Bahiagrass and soil responses to lime sources and application levels

Abstract

AbstractThe increasing cost of lime and the agronomic problems associated with soil acidity management has prompted the need to re‐examine management strategies to correct soil pH while maintaining forage productivity. This study evaluated the effect of different lime sources (pelletized dolomitic limestone [dolomite] and hydrated calcitic limestone [Hi‐Cal]) and application levels (0, 1.1, 2.2, and 4.4 Mg ha–1 yr–1) on soil chemical properties and bahiagrass (Paspalum notatum Flügge) responses in 2014 through 2017. Forage and soil responses were monitored during the 4‐yr period, and residual lime effect was also evaluated 3 yr after liming ceased (2020). Liming increased bahiagrass herbage accumulation by 12% relative to control; however, no effect of lime source (P = .6), application level (P = .16), or their interaction (P = .11) was observed. Both lime sources increased tissue P, Mg, Ca, and S concentrations relative to control; however, tissue B, Zn, Mn, Fe, and Cu generally decreased. A single application of Hi‐Cal or two annual applications of dolomite increased soil pH from 4.5 to the recommended level of 5.5 for bahiagrass. Soil pH (0–45 cm depth) increased with repeated lime applications particularly in Hi‐Cal treatments, but no adverse effects on bahiagrass were observed. Soil pH remained above the recommended level 3 yr after liming ceased. Despite the lack of treatment effect, soil P and K levels decreased with time likely because of nutrient removal with harvested forage. Proper P and K fertilization along with soil pH management are key components to maintain long‐term productivity of bahiagrass.