260 MANUAL OF TREE DISEASES 



of the shelves of the fruiting-body cause infection in wounds at 

 the base of the tree. The hfe history and control of the wood- 

 rot fungi will be found discussed on page 64. 



Reference 



Long, W. H. Three undescribed heart-rots of hardwood trees, espe- 

 cially of oak. Jour. Agr. Res. 1 : 109-128, pis. 7-8. 1913. 



White Wood-Rot 



Caused by Pomes Everhartii (BUis and GaU.) Sehrenk 



This wood-rot has been found common in black jack oak and 

 probably occurs in other species. It has not been fully de- 

 scribed. It is said to resemble closely the common white wood- 

 rot caused by Fames igniarius. The rot extends into the sap- 

 wood. The sporophores of the causal fungus also resemble 

 those of Fames igniarius. They are shelf -like and rarely hoof- 

 shaped. The upper surface is at first brown, but later becomes 

 black and checked by many fissures. The under surface and 

 margin are brown. The pores in the under surface are very 

 small. 



Reference 



Sehrenk, Hermann von, and Spaulding, P. Heart-rot of oaks caused 

 by Fomes Everhartii. In Diseases of deciduous forest trees. 

 U. S. Dept. Agr. Bur. PL Ind. Bui. 149 : 48, pi. 3. 1909. 



White Butt-Rot 



Caused by Fomes applanatus Fries 



The heartwood of the lower part of the trunk and roots of 

 oak is sometimes destroyed by this rot. The wood becomes 

 whitish and light in weight but retains its fibrous structure. 

 The rotted wood when split shows numerous sinuous white- 

 stuffed tunnels resembling the work of insects. The sporo- 

 phores of the causal fungus are often found at wounds near the 



