bract vs foliage

bract

noun
  • A leaf or leaf-like structure from the axil out of which a stalk of a flower or an inflorescence arises. 

foliage

noun
  • The leaves of plants. 

  • Fall foliage. 

  • An architectural ornament representing foliage. 

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