esula L.)". Environmental and Experimental Botany. 46 (2): 95–108. doi:10.1016/S0098-8472(01)00081-8. 
  20. ^

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