Thatch and Quality of Tifway Bermudagrass Turf in Relation to Fertility and Cultivation 1

Secondary 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.