black alder vs white alder

black alder

noun

  • American winterberry, Ilex verticillata. 

  • Wood or other product of the tree. 

  • A tree (Alnus glutinosa), of many practical uses, growing in moist conditions in Europe. 

white alder

noun

  • American winterberry (Ilex verticillata). 

  • Grey alder (Alnus incana) 

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