The Impact of Pre-Plant Phosphorus and Potassium on Turf Type Tall Fescue Establishment.
Glenn Hardebeck1, Cale Bigelow1, Kristina Walker1, and Doug Smith2. (1) Purdue University, 915 West State Street, West Lafayette, IN 47907, (2) USDA-ARS National Soil Erosion Research Laboratory, 275 South Russell Street, West Lafayette, IN 47907-2077
The application of starter fertilizers containing elevated phosphorus (P) and potassium (K) has long been prescribed when establishing turfgrasses, regardless of existing soil nutrient status. Increased public concern regarding nutrient losses to the environment has brought many traditional fertilization practices into question. The objective of this two-year field study was to determine the effect of varying pre-plant P and K levels when incorporated into the upper 2.5 cm, on the establishment of turf-type tall fescue (Festuca arundinacea Schreb. ‘Quest') when seeded on three dates at two locations with varying inherent P (35 vs. 150 ppm) and K (220 vs. 375 ppm) levels. Main plots were seeding date (Aug., Sept. and Oct.) and sub-plots were P rate (0, 49, and 98 kg ha-1) in combination with K rate (0 and 49 kg ha-1), with 49 kg N ha-1 also added. Establishment was measured as percentage turf cover and initial spring clipping yields. As expected, tall fescue established most rapidly when seeded in Aug. or Sept. and slowest when seeded in Oct.. Furthermore, winter-kill, measured as a significant decline in cover, was documented for the Oct. seeding at both locations. In year one, at the lower P and K fertility location, 98 kg P ha-1 increased April turf cover by 21% over plots receiving no P (35 % cover) within the Sept. seeding date. Turf cover trends were similar for the Oct. seeding date at that location. Additionally, spring clipping yield (884 kg ha-1) increased for the high P rate treatment within the August seeding date compared to plots receiving no P, 555 kg ha-1. Therefore, incorporating P at seeding should continue to be a recommended practice because it improves establishment and aids in winter survival especially on soils with medium to low P levels.