goat's-beard vs hawthorn

goat's-beard

noun
  • A woodland plant of the family Rosaceae, Aruncus dioicus. 

  • A yellow-flowered Eurasian plant, of the genus Tragopogon. 

hawthorn

noun
  • Any of various shrubs and small trees of the genus Crataegus having small, apple-like fruits and thorny branches 

How often have the words goat's-beard and hawthorn occurred in a corpus of books? (source: Google Ngram Viewer )