. The decay of timber and methods of preventing it . grow best with a large supply of oxygen; others grow best with-out it. Some require sugars and starches, others do not. All, how-ever, require water. Where there is no water, there will be no fun-gous or bacterial growth. The so-called dry rot fungi require acertain amount of moisture. It is a very erroneous, though wide-spread idea, that they grow in per-fectly dry situations. Much of the rotting of timbercould be prevented by heeding thissimple fact—that without waterthere will be no rot. For this rea-son a tie in a well-drained
. The decay of timber and methods of preventing it . grow best with a large supply of oxygen; others grow best with-out it. Some require sugars and starches, others do not. All, how-ever, require water. Where there is no water, there will be no fun-gous or bacterial growth. The so-called dry rot fungi require acertain amount of moisture. It is a very erroneous, though wide-spread idea, that they grow in per-fectly dry situations. Much of the rotting of timbercould be prevented by heeding thissimple fact—that without waterthere will be no rot. For this rea-son a tie in a well-drained roadbedwill last ever so much longer thanits neighbor in a badly drainedballast, in spite of the absence of treatment, the presence offungi, and ignoring the variability in the timber itself. Whereverorganic food is stored, there the bacteria and fungi are sure togrow with great rapidity if moisture is present. This is one ofthe reasons why sapwood rots so much faster than heartwood. The Fig. 10.—Cracks in wooddue to the solvent actionof Fig. 11.—Cross section of wood, highly ma^nified, showing solvent action of fungi. 20 DECAY OF TIMBER AXD METHODS OF PEEYE^TIXG IT. medullary rays and wood elements of the sapwood have beendescribed as full of protoplasm and reserve sugars, starches, oils, the death of a tree these cells are rapidly invaded by hypha?,which nourish in the sapwood, and soon bring about its entire disso-lution. The heart wood offers no such basis for the beginning offungus growth. It is furthermore protected by antiseptic bodies,such as various resins, the tannins, etc. The sapwood admits of themore ready circulation of water, and in that way favors the rapid
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectagricul, bookyear1902
