HEMLOCK DISEASES 187 



Red-Brown Root- and Butt-Rot 



Caused by Polyporus Schweinitzii Pries 



In addition to hemlock, this root- and butt-rot occurs in 

 fir, pine, larch, spruce and arbor-vitse. It is a destructive 

 root-disease of these trees throughout their range. The affected 

 wood is first yellowish and cheesy, later changing to a red- 

 brown, uniform rot. The completely decayed wood is brittle, 

 and is similar in appearance to charcoal. For a more complete 

 description of this disease, see page 294. 



