Invasive mound-building imported fire ants (Solenopsis spp.) actively modify the physical and biogeochemical properties of soil impacting soil quality as well as crop nutrient management at field and landscape scales. However, the relative stability of ant-mediated soil modifications across seasons is largely unknown. Nutrient concentrations were concurrently analyzed from ant mounds and adjacent undisturbed soils collected from a warm-season turfgrass (Cynodon dactylon x C. transvaalensis – Tifway 419) production agroecosystem in the Southern Mississippi Valley Silty Uplands. Hyperspectral data were also acquired from ant mound surfaces and undisturbed soil locations to test ground-based detection capabilities across seasons. Sampling conducted during key nesting cycle phases revealed that during late Summer (colony biomass maximum), total C, total N, C/N ratios, organic matter (OM), and Zn concentrations as well as pH of mound soils were significantly greater than control soils; these trends persisted across seasons, with one exception (total N – in December, which coincided with ant brood minimum). Soil P, K, Ca, Mg, and S concentrations from ant mound soils were substantially greater than undisturbed soils during Autumn, Winter, and Spring with one exception (S – in late Spring, which coincided with peak alate production). The complexity of biogeochemical interactions within ant mound soils was most likely enhanced by plant uptake and excretion in the rhizosphere, seasonal shifts in mound soil biota, and continuous soil mixing by colony workers. Spectral reflectance patterns of ant mound soil surfaces were most heavily influenced by textural, structural and moisture contrasts compared to undisturbed bare soils across seasons.