Mineral composition of Kentucky bluegrass under effluent water irrigation
Effects of three types of water were studied at eight Colorado golf courses.
Photo by Yaling Qian
Research was conducted on Kentucky bluegrass at eight Colorado golf courses irrigated with three types of water: three courses in Denver after 10 years of effluent water irrigation; three courses in nearby cities after 10+ years of effluent water irrigation; and two courses receiving surface water for irrigation.
Soil pH, EC, organic matter, calcium, magnesium, potassium, sodium, boron and sodium adsorption ratio (SAR) of soil saturated paste were determined. Kentucky bluegrass shoots were sampled from 25 roughs and analyzed for mineral concentration (sodium, calcium, magnesium, potassium, boron, chlorine, sulfur, phosphorus, manganese, iron, zinc, copper and molybdenum).
Ten years or more of effluent water irrigation increased sodium content of clippings 4.3 to 9.9 times, chloride content 1.5 to 1.3 times, and boron 1.3 to 3.5 times. In contrast, effluent irrigation reduced the potassium:sodium ratio by 74% to 90%.
Mathematical analysis was conducted to identify the relationships between mineral concentration in clippings and turf quality, and found that sodium was the only element that strongly and negatively influenced turf quality. There was a linear relationship between turf quality and sodium content in the clippings, and soil SAR at a depth of 0 to 20 cm was highly associated with Kentucky bluegrass shoot sodium content.
— Yuhung Lin and Yaling Qian, Ph.D., Colorado State University, Fort Collins
Editor’s note: An earlier version of this summary was published in the 2016 ASA-CSSA-SSSA Meeting Abstracts, ASA, CSSA and SSSA, Madison, Wis.
Teresa Carson is GCM’s science editor.