Text Size:   A+ A- A   •   Text Only
Find     
Oregon Invasive Species Council

June 2009- Giant Hogweed
Invasive Species of the Month
June 2009 Invasive Species of the Month
Giant Hogweed (Heracleum mantegazzianum)

click calendar below for larger image
 


What is Giant Hogweed?
Photo by Tom Forney, ODA
Native to Asia, Giant hogweed is a member of the carrot or parsley family, and its most impressive characteristic is its massive size. It grows 10 to 15 feet tall. Because of its invasive nature, it soon becomes a pest within the garden and readily escapes. It has naturalized in many of the places where it was introduced. This plant is a public health hazard. Do not expose bare human skin to the plant or breathe the smoke from fires if it is being burned. The plant exudes a clear watery sap that sensitizes the skin to ultraviolet radiation. Humans often develop severe burns to the affected areas resulting in blistering and painful dermatitis. Blisters can later develop into purplish or blackened scars.
June 2009 calendar events
June 2009 Oregon Invasive Species Council
calendar events

click calendar below for larger image
 


Where?
Currently, giant hogweed is foundin the northwestern part of Oregon (west of the Cascades). There are isolated populations of Giant hogweed in many states, but most are being eradicated.  In Oregon, about 100 Giant hogweed sited have been identified, and they are being treated.
Lookalike?
Yes, cow parsnip is a close cousin.  Giant hogweed is larger, and the base of the stems are purple and bumpy.  Cow parsnip stems are green and don't have bumps.
What can you do?
If you suspect you have been attacked by an Africianized honeybee, report it immediately at 1-866-INVADER or www.oregoninvasiveshotline.org

Pest Risk Assessment
Pest Risk Assessment of the Giant Hogweed
All months of 2009 calendar
All months of the 2009 Oregon Insavive Species Calendar