August 4, 2004 (ENS): A U.S. Forest Service
researcher looking for ways to prevent fungi from causing
wood to decay may have discovered an important new tool
in the battle against termites.
Microbiologist Frederick Green III discovered that a
commercially available naphtha based compound called
N-hydroxynaphthyalimide (NHA) worked well to prevent
decay causing fungi from damaging wood and was effective
at killing common Eastern subterranean termites.
Green reported his findings to two termite experts,
entomologists M. Guadalupe Rojas and Juan Morales-Ramos,
at the USDA's Agricultural Research Station in New Orleans.
Termites cause an estimated $2 billion in damage annually
in the United States and are a major problem in the
warm and humid Southeast, where Formosan subterranean
termites (FSTs) have proven to be especially destructive
and difficult to eradicate.
This type of termite is an invasive species that arrived
in the U.S. about 50 years ago and are responsible for
an estimated $1 billion in damage annually to buildings
and living trees.
FSTs are large and reproduce prolifically, establishing
colonies that number 10 million or more termites --
compared to only 300,000 individuals in a typical colony
of native Eastern subterranean termites.
Termites sometimes travel as far as 100 yards from
their nests in search of food and can eat through plastic
pipe and thin metal.
They also have demonstrated an ability to survive standard
termidicide treatments, in part by avoiding traditional
termite baits, and in some areas had displaced the less-destructive
native Eastern termites.
In areas infested with FSTs, homeowners and others
often have to resort to expensive physical barriers
to prevent FSTs from damaging property.
Both Rojas and Morales-Ramos were members of a multi-agency
task force created by the Agriculture Department to
find a solution to the FST problem.
Rojas and Morales-Ramos developed a cellulose attractant
to combine with the NHA. It proved so appealing to the
termites that even the Formosan subterranean termites
would carry the bait containing NHA back to their nests.
In field tests in Louisiana and Mississippi, entire
colonies of Formosan subterranean termites were eliminated
in a matter of months, depending on the size of the
Because the NHA termite bait is effective at low doses
and, unlike most termidicides, contains no heavy metals,
it is considered environmentally friendly and cost effective.