Heart Hot of Ptseroxylon utile (Sneezewood) . 223 



removal of the possible sources of infection. Wherever it is intended to 

 conserve forest areas, a careful search should be made for all trees infected 

 with this fungus, and they should be promptly removed. This is the more 

 important, since, as already stated, in South Africa Fames rimosus does not 

 limit itself to Ptseroxylon utile, but attacks a large number of trees belonging 

 to different orders. 



The presence of the sporophores of the fungus on a tree is evidence of 

 the presence of heart rot and of the necessity of removing the tree. Sporo- 

 phores on trees should be removed wherever found. 



The practice of leaving uncut, trees affected with heart rot is wrong from 

 the standpoint of proper forest sanitation, for it merely enables the causal 

 fungus to develop its fructifications and exposes the coming generation to a 

 continuous danger of becoming infected as soon as they have developed 

 heart wood and the opportunity offers itself. Fames rimosus is not known 

 to form new fructifications after the attacked tree is dead, and a proper 

 look-out for and the destruction of living diseased trees as well as the 

 sporophores of the fungus should go a long way towards lessening infection 

 in the forests. 



The foregoing would appear to be the most practical methods for con- 

 trolling this disease in large forests. On a small scale it may perhaps be 

 necessary to give attention to individual trees ; assist the natural pruning 

 tendency of the tree and trim all wounds prioi to painting them over with 

 some disinfectant. The disinfectant should have suificient penetrating power 

 to infiltrate into the wood for some considerable distance. Coal-tar creosote 

 heated up until thoroughly liquid will be found as good as any. The 

 disinfecting is especially advisable where the wounds are large. 



Humphrey and Fleming * have recently published an interesting paper 

 on the toxicity to fungi of oils and salts, and particularly those used in wood 

 preservation. In their research they included two wood-destroying fungi — 

 Fames annosus, Fr., and Fames pinicala (Sw.) Fr. They find the preservatives 

 used act in a considerably different manner on these two fungi and the 

 former to be as a rule more resistant. 



Mention should here also be made of a recent paper by Howef on the 

 effects of various dressings on pruning wounds of fruit trees. The author 

 found untreated wounds to heal more rapidly, and on peach trees the 

 substances experimented with caused so much injury that the author holds 

 wounds on peach trees should never be treated with any of them. The 

 author's "conclusions are that there is nothing to show that it is worth while 



* Humphrey, C. J., & Fleming, B. M., "The Toxicity to Fungi of Various Oils and 

 Salts, particularly those used in Wood Preservation." U.S.A. Dept. of Agriculture, 

 Bureau of Plant Industry, Bull. 227, 1915. 



t Howe, G. H., " Efeect of Various Dressings on Pruning "Wounds of Fruit Trees," 

 New York Agrio. Exp. Station (General), Bull. No. 396, 1915. 



