Christmas berry vs wintergreen

Christmas berry

noun
  • Synonym of toyon (“plant or its berry”) (Photinia arbutifolia, syn. Heteromeles arbutifolia) 

  • Synonym of spiceberry (“plant or its berry”) 

wintergreen

noun
  • Some species of the herbaceous genus Trientalis, in family Primulaceae (chickweed wintergreen) 

  • Genus Chimaphila (prince's pine, pipsissewa) 

  • The aroma of the oil, methyl salicylate, however derived. 

  • Gaultheria procumbens, native to North America, having solitary white flowers and aromatic leaves (checkerberry or teaberry) 

  • Genus Orthilia 

  • The spicy red berries of Gaultheria procumbens. 

  • Genus Pyrola, native to northern temperate and Arctic regions. 

  • Chimaphila maculata – striped wintergreen, pipsissewa 

  • The oil, methyl salicylate, obtained from these berries. 

  • Gaultheria humifusa – alpine wintergreen 

  • Genus Moneses 

  • Gaultheria ovatifolia – western teaberry or Oregon spicy wintergreen 

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