Moisture Sensor‐Controlled Irrigation for Maintaining Bermudagrass Turf¹

Abstract

The feasibility of tensiometer soil moistnre sensinK devices for schedolinK bermudagrass (Cynodon dactylon X C. transFaaknsis) torr irription and their impact on N fertilization practices under su~tropical conditions was assessed. Irription water savinp of 42 to 95% were obtained in sensor controUed plots over conventionaUy irripted plots. The Kfeatest benefit of the sensor system was achieved durinK periods of frequent but unpredictable rainfaU by eUminatinK unnecessary irriKations. Application of a wettinK aKent was necessary durinK extended dry periods to prevent localized dry spots when irription was limited by the sensor system to an as needed basis.Reduced irription by the sensor system resulted in better torr appearance and equal effectiveness of water-soluble and slow-release N sources.

A Review of Turfgrass Fertilizer Management Practices: Implications for Urban Water Quality

“…Nitrogen leaching can be minimized by applying water soluble fertilizers frequently at relatively low rates and CRFs less frequently at relatively higher rates (Barton and Colmer, 2006;Engelsjord and Singh, 1997;Snyder et al, 1984). On golf greens in Georgia, water soluble N (potassium nitrate, urea, and ammonium phosphate) resulted in significantly greater NO 3 -N concentrations in leachate than CRFs (poly-and sulfurcoated N) at application rates ranging from 0 to 49 kgÁha -1 N (Shuman, 2001).…”

“…Appropriate fertilization and irrigation management practices for both turfgrass and landscape plants reduce the potential for nutrient runoff and leaching compared with other land uses (Table 2) (Augustin and Snyder, 1984;Easton and Petrovic, 2004;Exner et al, 1991). Gold et al (1990) analyzed NO 3 -N in leachate from multiple land uses in southern New England; both fertilized cornfields (66 kgÁha -1 per year) and septic systems (48 kgÁha -1 per year) had greater leachate NO 3 -N loads than fertilized (6 kgÁha -1 per year) and unfertilized lawns (1.4 kgÁha -1 per year).…”

Sensor-Based Control of Irrigation in Bermudagrass

“…In addition, the timers were set monthly to replace the historical ET-based irrigation schedule recommended by Dukes and Haman (2002). But Floridian homeowners do not usually adjust their irrigation time clock frequently (Baum et al, 2003;Augustin and Snyder, 1984). Therefore, differences in water use volume could have been greater if the timers were set with few or no scheduling variation among months or seasons.…”

“…A wide range of applications to automatically control irrigation events has been investigated in sandy soils. In Florida, switching tensiometers have been studied for agricultural production (Clark et al, 1994;Smajstrla and Locascio, 1994;Muñoz-Carpena et al, 2003;Smajstrla and Koo, 1986), and for maintaining bermudagrass turf (Augustin and Snyder, 1984). However, these investigations suggest that tensiometers require calibration and frequent maintenance, up to twice per week.…”

Soil Moisture Sensor Landscape Irrigation Controllers: A Review of Multi-Study Results and Future Implications

“…Early research carried out in Florida using switching tensiometers connected to irrigation timers resulted in water savings of 42% to 95% over conventionally irrigated bermudagrass turf plots (Augustin and Snyder, 1984). A 1997 study involving 21 residential sites in Colorado was performed using granular matrix sensors.…”