loam vs subsoil

loam

verb
  • To cover, smear, or fill with loam. 

adj
  • Made of loam; consisting of loam. 

noun
  • A mixture of sand, clay, and other materials, used in making moulds for large castings, often without a pattern. 

  • A type of soil; an earthy mixture of sand, silt and clay, with organic matter to which its fertility is chiefly due. 

subsoil

verb
  • To turn up the subsoil of. 

noun
  • The layer of earth that is below the topsoil. 

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