bugleweed vs ground pine

bugleweed

noun
  • Ajuga, a group of herbs used for ground cover; bugle 

  • Any of the aromatic herbs in genus Lycopus, especially Lycopus virginicus, water horehound 

ground pine

noun
  • Ajuga, a genus of herbaceous flowering plants in the mint family Lamiaceae, with most species native to Europe, Asia, and Africa; also, specifically 

  • Diphasiastrum complanatum (syn. Lycopodium complanatum) (northern running-pine), a species of clubmoss native to dry coniferous forests throughout the holarctic region. 

  • Lycopodium obscurum (princess pine), native to eastern North America 

  • Lycopodium clavatum (stag's-horn clubmoss, running clubmoss) 

  • Ajuga chamaepitys (yellow bugle), native to Europe, the eastern part of the Mediterranean, and North Africa 

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