Abstract
Best management practices have been developed for lawn care in Florida to minimize any potential adverse impacts from lawn care activities. The objectives of this study were to evaluate the effect of nitrogen rates and mowing heights on nitrate leaching and turf quality of St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze.]. The experiment was conducted in a greenhouse at the University of Florida in Gainesville. Nitrogen was applied as urea (46–0–0) at the rate of 2.5, 4.9, 7.4 and 9.8 g·m–2 N every 2 months. Mowing height treatments were 7.6 and 10.2 cm. Experimental design was a randomized complete block with four replications. In the first two treatment cycles, there were no differences in nitrate leaching due to N rate. Percentage of applied nitrogen leached was less than 1% throughout the study at all rates. Averaged over the course of the study, greater leaching occurred at the lower mowing height. Turf visual quality and color scores increased with nitrogen rate, but were at acceptable levels at all rates. Root weights were significantly increased at the higher mowing height. From results of this research, it does not appear that application of nitrogen at these rates will result in greater than 1% of applied N being leached from St. Augustinegrass, particularly when the grass is maintained in a healthy condition.