Master of Science (MS)



Document Type



The effects and interactions of chemical, cultural, and biological control of red imported fire ant (RIFA) populations were evaluated in two replicated studies in pastures. The first study was conducted from 2005 through 2007 in Washington parish, Louisiana (WP) where the biological control Psuedacteon tricupsis phorid flies were present and at the LSU AgCenter St. Gabriel Research Station in St. Gabriel, Louisiana (SG) where Psuedacteon tricuspis flies were absent. The second study was conducted from May 2009 to May 2010 at St. Gabriel in the presence of phorid flies. In both studies, RIFA population indices in sites treated with methoprene in the presence of phorid flies were significantly less than at pretreatment after one year compared to six months in the absence of phorid flies. In study one, methoprene treatments did not significantly reduce the abundance of phorid flies or Kneallhazia solenopsae infections. In study two, the effects of plowing and methoprene treatments did not interact, and the height of RIFA mounds in plowed pastures was significantly reduced for nine months while methoprene treatment had no effect on mound height. The results of these two studies suggest that the effects of methoprene treatments on RIFA populations are temporally extended in areas where phorid flies are present and that methoprene treatments do not negatively impact the abundance of phorid flies. Since plowing significantly reduces the height of RIFA mounds for nine months and methoprene does not reduce the height of RIFA mounds, plowing is a more effective tool that producers can use rather than methoprene treatments to negate RIFA related damage to hay equipment. However, treatment of areas to reduce RIFA population density to diminish direct impact of RIFA’s on animal and human health can be achieved with methoprene applications, and the temporal and economic benefits of these treatments should be extended in areas where phorid flies are present.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Foil, Lane



Included in

Entomology Commons