State Museum of Natural History. 



93 



to ten inches thick, should first be laid down, and the lumber piled on 

 them in tiers, Avith narrow sticks between each board at the ends and 

 centers. Grass and weeds should not be allowed to grow near the 

 piles of lumber, impeding the circulation of air under them. 



Large timber should be seasoned under sheds and not exjjosed to 

 the rays of the sun, as the latter dries an exterior portion so rapidly 

 that it prevents the proper escape of moisture from the outside, and 

 internal decay is liable to occur. 



If timber, ties or boards are piled in close contact, and remain so 

 for any length of time, dampness will revive and start the growth of 

 mycelium. It is not uncommon to see large sticks of timber, 

 especially for freight cars, taken into the shops partially covered by 

 mycelium, dressed, framed, put into cars and then painted, thus com- 

 pleting the essential condition for slow but certain decay. Such wood 

 has only one-fourth to one-third the life of seasoned wood. 



Boards, especially those used for sheathing freight cars, when piled 



in close contact, in 

 summer, are attacked 

 in a short time by 

 fungi, which discolor 

 the wood by filling the 

 cells with growths, 

 often similar to those 

 shown in Fig. IV. 



The species of fungi 

 which discolor the sap- 

 wood and then set uf) 

 fermentations are ex- 

 ceedingly numerous 

 and grow with great 

 raj)idity. Some of the 

 forms found in white 

 pine are spheres re- 

 sembling those shown 

 in Fig. IV. 



This wood, on being- 

 dried, will remain dis- 

 colored, but the sea- 

 soning will check the 

 decay. Such boards, when put into cars and jDaiuted, quickly decay 

 when moisture reaches the unjDainted surface. This class of decay is 



Fig. IV. Magnified 150 diameters, showiog fungus 

 gi'owths discoloring tlie sap-wood of white pine. 



