FIR DISEASES 



169 



Brown Heartwood-Rot 



Caused by Fames officinalis Fries (= Fames laricis (Jacq.) Murrill) 



Douglas & is often severely damaged by this heartwood-rot 

 in the Northwest. Larch, pine and other conifers are affected 

 by the same disease throughout western United States. The 

 decayed wood re- 

 sembles the brown 

 checked wood-rot 

 caused by Poly- 

 porus sulphureus 

 (see page 247). In 

 the final stages of 

 decay, the heart- 

 wood is brownish 

 or red-brown. 

 Felts of mycelium 

 form in checks in 

 the brown wood 

 (Fig. 26). The 

 fruiting-bodies of 

 the causal fungus 

 are large hoof- 

 shaped or globose, 

 with a rough 

 chalky upper surface 

 has a bitter taste 



Tig. 26. — Brown heartwood-rot of Douglas fir. 



The inner substance of the sporophore 

 A more complete discussion of this heart- 

 wood-rot will be found under larch diseases, page 216. 



Brown Root- and Butt-Rot 



Caused by Fames annosus Fries 



This rot of the wood of the roots and lower part of the 

 trunk of fir is occasionally found in the forests of the North- 



