Hydrangea arborescens, Wild Hydrangea, Seven Barks or Gravel Root, native to eastern N. America. Root extract introduced by S.W. Butler in NJ Medical Reporter in 1851 for treatment of pain associated with passing "gravel" from urinary tract, if calculi is small enough to exit through the urethra. Considered anti-inflammatory and diuretic. | Email: sfoster@stevenfoster.com, or call +1-479-253-2629 for licensing terms and fees. All images © Copyright Steven Foster. Thank you!