Foliar Nitrogen Uptake Efficiency of Creeping Bentgrass as Affected by Spray Volume, Adjuvants, Tank-Mixing, and Fertilizer Formulation.

Nitrogen is commonly foliarly applied to highly managed turfgrass swards but methods to enhance N-uptake efficiency are not well characterized. Therefore, we instituted studies to determine what factors affect nitrogen uptake through the foliage of creeping bentgrass (Agrostis stolonifera L.) in order to maximize N-uptake efficiency. The effects of spray volume, adjuvants, tank-mixing, and fertilizer formulation were investigated using ¹⁵N labeled labeled fertilizer at Urbana, IL. Nitrogen uptake was monitored over a 24-hour period by extracting total Kjeldahl nitrogen (TKN) from foliage and analyzing it for ¹⁵N enrichment.