summer vs summer-tree

summer

verb
  • To spend the summer, as in a particular place on holiday. 

noun
  • A machine or algorithm that sums. 

  • Someone with light, pinkish skin that has a blue undertone, light hair and eyes, seen as best suited to certain colors of clothing. 

  • A person who sums. 

  • One of four seasons, traditionally the second, marked by the longest and typically hottest days of the year due to the inclination of the Earth and thermal lag. Typically regarded as being from June 21 to September 22 or 23 in parts of the USA, the months of June, July and August in the United Kingdom and the months of December, January and February in the Southern Hemisphere. 

  • year; used to give the age of a person, usually a young one. 

  • A horizontal beam supporting a building. 

adj
  • the hottest season of the year 

summer-tree

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