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EFFECT OF KILN DRYING, ETC., ON FUNGI IN WOOD. 9 
test pieces with the exception of three cases, namely, the blue-stain 
organism in Pinus strobus, the brown ring-rot in Thuja occidentalis, 
and the brown cubical rot in 7'suga canadensis. In this set, again, 
the blue-stain organism in Pinus strobus resisted the heat in all 
three sizes of test pieces, 1-inch, 2-inch, and 4-inch, and in general 
it stood out as a particularly heat-resistant type of infection in com- 
parison with the rot-producing type. For the other fungi the 2- 
inch test pieces showed positive results in 6 cases and negative results 
in 10 cases, and of the 4-inch pieces 13 gave positive and 3 negative 
results. 
The test pieces of the set subjected to the trial conditions for nine 
hours. upon culturing showed negative results in most cases. ‘The 
blue-stain organism in Pinus strobus was killed in the 1-inch stock. 
In the 2-inch stock the same organism was dead in the outer por- 
tions of the block but alive in the fragment taken from the center of 
the block. In the 4-inch block the organism was alive in all the 
fragments except those taken within a general area extending from 
the edge of the block to approximately 1 inch inward from the edge. 
All of the 1-inch test pieces gave negative results. Of the 2-inch 
stock, all but two pieces gave negative results. These were 7'rame- 
tes pint in Larix laricina (of which only one of the five fragments 
gave positive results) and blue stain in Pinus strobus. Cultures of 
the 4-inch stock showed only 5 positive and 8 negative. The nega- 
tive results in the 4-inch stock showed a steady increase through the 
3, 6, and 9 hour tests. The conditions in this trial test were effective 
in sterilizing all the 1-inch stock, nearly all the 2-inch stock, and 
only about 61 per cent of the 4-inch stock. 
The set subjected for 12 hours gave negative cultures in all but 
two cases. In the 2-inch and 4-inch Pinus strobus pieces the blue 
stain resisted the heat successfully. 
The 24-hour test was effective in killing all the organisms in ail 
the test pieces. 
RUN 8. 
Two sets of test pieces, consisting of test material from both the 
Neopit and Oakridge shipments, were placed in a Tiemann dry kiln 
for periods of six and nine hours, respectively. The temperature 
was maintained at 130° F. and the relative humidity at 100 per cent. 
Test pieces of the Oakridge shipment, 6 by 6 inches and 8 by 8 inches 
square, were used in this test. 
At the end of the test the cultural method showed that after six 
hours the fungi in the centers of the 6 by 6 and 8 by 8 inch test 
pieces were still alive. At the end of the 9-hour test, however, 
all of the test pieces, including the 6-inch and 8-inch pieces, showed 
negative cultures. 
RUN 9. 
Five sets of test pieces of the Neopit material were stacked in a 
Tiemann dry kiln. Steam was introduced gradually into the kiln 
until the recording instruments showed a temperature of 140° F. 
and a relative humidity of 100 per cent. The test started at this 
point, and this temperature and humidity were maintained. 
A set of test pieces was removed from the kiln at the end of 8 
hours, the second set at 6 hours, the third at 9 hours, the fourth at 
91940°—24 2 
