common chicory vs horseweed

common chicory

noun
  • Cichorium intybus, a somewhat woody perennial herbaceous plant of the dandelion family, many varieties of which are cultivated for salad leaves. 

horseweed

noun
  • A plant of the species Cichorium intybus 

  • Any of various flowering plants of the genus Conyza. 

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