Considerations with Determining the Minimum Number of Volumetric Water Content Measurements for Turfgrass Root Zones

Water is considered the most important natural resource utilized on managed amenity grasslands, and water conservation is an integral part of an overall program in environmental stewardship and best management practices. Measuring and monitoring the soil water content of turfgrass root zones has become an important and routinely accepted practice of golf courses and sports pitches. In recent years, portable hand-held soil moisture meters or sensors have become commercially available and affordable, and therefore have become a valuable and often relied-upon tool for the turfgrass industry practitioner. To maximize or optimize the time and resources needed to measure the root zone volumetric water content of a turf site, a field experiment was conducted to determine the minimum number of soil moisture readings needed per 93 m(2) of a sand-based root zone. Of note, 93 m(2) is equivalent to 1000 ft(2), which is the common form of area measurement utilized by the turfgrass industry in the USA. The standard error of the mean calculated from sampling data revealed that three to four measurements per 93 m(2) were the minimum number required. Soil moisture meters should be utilized in a structured, purposeful, and site-specific manner along with traditional soil moisture evaluation methods of diligent scouting for visual signs of turfgrass wilt and drought stress, as well as examining soil root zone cores, to support prudent irrigation water management practices. Knowledge of the soil moisture status will support best practices for water conservation and environmental stewardship while optimizing turfgrass quality, function, and performance.