Research on the multi-year effects of foliar and granular nitrogen fertilizers alone or in combination on turfgrass tissue and soil nutrient concentrations is limited. The research objective was to determine the effect of different foliar and granular nitrogen fertilizers on Penn `A-4' creeping bentgrass (Agrostis palustris Huds.) grown on three putting green rootzones. The fertilizer treatments were urea, methylene urea, natural organic, foliar alone, foliar + granular, and an untreated control. The three rootzones were a United States Golf Association specification rootzone (80:20, v:v), sand/peat/soil rootzone (80-10-10, v:v:v) and a sandy clay loam. The urea, methylene urea, and natural organic fertilizer treatments were applied at 24.4 kg N ha-1month-1. The foliar treatment was applied at two rates, 12.2 kg N ha-1month-1 and 24.4 kg N ha-1month-1. Soil and tissue samples were collected in October 2009, June 2010, October 2010, June 2011, and October 2011. Turfgrass color, quality and chlorophyll ratings were measured weekly for 2009 - 2011. Ball roll distance was measured in July and August in 2010 and 2011 using a Pelzmeter. Dollar spot (Sclerotinia homeocarpa) and worm casting mounds were counted throughout the season when present. Results indicate that higher soil N, P, and K values did not result in higher tissue N, P, and K values among rootzones. Granular fertilizers had better color and quality in the late fall and faster green up in the spring. Foliar applications result in better turfgrass color and quality under summer stress. The natural organic treatment had the shortest ball roll distance, and the largest percentage of annual bluegrass invasion.
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