EFFECT OF KILN DRYING, ETC., ON FUNGI IN WOOD. 19 
Minch (4) has shown that for a blue-stain fungus (Ceratostomella 
coerulea. Miinch) in the sapwood of Scotch pine (Pinus sylvestris 
L.) the optimum moisture content of the wood lies between 33 and 
74 per cent, based upon the oven-dry weight. Above and below these 
limits the activity of the fungus decreases, and at 143 per cent no 
prowth was noted. At 28 per cent little growth was evident. The 
Saime writer also states that the moisture content favorable for the 
blue-stain fungus agrees in general with the moisture requirements 
of certain wood-destroying fungi. 
Snell (7) has reported on one series of experiments in which he 
used Lenzites sepiaria, L. trabea, Trametes serialis, Fomes roseus, 
and Lentinus lepideus in loblolly-pine sapwood (Pinus taeda 1.) 
and Sitka spruce (Picea sitchensis), presumably heartwood. He 
found that the results upon loblolly-pine sapwood agieed very closely 
with those of Miinch on Scotch pine. Very little decay was recorded 
when the quantity of water in the wood was below the fiber satura- 
tion point, a moisture content of 25 per cent in terms of the oven- 
dry weight of the wood. With the increase in moisture content the 
decay increased, and the greatest development of decay occurred 
between 33 and 42 per cent (or 49 and 72 per cent based on the 
oven-dry weight). At 50 per cent there was little decay, and no 
decay was noted at 60 per cent (150 per cent, oven dry). With 
spruce the decay began a little below the fiber saturation point, and 
the greatest development was noted between 30 and 57 per cent (43 
and 133 ¢ cent, oven dry). At 67 per cent (203 per cent, oven 
dry) neither penetration by the hyphe nor decay was noted. 
These experiments indicate that a moisture content considerably 
above the fiber saturation point of wood is required for the optimum 
development of at least certain fungi within wood. How long 
this optimum condition must be maintained to produce decay in 
stored lumber is not known, nor are there any figures to show 
whether alternate wetting to the fiber-saturation point and above 
and drying to 17 per cent and lower is favorable or unfavorable to 
fungous development. In regions where the rainfall is heavy and 
continuous over long periods the unprotected and poorly protected 
lumber would unquestionably develop wood-inhabiting fungi. It 
is doubtful whether lumber properly dried and carefully stored 
under cover would absorb sufficient moisture from a humid atmos- 
phere to sustain continuous fungous growth within the wood. 
With these facts as a basis, it seems reasonable to suppose that 
wood properly kiln dried will be sterilized and that if it is then 
properly stored in dry well-ventilated piles protected from all mois- 
ture (except the moisture absorbed from the air) the stock will re- 
main bright and sound. 
SUMMARY. 
The need is shown for some practical method or methods of 
sterilizing wood against the fungi inhabiting it, and the wide appli- 
cation of such methods to the wood producing and consuming indus- 
tries is indicated. 
The tests carried out show that a long list of wood-inhabiting 
fungi in a variety of woods can effectively be arrested in their de- 
yelopment through sterilization by heat, — 
