Effect of Sunlight, Temperature, and Relative Humidity on Putting Green Health in Chicago.
Douglas Kieffer, Spectrum Technologies, Spectrum Technologies, 12360 S. Industrial Dr. East, Plainfield, IL 60585 and Derek Settle, Chicago District Golf Assoc., Chicago District Golf Association, 11855 Archer Avenue, Lemont, IL 60439.
Light is essential for maintaining healthy turfgrass. However, landscape features can lead to light deficiencies on golf courses, especially on greens. During July and August of 2007, air temperature, soil temperature, relative humidity and photosynthetically active radiation (PAR) were measured at 15-minute intervals on putting greens of 15 Chicago area golf courses. The transition period between July and August was selected to capture the historical period of physiological decline of golf greens in Chicago, IL. At each course, the superintendent allowed the deployment of a mini-weather station, mounted 1 ft high, on the green collar edge. Whenever possible, a shaded location was selected. Plant health was assessed by visual quality ratings and normalized difference vegetative index (NDVI). Measurements were averaged from three 6 ft X 6 ft sub-plots taken on green height turf nearest the weather station. Composition of turfgrass species (creeping bentgrass:Poa annua) on each green was estimated at study start. Statistical analysis was performed to identify correlations between measured environmental data and turf health indicators of visual quality and NDVI.