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CIRCULAR 8 5 3, U. S. DEPARTMENT OF AGRICULTURE 



Figuke 7. — Root of seedling sweet orange tree attacked by Clitocybe root rot, 

 showing blackish xylostroma extrusions developed through longitudinal fis- 

 sures in the bark. Natural size. 



Figure S. — Clitocybe tabescens fruiting at base of Brazilian Butia palm attacked 

 by root rot. Photo by Dr. George F. Weber. 



at the bases of trees or shrubs that have been infected by it for some 

 i [me (fig. 8). The presence of one or more clusters of these growing 

 from the roots or bases is an infallible sign that the root systems have 

 been more or less extensively invaded by the fungus, even though 

 symptoms of decline may not be apparent. 



