Thatch and Quality of Tifway Bermudagrass Turf in Relation to Fertility and Cultivation1

Abstract

AbstractSecondary cultural practices, such as core aeration, vertical mowing, and topdressing, are being used on homelawn turf to a greater extent, even though specific problems may not warrant their application. In a field study (clayey, kaolinitic, thermic Typic Hapludult soil), we applied secondary cultural practices on ‘Tifway’ bermudagrass [Cynodon dactylon (L.) Pers. ✕ C. transvaalensis (Burtt‐Davis)] in conjunction with annual N rates of 98, 196, and 296 kg ha−1 and K at 49, 98, and 196 kg ha−1. Neither N nor K influenced thatch accumulation, but a minimum of 196 kg N ha−1 was necessary for adequate shoot density and color. The 49 kg K ha−1 resulted in as good or better shoot density and color than did higher K rates. Three to four times more dollar spot (Moellerodiscus spp. and Lanzia spp.) occurred at the lowest N rate, while K had much less influence on disease incidence. Core aeration applied once or twice per year caused a loss of stand density and did not reduce thatch accumulation regardless of whether cores were removed or returned. Vertical mowing twice per year decreased thatch by 8% but shoot density was adversely affected. At the end of 4 yr, topdressing with sand reduced thatch by 44 to 62% for one or two applications, respectively, while maintaining adequate shoot density and color. Increasing N or K did not offset the adverse effects of core aeration or vertical mowing. Thus, under homelawn conditions, core aeration and vertical mowing should only be used if a specific problem exists and not as routine practices to prevent thatch accumulation.