BALD CYPRESS DISEASES 99 



rarely found. They also occur on many kinds of deciduous 

 trees and may be associated with wood-rots in these trees. 

 The perennial fruiting-bodies are produced on the lower part of 

 the trunk and are thick, woody, shell-shaped bodies, measuring 

 from three to six by five to ten inches. The upper siu-face is 

 marked with numerous concentric ridges. It is straw-colored 

 and slightly hairy or smooth. The under surface is rose-colored 

 at first but becomes darker with age. The pores are small. 

 The inner substance of the fruiting-body is corky and yellowish 

 brown. 



Cmise. 



The pecky heartwood-rot of bald cypress is caused by Fomes 

 geotropm. The spores from the tubes on the under side of the 

 fruiting-body infect broken branches in the top of the tree. 

 From these points of entrance, the mycelium grows downward 

 into the heartwood. The mycelium becomes abundant in cer- 

 tain centers. At these places the yellow areas appear and finally 

 the pockets are formed. From the first formed yellow areas, 

 strands of the mycelium penetrate the normal wood in all direc- 

 tions without destroying it. At some distance from the original 

 yellow areas, new centers of luxuriant mycelial growth originate 

 and pockets are formed. In this way the wood may become 

 pecky in older trees throughout the entire length of the trunk. 



Pecky cypress is peculiar in the fungus usually ceasing its 

 activity with the formation of the pockets. The cells imme- 

 diately surrounding the pockets are filled with a brown humus 

 compound, which is believed to inhibit the further development 

 of the mycelium. The wood between the pockets is normal and 

 no further decay takes place when the pecky timber is placed 

 under the various extreme conditions conducive to decay. 

 Normal cypress and pecky cypress timbers are equally resist- 

 ant to decay and are the longest lived of the timbers of this 

 country. 



