overnment scientists at that station, which is
conducted in cooeperation with the University of Wisconsin, is to
check the needless waste of wood. By actual test they find out
all about the wasteful practices of lumbering in the woods and
mills. Then they try to educate and convert the lumbermen and
manufacturers away from such practices.
The laboratory experts have already performed more than 500,000
tests with 149 different kinds of native woods. As a result of
these experiments, these woods are now being used to better
advantage with less waste in the building and manufacturing
industries. A potential saving of at least 20 per cent. of the
timbers used for building purposes is promised, which means a
salvage of about $40,000,000 annually as a result of strength
tests of southern yellow pine and Douglas fir. Additional tests
have shown that the red heartwood of hickory is just as strong
and serviceable as the white sap wood. Formerly, the custom has
been to throw away the heartwood as useless. This discovery
greatly extends the use of our hickory supply.
Heretofore, the custom has been to season woods by drying them in
the sun. This method of curing not only took a long time but also
was wasteful and expensive. The forestry scientists and lumbermen
have now improved the use of dry kilns and artificial systems of
curing green lumber. Now more than thirty-five of the leading
woods such as Douglas fir, southern yellow pine, spruce, gum and
oak can be seasoned in the kilns in short time. It used to take
about two years of air drying to season fir and spruce. At
present the artificial kiln performs this job in from twenty to
forty days. The kiln-dried lumber is just as strong and useful
for construction as the air-cured stock. Tests have proved that
kiln drying of walnut for use in gun stocks or airplane
propellers, in some cases reduced the waste of material from 60
to 2 per cent. The kiln-dried material was ready for use in
one-third the time it would have taken to season the material in
the air. Heavy green oak timbers for wagons and wheels were dried
in the kiln in ninety to one hundred days. It would have taken
two years to cure this material outdoors.
By their valuable test work, scientists are devising efficient
means of protecting wood against decay. They treat the woods
with such chemicals as creosote, zinc chloride and other
preservatives. The life of the average railroad tie is at least
doubled by such
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