Management Information
Physical: Hand-pulling and cutting have been found to be ineffective and could actually increase the spread.Chemical: Chemical control is not completely effective because the root system blocks the downward movement of the herbicides. The extent of most invasions is so wide that spraying is impractical and too costly. Also, most herbicides for E. esula are detrimental to desirable broadleaved range plants. Herbicides and prescribed burning can be effective if repeated and done at the appropriate time. Biological: Biological control seems to be the most viable control measure. Species under consideration are the cerambyciid long-horned beetle, chrysomelid flea beetles, and the cecidomyiid midge. Sheep and goats, which feed heavily on this plant, have also been shown to be effective in controlling this plant's spread. Integrated pest management: Studies have shown than integrated approach to leafy spurge control is more effective than following a single option. The Ecological Areawide Management (TEAM) of the Leafy Spurge programme found that an IPM (integrated pest management approach), with an integration of multiple tools (herbicides, flea beetles, sheep and burning) proved to be effective in leafy spurge control programmes (Anderson et al., 2003).Aphthona spp. flea beetles on both the leafy spurge control and the biological control agent populations it was found that Leafy spurge density was reduced more rapidly when A. nigriscutis or a mixture of A. czwalinae and A. lacertosa was combined with a fall-applied treatment of picloram plus 2,4-D than when either method was used alone. The combination treatment reduced leafy spurge density 3 to 5 yr earlier than did either the herbicides or the biocontrol agents alone and once reduced, the Aphthona flea beetles maintained acceptable control for at least 7 yr. Spring-applied herbicides eliminated the adult food source and negatively affected the flea beetle establishment, but fall-applied treatments did not reduce the flea beetle establishment or its reproduction. The combination treatment was most successful when used with established Aphthona spp. populations that were not increasing in size or reducing leafy spurge density. Land managers could realize a three- to five fold cost savings with the combination treatment compared with herbicides alone (Lym et al., 2002).
In studies using microcosms in a greenhouse consisting of potted, caged plants of E. esula / E.virgata, combinations of Fusarium oxysporum, Rhizoctonia solani, or both fungi with adults and larvae of the flea beetle Aphthona spp. caused significantly greater rates of injury to E. esula / E.virgata than any single agent. The results support the idea that supplementing flea beetle establishments with plant pathogens can be an effective means of both causing higher rates of successfully impacted release sites and greater biocontrol impact at individual release sites (Caesar, A. J. 2003).
Location Specific Management InformationArizona (United States (USA))
Prohibited Noxious Weed Big Horn (United States (USA))
Considered Noxious Weed.
Information from Fremont County Wyoming states that Aphthona flea beetles used in the bio-control of leafy spurge have reduced it to less than 5% ground cover in many areas ( Baker, J. pers.comm., May 2004.). California (United States (USA))
E.esula has been listed as a Noxious Weed. A study during the period 1972-2000, by the California Department of Food and Agriculture on eradication targeted 18 species and 53 separate infestations. The results demonstarted that professional eradication of exotic weed infestations smaller than one hectare is usually possible. In addition, about 1/3 of infestations between 1 ha and 100 ha and 1/4 of infestations between 101 and 1000 ha were eradicated. Out of the two infestations of leafy spurge, one was eradicated and the eradication process was ongoing in case of the other. The results also indicated that costs of radication projects increased dramatically. It was concluded that: the cost of eradicating infestations larger than 1000 ha was very high; that early detection of the presence of an invasive taxon can make the difference
between being able to employ offensive strategies (eradication), and the necessity of retreating to a defensive strategy that usually means an infinite financial commitment; and, that if an exotic weed is already widespread, species-specific biological control may be
the only long-term effective method able to suppress its abundance over large areas (Rejmanek and Pitcairn, 2002). Colorado (United States (USA))
Considered Noxious Weed Hawaii (United States (USA))
Considered Noxious Weed Iowa (United States (USA))
Primary Noxious Weed Kansas (United States (USA))
Considered Noxious Weed Klickitat (United States (USA))
Class B Noxious Weed Kootenai (United States (USA))
Considered Noxious Weed Minnesota (United States (USA))
Primary Noxious Weed Missoula (United States (USA))
Category 1 Noxious Weed Nebraska (United States (USA))
Considered Noxious Weed Nevada (United States (USA))
Considered Noxious Weed New Mexico (United States (USA))
Class A Noxious Weed South Dakota (United States (USA))
Considered Noxious Weed, regulated non-native plant species Utah (United States (USA))
Considered Noxious Weed Wisconsin (United States (USA))
Considered Noxious Weed
Management Resources/Links
1. Anderson et al., 2003. The Ecological Areawide Management (TEAM) of leafy spurge program of the United States Department of Agriculture–Agricultural Research Service . Pest Management Science 59: 609–613.
Summary: A report on an integrated approach to Leafy spurge control. Abstract 2. Caesar, A. J. 2003. Synergistic interaction of soilborne plant pathogens and root-attacking insects in classical biological control of an exotic rangeland weed. Biological Control. 28(1). 144-153.
Summary: Supplementing flea beetle establishments with plant pathogens, for increased effectiveness in biological control of Leafy spurge. Abstract 5. Leafy Spurge, Gwendolyn Thunhorst, 1999. The Nature Conservancy, Arlington, VA. and Jil M. Swearingen, U.S. National Park Service, Washington, DC.
Summary: Report on description, biology, effects of introduction, distribution, and management. 9. Scheiman, Daniel M.et al., 2003. Effects of leafy spurge infestation on grassland birds. Journal of Wildlife Management. 67(1). 115-121.
Summary: Impacts of spurge on grassland bird densities. Abstract Results Page: 1
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