flora vs phytology

flora

noun
  • A book describing the plants of a country, region, time, etc. 

  • Plants considered as a group, especially those of a particular country, region, time, etc. 

  • The microorganisms that inhabit some part of the body. 

phytology

noun
  • the study of plants; botany 

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