In Medical Botany page 245, 2nd Ed.  It describes the use of Ehretia cymose (Boraginaceae). Research Walter did with L Avioli at the med school showed a 112% increase in bone turnover using aqueous extracts.  I have used it myself and can attest to its usefulness.  To make a poultice grind up the leaves in a blender with distilled water.  Filter through cheese cloth to retrieve the quid.and apply with cheesecloth to the affected area.  Keep the water extract to recharge the quid.  Lewis WH and A