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HEART EOT OP PT^BOXYLON UTILE (SNEEZE WOOD) 

 CAUSED BY FOMES BIMOSUS (BEEK). 



By Paul A. van dbk Bijl, D.Sc, P.L.S., Mycologist, Department of 

 Agriculture, Union of South Africa. 



(With Plates XXXIX-XLIV.) 



Table of Contents. 



PAGK 

 Introduction ...... . 215 



Distribution of Fames rimosus 



General account of the disease . 



Action of the fungus on the wood 



Mycelium of the fungus in the host 



Description of the fungus 



Control of heart-rot caused by Pomes rimosus 



Summary .... 



Acknowledgments 



Explanation of illustrations 



217 

 217 

 219 

 220 

 221 

 222 

 224 

 224 

 226 



Inteodtjcticn. 



Ptseroxylon utile (Eng., Sneezewood; Dutch, Nieshout; Kafir, Um-tati) 

 is a tree which appears to have but few enemies. Sim* writes : " It is 

 strange that a timber so durable when dead and dry should be, while alive, 

 subject to attack by a Polyporus, which not only acts on the sapwood, but is 

 even more partial to the heartwood, and in many cases trees are found to 

 consist of only a cylindrical shell, the centre being completely gone ; but 

 even in such cases the timber, when once dead, is everlasting and proof 

 against fungus and white ants. Two borers occasionally affect the tree, the 

 smaller acting only in the sapwood and forming numerous small channels, 

 while the larger bores through the heart wood, leaving one tunnel J in. 

 diameter." The Polyporus, mentioned by Sim, is evidently Fames rimosus, 

 Berk., the fungus treated in this article. 



On the timber of this tree Simf remarks : " The timber is one of the 

 hardest and heaviest in the Colony ; it is dense and close-grained, strong and 

 tough, and heavily charged with oily resin. It is of a yellowish colour, often 



* Sim, T. K., The Forests and Forest' Flora of Cape Colony, p. 168. 

 t Sim, T. K., op. cit., p. 167. 



