hawthorn vs quickthorn

hawthorn

noun
  • Any of various shrubs and small trees of the genus Crataegus having small, apple-like fruits and thorny branches 

quickthorn

noun
  • The may-tree, any species of Crataegus or the species Crataegus monogyna. 

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