arborvitae vs eastern whitecedar

arborvitae

noun
  • Any of several North American or Asian conifers, of the genera Thuja and Thujopsis or the species Platycladus orientalis, grown for timber or ornament. 

  • The white nerve tissue of the cerebellum that has a branching structure. 

eastern whitecedar

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