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Table 70. N sources and manufacturers. Code I Description %N Manufacturer KUREranularurea46 PCS Sales, Inc.Northbrook, IL :30 urea:xcu 45 ws a slud e bio-solid 5 Milor anite,Milwaukee, WI f mer coated urea 41 Pursell Inc., S lacau a,AL f mer coated urea 43 A rium Advanced Technologies, AL RESULTS Turfgrass Quality,Color and Clipping Growth Turfgrass quality was significantly affected by fertilizer treatment on most observation dates and the readily soluble N treatments generally had the quickest response with some slow and controlled release N forms providing better turfgrass quality over timeframe within the blackout period and then after that period (Tables 2a-2b). In the no-N check,turfgrass quality dipped below the 6.0 minimally acceptable rating on 6/25 and was consistently the lowest rated treatment(Tables 2a-2b). Turfgrass color ratings had similar treatment responses (Tables 3a-3b). Turfgrass clipping growth responded to the application of the various forms of N as anticipated by the availability of N from the N sources (Tables 4a-4b). The controlled release source PCU had the most clippings at the end of the reporting period while having the least early on (Tables 4a-4b). N Leaching and Climatological Data The trial was conducted during the rainy season months encompassing blackout period months. Thus, nearly 100 cm of rain and irrigation impacted the site during the trial months and June and July each had approximately 25 cm of rain (Figure 18). Nitrate-N leaching was significantly-affected by N treatment with the urea treatment having the most cumulative leaching followed by the 70:30 soluble/slow combination treatment and other treatments (Table 74a-e, Figure 19). The 3 slow or controlled release N products had Nitrate-N leaching totals that were statistically—equal to the no-N check,were lower than the urea treatment, and statistically-equal to the 70:30 combination treatment(Tables 74a-e). Most of the leaching occurred during the first month after application(Table 74a). Thereafter,there were no significant differences in leaching. In conclusion,while the application of N at a high rate to compensate for black out restrictions improved visual ratings and growth,there was increased N leaching from turf receiving readily-available N. Using complete slow or controlled-release N reduced N leaching to statistically-equal amounts achieved the no- N check and improved turfgrass visual ratings and growth at the end of the study. 89