green woodpecker vs thousand-leaf

green woodpecker

noun
  • A European bird, Picus viridis. 

thousand-leaf

noun
  • Achillea millefolium or common yarrow, a flowering plant widespread in the temperate Northern Hemisphere, featuring finely divided leaves. 

How often have the words green woodpecker and thousand-leaf occurred in a corpus of books? (source: Google Ngram Viewer )