Thursday, August 19, 2010

LOOK FOR: Joe Pye Weed

We're headed out for a few days of camping and canoeing at Jug Bay this weekend. If the last few years are any guide, the Joe Pye weed will be in full force, and covered in tiger swallowtail butterflies.

butterflies on Joe Pye weed
Photo credit: melystu

There are several different species of Joe Pye, all with large umbels of pinkish-lavender flowers. The individual flowers are small and wispy, but the heads as a whole are huge -- Bill Cullina calls them "as big as basketballs," and it's only sometimes an exaggeration.

tall Joe-Pye Weed, Eupatorium fistulosum
Photo credit: Janet Powell
Adding to the impressive presence, some stalks grow to as high as 14 feet. That's quite a feat after dying back to the ground every winter! The toothed leaves grow in whorls around those tall stems.

Joe Pye weed is named after a healer (aka Jopi) who pushed the plant as a remedy for typhoid in late 18th century New England. Stories conflict on whether he was a Native American or just pretending to be for the sake of selling more medicine. Either way, he has probably gained more fame than he ever dreamed of.

In addition to inducing sweating for fevers like typhoid, Joe Pye weed has a history of use for kidney, gallblader, and urinary ailments. Reportedly, that's how this genus of plants got the name Eupatorium -- after Mithridates Eupator, a ruler in Asia Minor who was the first to use them as medicine in the first century BC.

Butterflies - female Tiger Swallowtail on Joe Pye Weed
Photo credit: Vicki's Nature
Several species of Eupatorium share the big pinkish-purple flower heads and the name Joe Pye weed. You can try to tell them apart like this:
  • Spotted Joe Pye (E. maculatum) has purple mottled stems and a flatter flower cluster;

  • Hollow-stemmed Joe Pye (E. fistulosum) is hollow-stemmed, and very tall;

  • Purple or Sweet-Scented Joe Pye (E. purpureum) has solid stems, and is said to smell like vanilla when crushed;

  • Eastern Joe Pye (E. dubium) has finely spotted stems and the leaves have three strong veins.

In the wild: You'll typically see Joe Pye weed growing in wet areas. It grows in several places along Rock Creek; you'll see more in wetlands like Roosevelt Island, Jug Bay, and Huntley Meadows. Once you find some, stick around and see who stops by. I'm telling you, this stuff is a pollinator magnet.

In your yard: We've got 12-foot-tall E. fistulosum growing in our raingarden. But we've also had good luck with a shorter, shade-tolerant variety in our shady backyard. Just be ready for the height: when I say "shorter," I mean about 5 feet tall! Be sure to inquire about the expected height of the variety you're getting.

joe pye weed
Photo credit: garden beth