Visual turfgrass evaluation has been used for rating turf color, density, and turfgrass quality for many years. Horst et al. (1984) found that visual assessment required less time, and less money than alternative means of assessment. However, they also found that visual assessments were inconsistent among 10 evaluators. Also, assessing visual turfgrass quality is often subjective and time consuming (Trenholm et al., 1999, Bell et al., 2002). In addition, visual evaluators may be distracted by mowing patterns, rating direction, cloudiness, shadows, and turf wetness. These distractions sometimes make it difficult for evaluators to determine turf responses or genetic variation. Recently optical sensing techniques have been introduced to measure the reflectance from turf canopies to determine turfgrass growth (Bell et al., 2004) wear tolerance (Trenholm et al., 1999), herbicide tolerance (Bell ea al, 2000), and N fertility(Bell et al., 2002a). This study was conducted at Oklahoma State University Turfgrass Research Center in Stillwater, OK. Visual ratings and optical sensing measurements were collected on the schedule prescribed by the National Turfgrass Evaluation Program (NTEP) for 4 NTEP studies.