trifoliate orange vs wild orange

trifoliate orange

noun
  • A shrub, Citrus trifoliata, mostly grown as a rootstock for other citrus. 

wild orange

noun
  • Several species of wild Citrus fruit, especially Citrus macroptera. 

  • Capparis mitchellii, a non-citrus plant species that contains notable amounts of vitamin C. 

How often have the words trifoliate orange and wild orange occurred in a corpus of books? (source: Google Ngram Viewer )