Effects of Composted Municipal Biosolids and Nitrogen on Turfgrass Establishment.
Ronnie Schnell1, Donald Vietor2, Richard White2, and Clyde Munster2. (1) Texas A&M University, 1138 Private Road 4482, Giddings, TX 78942, United States of America, (2) Soil & Crop Sciences Dept, Texas A&M University, Texas A&M University, College Station, TX 77843-2474, United States of America
Cycling composted municipal biosolids (CMB) through turfgrass sod production can enhance the rate of turf establishment. Compost amendments provide organic carbon and nutrients and improve soil water retention and turf growth on low quality soils. Nitrogen (N) fertilizer can enhance turf growth depending on the ability of CMB to supply N. The purpose of this research is to quantify the effects of CMB and N on establishment of Tifway bermudagrass. A factorial arrangement of three N rates with and without CMB was replicated four times. The CMB was incorporated to make up 25% by volume of soil in three amended treatments. Three remaining treatments comprised soil without CMB. In addition, fertilizer was applied to supply 30 kg P ha-1 and 200 kg K ha-1 to soils without CMB. Three N rates (0, 50 and 100 kg ha-1) were assigned to treatments with and without CMB. All treatments were sprigged with Tifway bermudagrass in October, 2006. Nitrogen fertilizer was applied three weeks after sprigging and after green-up in the spring. Digital photographs were taken throughout the establishment period. The images are analyzed with ImageJ software using the “threshold color” plugin to determine the percentage of green turf in each plot area. ImageJ is a public domain image processing software and is available as a free download or an online applet. Images were cropped to include only plot area in analyses. The threshold color is used to isolate the green or grass portion of the plot. The image is converted to 8-bit and the threshold is adjusted to include the colors of interest. The image is digitally analyzed to report the percentage coverage of turfgrass compared to the entire plot. Univariate analysis of variance is performed with SPSS 13.0 to compare treatments.