TREES AND TIMBER 



417 



with the upper surface in early stages a bright orange-red ; 

 later they are sulphur-yellow both above and below. The 



V. 



X: 



v: 



# 



;// 



Fig. 179. — Polyporus sulphureus showing effect upon wood of oak tree. After von 

 Schrenk. 



upper surface when bruised is brown. The sporophore is 

 soft and fleshy when young, growing harder with age until 



2e 



