Response of Twenty-Five Warm-Season Turfgrasses to Sixty-Day Drought: Canopy Heat Accumulation and Capacity for Post-Drought Recovery.
Kurt Steinke, David Chalmers, James Thomas, and Richard White. Heep Center 370 Olsen Blvd. 2474 TAMU, Texas A&M University - Soil & Crop Sciences, Texas A&M University, Dept. of Soil & Crop Sciences, College Station, TX 77843
The inability to maintain green ground cover during droughty periods has caused municipalities and water districts to reconsider turfgrass species and cultivar selections available for home consumer use. These recommendations are drafted with little scientific information regarding turfgrass drought tolerance mechanisms or how varieties perform once water is no longer limiting. A study was conducted examining the 60-day drought tolerance of four turfgrass species and 25 cultivars grown over two root zone depths. Canopy temperatures were monitored weekly during the 60-day drought period. Four-inch plugs were removed at 0, 20, 40, and 60 days during the drought period to monitor aggressiveness and recovery of individual cultivars before, during, and after the induced drought. Preliminary data demonstrate that root zone depth had a significant effect (P < 0.05) on turf canopy temperatures and turf vitality. Zoysiagrass canopies appeared to exhibit an earlier expression of dormancy thus impacting turf color, uniformity, leaf firing, and heat accumulation. Bermudagrass cultivars appeared to recover significantly more quickly than the other turf species at zero and twenty days into the drought period. However some species and varieties experienced similarly slow growth rates before and after the droughty period indicating that significant plant recovery following drought conditions may not be possible due to an inherently slow growth rate.