A comparison of visual vs. instrumental measurement of color differences in bentgrass turf

This study was conducted to determine: 1) if the Minolta CR-310 Chroma Meter can detect color differences among bentgrass (Agrostis stolonifera L., A. capillaris L.) cultivars maintained as a turf; 2) how the CR-310 parameters of hue angle, lightness, and chroma compare with visual color assessments; and 3) if the CR-310 can provide consistent color measurements among evaluators. Differences were detected among cultivars with respect to hue angle, lightness, and chroma. Hue angle and chroma were significantly correlated with visual color assessments when data were averaged across all evaluators. Lightness was not strongly associated with visual color assessment. Differences were found among evaluators for visual color assessment, lightness, and chroma, but not for hue angle measurements. Thus, hue angle appears to be the most consistent CR-310 parameter for measuring color of bentgrass turf. These results indicate that the CR-310 can be used to evaluate the color of bentgrass cultivars maintained as a turf and provides consistent hue angle measurements among evaluators, regardless of experience in rating turf color. The CR-310 is probably best used for measuring relative color differences and may be useful if cultivars of similar color are desired in blended turfs.