Submitted to: Midsouth Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/23/2009
Publication Date: 7/1/2009
Citation: Vogt, J.T. 2009. Nature and severity of imported fire ant (Hymenoptera: Formicidae) infestations on the Mississippi River Levee. Midsouth Entomologist. 2: 78-83.
Interpretive Summary: The Mainline Mississippi River Levee stretches some 5,600 km from Cape Girardeau, MO to the Gulf of Mexico, and everything south of Lauderdale County, TN is subject to infestation by imported fire ants which may be a concern due to their soil disturbing, mound building activities. Mound density on the levee slopes ranged up to more than 200 mounds per acre with more mounds located on the landside and riverside levee slopes than on the flat area adjoining the landside slope. The results of this study indicate that imported fire ant mounds are very abundant on the slope of the levee subjected to scouring during flooding, and additional work is needed to assess their potential impact on levee performance during periods of high water.
Technical Abstract: Infestations of imported fire ant (Solenopsis invicta Buren) were mapped and quantified at four sites on the Mainline Mississippi River Levee in Mississippi. Smaller mounds predominated in areas of high insolation, and overall ant density (measured by above-ground mound volume and mound density) appeared to be highest at moderate insolation levels and lowest in areas of high insolation. More imported fire ant colonies were located on the levee slope than the adjoining landside berm. Despite trends in mound size and overall ant density, colonies were encountered on all parts of the levee, making adequate coverage of the infested area from the road atop the levee a primary concern in potential control programs. Severity of infestation (in some areas > 500 mounds ha-1) warrants further investigation into the physical effects of mound building on the levee and potential to impact levee performance during periods of high water.