Effects of the Baldree Traffic Simulator On the Wear Tolerance of Four Bermudagrass Hybrids.

The Cady Traffic Simulator is a modified core cultivation unit capable of simulating three-directional dynamic force.  However, the cleated feet on the Cady were constructed using a looped truck tire, which lacks durability resulting in inconsistent wear and frequent repair.  Therefore, there is a need for a traffic simulator capable of creating dynamic force with improved durability.  It would also be advantageous to explore the effect of hybrid bermudagrass (Cynodon dactylon x C. transvalensis) morphological characteristics on wear tolerance.  The objectives of this research were to first, evaluate the bio-physiological effects of a novel traffic simulator, with improved durability, on a native soil turfgrass system.  Secondly, evaluate the wear tolerance of four hybrid bermudagrass genotypes.  This research was conducted at the University of Georgia Costal Plains Experiment Station, Tifton, GA.  Experimental design was a randomized complete strip-block design with three replications.  Factors included bermudagrass hybrids, weekly traffic rates and location.  Bermudagrass hybrids included ‘Tifway' and ‘TifSport', as well as two experimental varieties 04-76 and DT-1.  Simulated traffic was applied using the Baldree Traffic Simulator over a 6-week period, at rates of 4 passes per week, 2 passes per week and a control, which did not receive traffic.  The Baldree traffic simulator is a modified Ryan GA 30, with fabricated, spring loaded steel plate feet studded with screw in cleats.  Traffic was applied to location 1 from March 23 to April 27, 2012 and to location 2 from April 27 to June 1, 2012.  After six weeks of traffic, DT-1 had the greatest turfgrass density followed by Tifway, then TifSport, and finally 04-76.  Traffic applied once and twice weekly increased soil bulk density, but only the twice weekly application inhibited root recovery.  Initial dark green color index, leaf length, percent green cover and turf quality were correlated to turfgrass wear tolerance.