Cow Parsnip - Heracleum

We hiked up the Wolverine Peak trail today. It was clearly Cow Parsnip Day. Everywhere we were surrounded by the large white flowers of the cow parsnip plant. The pictures below were all taken today in Anchorage. You can click on any of them to enlarge it. The information on Cow Parsnips come from the links.

Cow Parsnip
Heracleum maximum (Heracleum lanatum)
• Family: Carrot (Apiaceae)
• Habitat: moist meadows, thickets, streambanks
• Height: 4-9 feet
• Flower size: 1/4 to 1/2 inch across, in clusters 4-8 inches across
• Flower color: white
• Flowering time: June to August
• Origin: native

From Connecticut Botanical Society

Cow parsnip Heracleum lanatum has been used medicinally. The root for toothaches (placed directly to the area) or you can also use a tincture of the root or seeds, it is less irritating to the gums than cloves. The root and seeds are used as an antispasmodic to the intestinal tract. If used in a tea, make sure it is dried first, the tea is used for nausea of a persistent nature, when you have not yet vomited, as well as acid indigestion and heart burn according to Micheal Moore in Medicinal Plants of the Mountain West. The seeds tinctured are effective for stomach aches, the dose should be one or two drops. Do not use this plant during pregnancy or nursing.

From The Herbalist's Path Blog

Cow parsnip is a valuable forage species for livestock, deer, elk, moose, and bear. Moose in Montana and Yellowstone National Park eat cow parsnip. In low elevation riparian areas it is an important food for grizzly bear, especially in the spring. In Glacier National Park, cow parsnip comprised 15 percent of grizzly bear total diet volume, spring through fall, in 1967-1971 and 1982-1985.

From Little Flower's Medicine of North American Plants

This is the largest species of the carrot family in North America. The genus is named for Hercules, who is reputed to have used these plants for medicine. Early in each year, Native Americans peeled and ate the young sweet, aromatic leaf and flower stalks.

From eNature.com

This very tall plant has huge leaves and flat umbels of numerous tiny white flowers; stem is grooved, woolly, hollow, and stout.
Flowers: umbel to 12" (30 cm) wide, often in groups; each flower with 5 petals, those at margin of umbel larger, about 1/4" (6 mm) long, cleft in middle, often tinged with purple.

From eNature











People new to Alaska often confuse Cow Parsnip (left below) with Devil's Club (right below.) You can see from these two pictures, both have large leaves that initially seem similar.










The Devil's Club leaves have hooked thorns underneath.







































"The green stems of pushki [cow parsnip] are covered with fine hairs, which give them a slightly fuzzy or furry texture." From Kenai National Wildlife Refuge, Refuge Notebook.

The [Devil's Club] plant grows 5 to 8 feet (1.5 to 2.4 meters) tall and is covered with thorns up to an inch (2.5 centimeters) long."Even the leaves have little-bitty thorns," said Peggy Hunt, an agronomist at the Native Plant Nursery in Palmer, Alaska. "They go through your skin. You wear jeans, they still go through those jeans. And the thorns will fester. It's like getting a splinter. You really have to dig them out."

From National Geographic The National Geographic article goes on to talk about the medicinal aspects of Devil's Club.



For some people Cow Parsnip poses a danger of severe skin problems.

Known Hazards Many members of this genus, including this species[65], contain furanocoumarins. These have carcinogenic, mutagenic and phototoxic properties. The fresh foliage can cause dermatitis[21]. If the juice and hairs of the outer skin are left on the face and mouth, they can cause blisters[212]. This effect is especially prevalent for people with fair complexions[256].

From Plants for a Future

It is interesting to ask if this phototoxicity has any adaptive value for the members of the carrot family? Is this toxicity, for example, a chemical defense against some kind of plant-eating animal (herbivore)? First, we should note that bears and moose eat young pushki plants, apparently without suffering any kind of sunburn effects. Indeed, in the Lower-48 pushki is considered a valuable forage species for deer, elk, moose, and livestock. A study in Glacier National Park found that pushki comprised 15% of grizzly bear diet, spring through fall. All this suggests that mammals, other than humans, are not bothered by any phototoxicity effects of pushki.

Nevertheless, you don't see many insects eating pushki. A fascinating study of a close cousin, wild parsnip (Pastinaca sativa), found that the furanocoumarins were potent deterrents for most insects, but one insect has evolved the ability to break down the furanocoumarins and eat wild parsnip. This insect - a caterpillar called the "parsnip webworm" (Depressaria pastinacella) - also eats pushki. If we ever need a biocontrol agent for pushki, parsnip webworm would be a good place to start.

From Kenai National Wildlife Refuge, Refuge Notebook.


[Update  June 2010:  Here's a link to a the Juneau-Douglas Science fair and a video of David Mendivil who explains his project "How the Concentration of Light Activated Furanocoumarins Found in Cow Parsnip Affects the Mortality Rate of Mosquito Larvae."]