This Is AuburnElectronic Theses and Dissertations

Mowing Height, Nitrogen Rate and Source Effects on Establishment and Maintenance of Tifway and TifSport Bermudagrass




Hicks, Christy

Type of Degree



Agronomy and Soils


Hybrid cultivars of bermudagrass (Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt-Davy) are the predominant turfgrasses used on golf courses and athletic fields throughout the southeastern United States, and in warm, tropical climates worldwide. Hybrid bermudagrass provides a dense, high quality turf, but does require more intensive maintenance than common bermudagrass. ‘Tifway’ and ‘TifSport’ are two cultivars of hybrid bermudagrasses grown on athletic fields, lawns and fairways. Tifway is a chance F1 hybrid that appeared in seeds of C. transvaalensis and was released in 1960. Currently, it is still the most popular hybrid bermudagrass in use on southeastern turfed landscapes. TifSport is an artificial cobalt 60-induced mutant of the cold tolerant cultivar Midiron, and is a more recent release. TifSport has better cold tolerance and is a patented cultivar, ensuring genetic purity and uniformity. The objectives of this research were to: 1) examine the effect of mowing height and N rate on quality of established Tifway and TifSport hybrid bermudagrass, and 2) examine the effect of N source and N rate on establishment of TifSport and Tifway hybrid bermudagrass in newly sprigged fields. Two year studies of each experiment were conducted, with the establishment study conducted in 2002 and 2004, and the management study conducted in 2002 and 2003. In both studies there were 4 replications of the treatments, with the treatments arranged in strip-strip plot designs. For the establishment study treatments included cultivar (Tifway or TifSport), N source (Ammonium nitrate or calcium nitrate), or N rate. For the management study treatments were cultivar, N rate and mowing height. Data collection included percent establishment, recovery from wear, clipping yield, dry weight of stolons/rhizomes, and resistance to tearing. In the establishment study TifSport initially grew in more quickly than Tifway, but such differences were eliminated by 4 weeks after sprigging. Nitrogen rate rarely affected the rate of establishment, however, dry weight of stolons/rhizomes decreased as N rate increased. In the management study summer shoot density quadratically increased as N rate increased, to a rate of 7.2 g N m-2 month-1, and decreased thereafter. Mowing height affected clipping yield; but little else, including resistance to tearing.