Fig. 1. Clipping N concentration measured at each 20-d period for `Tifgreen' bermudagrass under three N sources (Hydroform, HYD; sulfur-coated urea, SCU; and urea, URE), two N rates (100 and 200 kg ha^-1), and two fertilization frequencies (every 20 and 40 d). Arrows represent time of N application. Each point represents the average of three observations. Vertical bars represent LSD₀₅ for (a) treatments across periods and (b) treatments at the same or different period for both frequencies in each experiment