92 Forty-first Annual Report on the 



The mycelium of this fungus is usually pure white, and is not 

 killed by freezing in the wood. In bridges it is very destructive. 



Trametes Pirn is also found upon ties of this wood, but is confined to 

 the portions above ground. It will grow and fruit with less moisture 

 than Lentinus lejjideus, but as far as observed, its rapidity of destruc- 

 tion is not so great. 



The fungus shown in Fig. Ill appears on the sap-wood of yellow 

 pine, giving it a dark, dingy appearance, and if 

 the dampness continues fermentations are set up, 

 destroying the wood. 



Sphceria Pilifera attacks the sap-wood, discolors 

 and quickly destroys this portion of the wood 

 Fig III Sphan-ia pili- ^^der favorable conditions for its growth. The 

 dlatue^ers"^^^'^^^^^ ^^^ resinous matter in yellow jnne does not jDrotect it 

 in out-door situations, from attacks of the fungi mentioned. 



The heart wood of yellow pine is so dense and firm that it is not 

 readily penetrated by antiseptics. The same remarks in regard to 

 imbedding white oak ties apply to this wood. In buildings, yellow 

 pine is attacked by Merulius lacrymans,Fr.,vfh.eve it is warm and damp 

 and the air stagnant. 



White pine, Finns Strobus, L., when used in bridges and trestles, is 

 attacked by Lentinus lepideus, Fr., Agaricus melleus Vahl., Polyporus 

 Vaillantii Fr. and, in warm inclosures, Merulius lacrymans Fr. Both 

 the latter are very destructive. 



There are many other woods whose structure is well adapted to 

 their use as railroad ties, but which are so quickly destroyed by fungi 

 as to be of no value unless judiciously treated. These are the beech, 

 birches, elms and maples. 



The above will be sufficient to call attention to the practical impor- 

 tance of a study of the fungi, in an economic sense as applied to the 

 decay of wood. 



The following simple but effective measures for the preservation of 

 wood can at once be put in practice : 



Timber, ties and boards should be seasoned before using, except 

 when submerged. Green wood, according to the sj^ecies, contains from 

 twenty-five to forty-eight per cent of its weight of sap or moisture, 

 and fully one-half these amounts must be removed to j)revent decay 

 in lumber painted on one side, or large sticks of timber painted on 

 all sides, as buffers and car sills, transoms, truck bolsters and 

 timbers. 



All lumber and timber 'should be piled so there can be a free circu- 

 lation of air around and between each board or stick. -Stringers, six 



