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Agronomy Journa l • Volume 110 , I s sue 6 • 2018 Lawns and turfgrass areas represent the largest irrigated crop in the United States, accounting for approximately 163,800 km2 (±35,850 km2) (Milesi et al., 2005; Morris et al., 2005). These areas provide benefits such as the reduction of heat island effects, soil erosion control, carbon sequestration, cool and safe surfaces for exercise and athletic activities, to name a few (Beard and Green, 1994; Leinauer et al., 2010; Wang et al.; 2016). In addition to the aforementioned environmental benefits, the turfgrass industry contributes billions of dollars annually to the United States economy (Haydu et al., 2008). However, despite these advantages, as a non-food and fiber producing crop, turfgrass water usage is a major concern in many communities. For this reason, multi-pronged approaches to conserve irrigation water, such as the use of alternative water sources, the use of efficient irrigation systems, applying deficit irrigation, and the use of warm-season grasses have been investigated and recommended in recent years (Leinauer and Devitt, 2013). Deficit irrigation is defined as the application of water below full crop water requirements (evapotranspiration [ET]) and has become a widely adopted strategy to conserve irrigation water (Fereres and Soriano, 2007; Leinauer et al., 2010). Deficit irrigation aims to use the minimum amount of water needed to provide and maintain acceptable turfgrass quality (Gibeault et al., 1985). Such an approach exposes turfgrasses to chronic stress, and recovery usually only occurs following periods of sufficient rainfall. Several studies have investigated quality of various turfgrass species during such imposed drought, and the general consensus is that warm-season grasses are better adapted to sustain longer periods of deficit irrigation than cool-season grasses (Chalmers et al., 2008; Sevostianova et al., 2011). Bermudagrass [Cynodon dactylon (L.) Pers.] represents one of the most widely used warm-season turfgrasses in arid and semiarid climate zones because it requires significantly less water than cool-season grasses, is traffic tolerant, and can be maintained at all mowing heights needed for turf areas (Hanna et al., 2013). Published evapotranspiration rates for bermudagrass range from Combining Trinexapac-Ethyl with a Soil Surfactant Reduces Bermudagrass Irrigation Requirements