century plant vs pita

century plant

noun
  • An agave (Agave americana) originally from Mexico but cultivated worldwide. 

pita

noun
  • A fiber obtained from the Agave americana and related species, used for making cordage and paper. 

  • A flat bread pouch used for making sandwiches such as gyros or falafels. 

  • The plant which yields the fiber. 

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