club moss vs hogweed

club moss

noun
  • Any of various simple microphyllous vascular plants, of the family Lycopodiaceae, that resemble mosses and produce spores. 

hogweed

noun
  • Certain plants from the genera Ambrosia, Erigeron, or Heracleum. 

  • An umbelliferous plant, of genus Heracleum, most species of which are phototoxic. 

  • Any coarse weedy herb. 

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