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Home > Horticulture > Giant Hogweed
Giant Hogweed

Giant Hogweed, Heracleum mantegazzianum

 

History

Giant hogweed was introduced into Europe and North America from Asia in the early 1900's. It's impressive growth made it a desirable garden plant. However, giant hogweed soon escaped cultivation and established itself in natural areas in several states including Maine. Distribution of giant hogweed in Maine

 

A Hazardous Plant

Along with its impressive growth habit, giant hogweed is noteworthy because its sap causes severe skin irritation. When susceptible people come in contact with the sap and the skin is exposed to sunlight, painful blisters develop. 

If you must handle this plant be careful not to come into contact with sap from broken stems. You should be well covered, wearing gloves, long sleeves and long pants.

 

Identification

When identifying giant hogweed, look for the following characteristics:

  • Very tall plants, 8-14 feet in height
  • Hollow stems that are 2-4 inches in diameter with rigid hairs and purple blotches
  • Leaves that are unevenly lobed and up to 5 feet long
  • Flower clusters up to 2 feet across occurring from mid June to late July
  • Dead stems that remain upright throughout the winter

Several plants including cow parsnip, angelica and poison hemlock, look similar to giant hogweed. Pictures of giant hogweed and look-a-likes

 

 

More Information on Giant Hogweed

Giant Hogweed: an attractive, but dangerous noxious weed [PDF]

Giant Hogweed Control for Homeowners [PDF]

Giant Hogweed Best Management Practices Manual [PDF]

 

 

 

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