cup-plant, Silphium perfoliatum

Flowers in the genus Silphium tend to look a very much alike. But the leaf forms are marvelously varied. Cup-plant has large leaves that clasp the stem. The bases form cups that do collect water. It's a big plant, mostly taller than we are (hence an image with the sky as background). It has recently been discovered that cup-plant is a very good crop for producing biomass for biogas. As a crop, it needs very little maintenance once it is established. Due to increased cultivation, it has gone from a sometime rarity to invasive in some places. Indians used it medicinally, perhaps most often to help with problems during pregnancy. Cup-plant grows in AL, AR, CT, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI(T), MN, MO, MS, NC, ND, NE, NJ, NY, OH, OK, PA, SD, TN, VA, VT, WI, WV, ON, and QC. Isabella Co MI, 8/23/13. Aster family, Asteraceae.