Tall fescue (Schedonorus arundinaceus (Schreb.) Dumort.) turfgrass cultivars performance under reduced n fertilization

The identification of minimal N requirements for sustaining turfgrass quality and functionality became necessary to reduce N fertilization inputs and avoid potential environmental impacts in the European Union. A two year study was conducted at Padova University in Legnaro, northeastern Italy to investigate the performance of four tall fescue (Schedonorus arundinaceus (Schreb.) Dumort.) cultivars ('Lexington', 'Rhambler SRP', 'Rhizing star', and 'Thunderstruck') fertilized twice per year at either 75 or 150 kg N ha−1 year−1. Turfgrass was evaluated every two weeks for turfgrass visual quality, percent green cover (PGR) as well as dark green color index (DGCI) through digital image analysis and normalized difference vegetation index (NDVI). 'Rhizing star' was the only cultivar that showed poor adaptation to the environment, achieving acceptable turfgrass quality (6.0 or higher) only during June and July 2019. Turf fertilized at 150 kg N ha−1 year−1 generally showed higher performance than 75 kg N ha−1 year−1, however, the increase in turfgrass quality was mostly negligible and detected only during the winter months. Results suggest that well adapted tall fescue cultivars could be fertilized at 75 kg N ha−1 year−1 in Northern Italy.