ryegrass vs seedling

ryegrass

noun
  • A collection of plants of any of the species, as in a lawn or field. 

  • Any of several species of tufted grasses of the genus Lolium. 

seedling

noun
  • A young plant grown from seed. 

  • a tree smaller than a sapling. 

  • one grown in a nursery for transplanting. 

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