Department of Plant Sciences

Liquid applications of nutrients to turfgrass are a routine management practice. A better understanding of nutrient chelating chemistry coupled with a measurable increase in products marketed to turfgrass professionals purported to facilitate effective and efficient absorption of nutrients into turfgrass leaves has resulted in a need for a better understanding of the capacity of turfgrass species to absorb essential nutrient elements. Research was conducted with the objectives to 1) determine the foliar uptake of nutrients in solution to Creeping Bentgrass (Agrostis palustris Huds.), Annual Bluegrass (Poa annua var. reptans (Hausskn.) Timm) and Ultra-Dwarf Bermudagrass (Cynodon dactylon x C. transvaalensis Burtt-Davy).and 2) determine temporal, location and seasonal differences in foliar uptake among these same species. Based on the results of this study it was found that foliar uptake was significantly affected by source of nutrient with organic chelating agent, when differences were identified, facilitating greater uptake vs. synthetic (i.e. EDTA) chelation. Time of year affected absorption efficiency with cooler temperature resulting in lower uptake. This is speculated to be highly influenced by ambient temperatures at time of application. Volatility losses were not measured in this study so caution should be exercised for interpretation of nitrogen results, especially NH4. The species investigated exhibited appreciable uptake of nutrients applied in solution. Liquid applications and more specifically, organically chelated foliar products, could reduce total nutrient applications and decrease potential for surface and ground water contamination due to decreased migration of select nutrients to the root zone.