100657 Tall Fescue Lawn Turf Response to Various Phosphorus Containing Fertilizers.
Poster Number 336-1216
See more from this Division: C05 Turfgrass Science
See more from this Session: Turf Ecology and Management Poster (includes student competition)
Tuesday, November 8, 2016
Phoenix Convention Center North, Exhibit Hall CDE
Abstract:
Lawns fertilized with excess nitrogen (N) and phosphorus (P) may be an important possible contributor to declining water quality throughout the USA. This concern has led some states to ban P-fertilizer applications to turf. The long-term effects of eliminating P from lawn fertilizer programs on turf health and soil test P levels is unclear. A five-year field study evaluated the effects of six granular fertilizers consisting of synthetic and natural organic products with varying N:P ratios and an unfertilized control. Fertilizer was applied at 196 kg N ha-1 yr-1 to a turf-type tall fescue (TTTF) grown a calcareous silt-loam (initial Bray-1 soil test P, STP, = 33 ppm). Clipping management strategy (returned or removed) was also studied. Soil and leaf tissue were sampled to monitor P levels and visual appearance, green color and shoot density were also assessed. Turf receiving N-fertilizer, regardless of the N:P ratio, was superior to the unfertilized controls, which had poor vigor and a decreased shoot density. By year 3, mean STP levels ranged 36-79 ppm and fertilizers with N:P ratios of 1:1 or 3:1 caused substantial STP increases, > 60 ppm, regardless of clipping management strategy. This study indicates that where initial STP levels are sufficient, a healthy TTTF can be produced using N only fertilizers at this annual N-rate. Continued application of lawn fertilizers with N:P ratios of < 3:1 could eventually result in excess P loading and environmental loss.
See more from this Division: C05 Turfgrass Science
See more from this Session: Turf Ecology and Management Poster (includes student competition)