Good year for wild quinine

Wild quinine (Parthenium integrifolium; sometimes called "American feverfew") is having a banner year at Pleasant Valley Conservancy. This plant, listed by the USDA as Endangered in Minnesota and Maryland, Threatened in Wisconsin, and Extirpated in Pennsylvania, is surprisingly easy to grow. Presumably it has become rare because its principal habitat, rich mesic prairie, is now dominated by agricultural row crops.

Wild quinine flower head

At Pleasant Valley Conservancy it has been in the seed mix for some of our planted prairies, as well as in open savannas. Typical of most plantings, the success varied with the year of planting and the details of the seed mix. Our best success has been in the Ridge Prairie, a 1.5 acre site at the far east end of the Conservancy. It is interesting that this prairie is on sandy soil at the top of a ridge, where mesic conditions would not be expected. Despite this, wild quinine has been present extensively since the early years of planting.

This year it is especially prolific, presumably because of the good consistent precipitation we have been having.

Ridge Prairie, looking North. Most of the white flower heads are wild quinine

Map of the distribution of wild quinine in the U.S.
Courtesy of the Biota of North America Program, Chapel Hill, N.C.
Yellow areas: species present but rare

 Despite the common name, this species does not contain quinine. Rather, the leaves have a bitter taste resembling that drug. It is fortunate that wild quinine is easy to grow in gardens, as herbalists make extensive use of it. However, it is not listed in the U.S. Pharmacopeia.