American winterberry vs red nightshade

American winterberry

noun
  • Ilex verticillata, a species of holly native to eastern North America in the United States and southeast Canada, from Newfoundland west to Ontario and Minnesota, and south to Alabama. 

red nightshade

noun
  • Phytolacca americana syn. Phytolacca decandra 

  • Solanum villosum 

How often have the words American winterberry and red nightshade occurred in a corpus of books? (source: Google Ngram Viewer )