Family: Apiaceae, Carrot view all from this family
Description Introduced; noxious weed. A tree-size herbaceous plant with giant white, umbrella-shaped flower clusters; very large, lobed leaves; and hollow, hairy stems up to 4" (10 cm) in diameter.
Flowers: umbels to 30" (75 cm) wide.
Leaves: deeply divided, to 5' (1.5 m) long.
Height: 8-14' (2.4-4.2 m).
Warning Handling leaves and other plant parts can cause blisters, rash, long-term skin discoloration, and exaggerated sun-sensitivity. Children have reportedly been contaminated with the sap when employing the hollow stems as pea shooters.
Habitat Moist, rich sites; roadsides, stream banks, disturbed areas.
Range Native to the Caucasus region of Asia; introduced in the United States and escaped from cultivation in Maine, New York, Pennsylvania, Michigan, and Washington state.
Discussion This introduced member of the carrot family looks like an outsized version of another non-native carrot, Queen Anne's Lace. Dried stems and flower skeletons persist in winter. Giant Hogweed is considered a noxious pest in a number of states; it escapes from cultivation into natural habitats and it causes unpleasant reactions if handled.