Thomas B. Denholm, New Jersey Department of Agriculture, Bugwood.org
Giant Hogweed
Heracleum mantegazzianum

Giant Hogweed (Heracleum mantegazzianum) is an invasive plant. It is a native of Caucasus and was first detected in North America in the early 1900's.

Also known as Cow Parsley, this weed grows to 6 to 16 feet high and has a dark red stem up to 3 inches in diameter. It lives for 5 to 7 years and flowers in its final year, producing umbrella shaped clusters of small white flowers up to 31 inches in diameter. Contact to bare skin can cause photodermatitis, resulting in blisters and scars.

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News

05/21/2013 - Dangerous Giant Hogweed is Dying Off in the Lower Mainland
05/07/2013 - Hogweed Spraying in Huron-Kinloss Starting May
05/02/2013 - City Leading Attack on Invasive Plants
04/22/2013 - King County Sounding the Alarm as Harmful Weeds Begin to Grow
04/09/2013 - SCRD Reviewing Pesticide Policy
03/18/2013 - Ottawa Preparing Plan to Fend Off Alien Plant and Animal Species
03/15/2013 - Invasive Weeds Could Shed Light on Climate-Coping
11/12/2012 - Advise on Invasive Weeds
10/22/2012 - Scottish National Park Tackles Knotweed
09/26/2012 - Invasive Species In Dorset Logged Using Ecology Software
09/19/2012 - New Invasive Species Are Popping Up All Around Wayne County
07/20/2012 - Hogweed infestation grows on Albion Road in Windham
07/11/2012 - Cornell University Releases List of Plants You Do Not Want to ...
07/11/2012 - Giant Hogweed Found in Bangor
06/29/2012 - Effort to Control Giant Hogweed in St. Lawrence County Under Way
06/15/2012 - Giant Hogweed Causing Confusion
06/15/2012 - Invasive Plant can Burn Scar and Blind People
06/07/2012 - Stay Far Away From These Plants
06/06/2012 - Giant Hogweed Can be Dangerous,
05/24/2012 - Dangerous Plant Taking Root in Maine
05/21/2012 - Project to Stop Invasive Plants
04/12/2012 - Big Bad Weed Growing Fast
04/06/2012 - Oswego County Earth Week Set April 21 – 29
03/23/2012 - Woodlot owners learn how to take the fight to invasive plant s...
02/27/2012 - North American Invasive Plant Ecology and Management Short Course
02/27/2012 - Wildland Weed Field Courses-Invasive species
02/13/2012 - How to Catch a Killer Weed
08/23/2011 - Invasive Hogweed Found in Woodstock
08/10/2011 - State Warning Property Owners to be on the Lookout for Noxious...
08/05/2011 - Be on Guard Against the Hogweed Menace
08/05/2011 - Giant Hogweed New Confirmed in Areas Around the State of Maine
08/01/2011 - Beware Of The Giant Hogweed
08/01/2011 - State Confirms Poisonous Plant Sightings
07/28/2011 - Report Sightings of Noxious Invasive Giant hogweed
07/20/2011 - Imposters Mirror Giant Hogweed
07/08/2011 - Giant Hogweed 8 Facts You Must Know About the Toxic Plant
06/20/2011 - Stop Alien Invaders from Taking Over the Environment
06/07/2011 - Statewide Giant Hogweed Eradication Program to Continue this S...
05/19/2011 - CH Says Time is Ripe to Destroy Giant Hogweed
05/10/2011 - King County Offers Free Workshops to Help Residents Tackle Tou...
05/09/2011 - Giant Hogweed is a Dangerous Invader
05/05/2011 - Remove These NonNative Plants For Your Garden and the Environment
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