Aaron's rod vs great mullein

Aaron's rod

noun
  • Verbascum thapsus, the great mullein, common mullein, or hag-taper. 

  • Hylotelephium telephium (syn. Sedum telephium; orpine, livelong, or live-forever). 

  • A rod-shaped molding decorated with an entwined snake, and sometimes leaves, vines, and/or scrolls. 

  • Goldenrod, the Solidago genus of North American plants with yellow flowers. 

great mullein

noun
  • A common herb of Europe and neighboring Africa and Asia, but widely naturalized elsewhere, Verbascum thapsus, having a flannel-like texture from course plant hairs and a tall, straight flower stalk. 

How often have the words Aaron's rod and great mullein occurred in a corpus of books? (source: Google Ngram Viewer )