bracken vs hedgerow

bracken

noun
  • An area of countryside heavily populated by this fern. 

  • Any of several coarse ferns, of the genus Pteridium, that form dense thickets; often poisonous to livestock. 

hedgerow

noun
  • a row of closely planted bushes or trees forming a hedge 

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