Do Not Touch This Plant!
Giant hogweed (Heracleum mantegazzianum) is a VERY LARGE, invasive plant that can cause painful burns and permanent scarring. Brushing against or breaking the plant releases sap that, combined with sunlight and moisture, can cause a severe burn within 24 to 48 hours. Giant hogweed is a Federally listed noxious weed and NYS law prohibits its possession with the intent to sell, import, purchase, transport, introduce or propagate.
What to do if You Come in Contact With Giant Hogweed
- Wash the affected area thoroughly with soap and COLD water as soon as possible
- Keep exposed area covered or away from sunlight for 48 hours
- If a reaction occurs, topical steroids applied early can reduce the severity of the reaction and ease discomfort
- If a reaction has occurred, the area of skin may be sensitive to sunlight for a few years and you may want to apply sun block or keep the affected area covered from the sun when possible
- See a physician if you have a reaction or any questions
- If sap goes in eyes, rinse them with water, wear sunglasses or cover your eyes, and seek emergency medical care IMMEDIATELY to prevent potential blindness
Description
Giant hogweed is a biennial or perennial herb in the carrot family (Apiaceae) which can grow to 14 feet or more. Its hollow, ridged stems grow 2-4 inches in diameter and have dark reddish-purple blotches. Its large compound leaves can grow up to 5 feet wide. Its white flower heads can grow up to 2 1/2 feet in diameter. Some other plants look very similar.
Lookalikes
Plant | Flower | Leaf | Stem |
---|---|---|---|
Giant Hogweed 7-14 feet tall | White umbrella-shaped flower clusters | Compound, lobed, deeply incised, | Green with purple splotches and coarse |
Cow Parsnip 5 to 8 feet tall | White flat-topped flower clusters no longer | Compound, less incised than hogweed, | Green and rigid with fine white hairs |
Angelica 4 to 9 feet tall | Softball-sized and shaped clusters, | Compound leaves that may extend | Smooth, waxy purple, 1 to 2.5 inches |
Up to 5 feet tall | Single flower stalk with flat-topped | Compound, pinnate, 5 to 15 toothed | Yellowish-green with full length |
Queen Anne's Lace 1 to 3 feet tall | Flat-topped umbel of white flower clusters, | Compound, pinnate, fern-like. | Green, covered with bristly hairs. |
Poison Hemlock 4 to 9 feet tall | Small and white arranged in numerous | Bright green, small and fern-like, | Smooth and waxy stem with purple |
Common Elderberry Shrubs 5 to 12 feet tall | White flat-topped or slightly rounded flower | Compound, pinnate, 5 to 11 toothed leaflets | Older woody stems or young green stems |
Pokeweed Up to 10 feet tall | Greenish-white racemes (linear flower | Alternate, large, entire leaves (not leaflets) | Green to red or purplish, smooth |
Distribution and Habitat
Giant hogweed is a native of the Caucasus Mountain region between the Black and Caspian Seas. It was introduced to the United States in the early twentieth century as an ornamental garden plant. It has become established in New England, the Mid-Atlantic Region, and the Northwest. Giant hogweed grows along streams and rivers, as well as in fields, forests, yards, and near roadsides. It grows in sunny areas and in partial shade, preferring moist soils.
Management
From late April through August, DEC field crews visit each confirmed giant hogweed site, and use the appropriate control method. This is free of charge to the landowner. In general management is decided by the size and number of plants:
- root-cutting is used at smaller sites with less than 400 plants,
- herbicide is used at larger sites with greater than 400 plants; and
- flower/seed head removal is used at all sites to limit seed dispersal.
Sites are visited each year until the plants are eradicated. When no more plants are found the site will be monitored for three subsequent years.
For a site to be visited and controlled, landowners must give annual permission. For crews to use herbicide control, landowners must first sign a property permission form.
Past years' annual reports:
What You Can Do To Help
Report Giant Hogweed
If you see giant hogweed, take a picture and email DEC or call the Giant Hogweed Information Line: 845-256-3111. Provide photos, detailed directions to the plant infestation (GPS coordinates and street address preferred) and estimate the number of plants.
DEC has giant hogweed publications for distribution. Email DEC or call the Giant Hogweed Information Line at 845-256-3111 to let us know how many brochures and posters you can use. Provide your mailing address so we can mail them to you.