crackleberry vs highbush blueberry

crackleberry

noun
  • The high-bush huckleberry, Gaylussacia baccata, native to eastern North America, or the fruit of this shrub 

  • An imaginary shrub, or the fruit of this shrub 

highbush blueberry

noun
  • The common species of blueberry, Vaccinium corymbosum, grown for its fruit. 

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