Supplemental Calcium Applications to Creeping Bentgrass Established on Calcareous Sand

Abstract

Sand‐based athletic fields and golf course greens may contain large amounts of CaCO3 Calcium is frequently applied to these areas based on the belief that the Ca within the CaCO3 is not readily available for plant use. Our objectives were to determine if Ca applied to creeping bentgrass grown on calcareous sand increases Ca uptake, affects the clipping yield or quality of the grass plant, or affects the availability of other nutrients. A 2‐yr field trial was initiated on a calcareous sand‐based green established with ‘Crenshaw’ creeping bentgrass {Agrostis palustris Huds. [= Agrostis stolonifera var. palustris (Huds.) Farw.]}. Treatments included gypsum (CaSO4), CaCO3, Ca nitrate [Ca(NO3)2·4H2O], and liquid Ca chelate applied across five months at 4.5 g Ca m−2 per month and an untreated control. Urea was added to balance the N found in the Ca(NO3)2 and Ca chelate treatments. Throughout the experiment, there were no differences in tissue Ca content, visual quality, or clipping yield in response to the Ca treatments. With the exception of the CaSO4 treatment in 1999, application of Ca did not significantly affect the leaf concentrations of the other nutrients. During the first year, creeping bentgrass grown in plots receiving CaSO4 contained 11% less tissue Mg than the creeping bentgrass in the control plots. Supplemental Ca applications to creeping bentgrass established on calcareous sand had no beneficial effects.