MN NWAC Risk Common Name Latin Name Assessment Worksheet (04-2011) Giant Hogweed Heracleum mantegazzianum Sommier &Levier Reviewer Affiliation/Organization Date (mm/dd/yyyy) Anthony Cortilet MN Dept. of Agriculture 05/25/2011
Box Question Answer Outcome 1 Is the plant species or genotype non-native? Yes – GH is native to the Caucasus Region of Asia. Box 3 3 Is the plant species, or a related species, Yes – Found in Pennsylvania, Maryland, Connecticut, Box 6 documented as being a problem elsewhere? District of Columbia, Maine, Massachusetts, Michigan, New York, Ohio, Oregon, Washington, and Wisconsin. - Federally listed noxious weed and regulated in 13 U.S. states 6 Does the plant species have the capacity to Yes – is hardy to zones 2, 3 & 4. – Established in WI, establish and survive in Minnesota? MI, NY, and OR. A. Is the plant, or a close relative, currently Yes – Cow Parsnip - Heracleum maximum, which is a Box 7 established in Minnesota? native species. B. Has the plant become established in areas Yes – WI, MI, NY, and parts of OR. Box 7 having a climate and growing conditions similar to those found in Minnesota? 7 Does the plant species have the potential to Yes – Assumption based on hardiness in other states reproduce and spread in Minnesota? where established. A. Does the plant reproduce by No Question 7C asexual/vegetative means? B. Are the asexual propagules effectively dispersed to new areas? C. Does the plant produce large amounts of Yes – seeds are cold hardy and break dormancy through Question 7F viable, cold-hardy seeds? winter cold and spring moisture. – Ohio State Bulletin lists seed numbers/plant @ 20,000 F. Are sexual propagules – viable seeds – Yes – primarily by humans and water, some wind Question 7I effectively dispersed to new areas? dispersal. I. Do natural controls exist, species native to Not known for other infested U.S. States and Canada, Box 8 Minnesota, that are documented to effectively none known for MN. prevent the spread of the plant in question? Box Question Answer Outcome 8 Does the plant species pose significant Yes – poses significant threat to human and light- human or livestock concerns or has the skinned livestock health, native ecosystems, managed potential to significantly harm agricultural landscapes, and pasture/rangeland operations. production, native ecosystems, or managed landscapes? A. Does the plant have toxic qualities, or Yes – causes severe phytophotodermatitis to humans Box 9 other detrimental qualities, that pose a and light-skinned livestock through high concentrations significant risk to livestock, wildlife, or of chemical furocoumarins present in the sap. Contact people? with the eyes can cause temporary and sometimes permanent blindness. – May cause ulcers or oral lesions when eaten by some grazing animals. 9 Does the plant species have clearly defined No benefits that outweigh associated negative impacts? A. Is the plant currently being used or No – not as a nursery species. Some mention in the Box 10 produced and/or sold in Minnesota or native literature of seeds (mashed) sold as a spice for Middle to Minnesota? Eastern cooking in some parts of the U.S. – Dried umbels have been used in floral arrangements. 10 Should the plant species be enforced as a Yes noxious weed to prevent introduction &/or dispersal; designate as prohibited or restricted? A. Is the plant currently established in Not known at this time. Established in WI and MI. List the plant as a Minnesota? Prohibited – Eradicate Noxious Weed Final Results of Risk Assessment Review Entity Comments Outcome NWAC Listing Subcommittee Based on the severity to human health, the close List as a Prohibited proximity of infestations in MI and WI, the federal Noxious Weed on the noxious weed designation, and the lack of documented Eradicate List. infestations in MN to date; this species should be listed as a Prohibited Noxious Weed on the Eradicate List. NWAC Full-group List as a Prohibited – Eradicate Species Box Question Answer Outcome MDA Commissioner Approved as a Prohibited Eradicate Species Listed as a Prohibited – Eradicate Species File Number: MDARA00012GIAHW_11_30_2011
References: A.H. Andrews, C.J. Giles, and L.R. Thomsett. 1985. Short Communication. Suspected Poisoning of a goat by giant hogweed. Veterinary Record. 116: 205-207. Oregon Department of Agriculture. Plant Risk Assessment for Giant Hogweed, Heracleum mantegazzianum. 2009. 11 pages. http://www.oregon.gov/OISC/calendar_june09_assessment.shtml
USDA Plant Database Profile for Giant Hogweed, Heracleum mantegazzianum: http://plants.usda.gov/java/profile?symbol=HEMA17
EDDMaps reports for Heracleum mantegazzianum: http://www.eddmaps.org/distribution/usstate.cfm?sub=4536
Michigan Department of Agriculture, USDA –APHIS. Brochure: Giant Hogweed, Heracleum mantegazzianum, an attractive but dangerous noxious weed: http://mipn.org/MDA_Hogweed_Brochure.pdf
USDA-APHIS. Factsheet. Giant Hogweed: http://www.aphis.usda.gov/publications/plant_health/content/printable_version/fs_phhgweed.pdf
New York State Department of Environmental Conservation. Web Site. Giant Hogweed: http://www.dec.ny.gov/animals/39809.html
The Ohio State University extension Fact Sheet. Giant Hogweed, Heracleum mantegazzianum: http://ohioline.osu.edu/anr- fact/hogweed.html