cornflower vs fleabane

cornflower

noun
  • A plant of the species Cichorium intybus. 

  • Cornflower blue. 

  • A small annual plant in the family Asteraceae, Centaurea cyanus, usually with bushy blue flowers which grows natively in European cornfields (i.e. wheatfields). 

adj
  • Of a blue colour, as that of the cornflower; cornflower blue. 

fleabane

noun
  • Pluchea spp. (camphorweeds) 

  • Pulicaria spp. (false fleabane), especially common fleabane (Pulicaria dysenterica subsp. dysenterica, formerly Inula dysenterica) 

  • Erigeron spp., especially Erigeron acre (blue fleabane) 

  • Inula spp. (yellowheads) 

  • Also, in subfamily Cichorioideae, Vernonia spp. (ironweeds). 

  • Conyza spp. (butterweeds or horseweed) 

  • mostly in two tribes of subfamily Asteroideae 

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