root cellar vs subterrane

root cellar

noun
  • A structure built underground or partially underground and used to store vegetables, fruits, and nuts or other foods. 

verb
  • To cellar (food) in a root cellar. 

subterrane

noun
  • A cave or underground room. 

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