blow down vs mow down

blow down

verb
  • Synonym of dirty down 

  • To knock over with an air current, most often wind. 

mow down

verb
  • To kill or slaughter, or to injure by knocking down, especially in large numbers and in a ruthless manner. 

  • To cut down, especially in large numbers. 

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