Pedoturbation of a Forest Soil by Fire Ants

Abstract
The influences of the imported fire ant (Solenopsis invicta) on the mixing of forest soils on three sites in north Louisiana were examined. Soil bulk density, pH, percent organic matter, and concentrations of P, K, Ca, and Mg were compared for samples from ant mounds vs. adjacent undisturbed soil at two depths. In surface samples bulk density was lower and organic matter, P, K, Ca, and Mg were higher on the mounds. Soil pH did not change. In subsurface comparisons only organic matter and K differed and were higher in the mound samples. Results are discussed in terms of the depth of ant activity, the quantity of soil excavated, and the organic matter, P, K, Ca, and Mg content of that soil. Questions are raised regarding the role of fire ants in the decomposition of tree stumps.