bracket fungus vs mildew

bracket fungus

noun
  • Any of various fungi of the family Polyporaceae, whose fruiting bodies form on trees and resemble shelves. 

mildew

noun
  • A growth of minute powdery or webby fungi, whitish or of different colors, found on various diseased or decaying substances. 

verb
  • To taint with mildew. 

  • To become tainted with mildew. 

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