achillea vs bloodroot

achillea

noun
  • Any of various plants of the genus Achillea 

bloodroot

noun
  • A North American plant, Sanguinaria canadensis, of the poppy family, which has a red root and sap and a single white flower in early spring. 

How often have the words achillea and bloodroot occurred in a corpus of books? (source: Google Ngram Viewer )