black raspberry vs blue raspberry

black raspberry

noun
  • The fruit of any of these species. 

  • A plant belonging to either of two closely related species, Rubus leucodermis or Rubus occidentalis, both native to North America. 

  • Rubus coreanus, native to Korea, Japan, and China 

blue raspberry

noun
  • An artificial flavor used in candy and soft drinks, which, despite the name, is not derived from any species of raspberry. 

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