dendrology vs taxonomy

dendrology

noun
  • the study of trees and other woody plants 

taxonomy

noun
  • The science or the technique used to make a classification. 

  • A classification; especially, a classification in a hierarchical system. 

  • The science of finding, describing, classifying and naming organisms. 

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