Alberta Native Plant Council

Feature Plant

Cow Parsnip
(Heracleum lanatum Michx.)

Cow Parsnip (Heracleum lanatum)
Photo by Christine Messom

Cow parsnip occurs throughout Alberta in moist, often shady, locations. Other plants with compound umbels of white flowers are sometimes mistaken for it because the form is so familiar that the details escape notice. With new weed regulations in Alberta this summer, and publicity on national television, many people have reacted "OMG, is that Giant Hogweed"? Well, no, it's not, but they are very similar. Giant Hogweed is bigger, and more obnoxious.

Cow parsnip is native to North America. Grizzly Bears eat it, presumably because it is nutritious rather than tasty. Steve Herrero, who tried eating all the plants that bears eat during his studies of their diet, said it tasted terrible, with an aftertaste that lasted for days. Like Giant Hogweed, it contains irritating chemicals to discourage herbivores.

Furocoumarins, the family of chemicals responsible, are found in varying degrees (and with differing chemical structures) in all species of Heracleum, and also in other members of the family, Apiaceae, including Angelica and parsnips. Fortunately, no Giant Hogweed has as yet been found and confirmed in Alberta.

See Heracleum mantegazzianum in the Online Wiki for more information about the differences.

Cow Parsnip (Heracleum lanatum)
Photo by Lorna Allen