Fertilizer Source Affects Nutrient Losses from Hybrid Bermudagrass during Surface Runoff

Abstract

<jats:p>Controlled-release fertilizers (CRFs) provide an extended period of nutrient availability for turfgrass growth and may limit offsite nutrient losses compared with water-soluble fertilizers (WSFs). However, increasing temperatures and soil moisture accelerate nutrient release from many CRFs. As a result, turfgrass managers growing turfgrass in warm, humid climates with high rainfall question how effective CRFs are in reducing nutrient runoff losses while maintaining aesthetic quality. A study was conducted to examine the effect of three fertilizer treatments—an unfertilized control, a CRF applied at 87 lb/acre nitrogen (N), and a WSF applied at 87 lb/acre N as a split application (43.5 lb/acre N) at 0 and 45 d after initial fertilization (DAIF)—on nutrient losses from ‘Tifway’ hybrid bermudagrass (<jats:italic>Cynodon dactylon</jats:italic> × <jats:italic>C. transvaalensis</jats:italic>) during surface runoff events. Rainfall simulations were conducted 3, 28, 56, and 84 DAIF at an intensity of 3 inches per hour to induce 30 minutes of runoff. Water samples were analyzed for inorganic N and dissolved total phosphorus (DTP). Hybrid bermudagrass quality was similar among fertilizer treatments with CRF application, resulting in slightly higher quality. Across all fertilizer treatments, hybrid bermudagrass exhibited similar runoff initiation time and volumes within each rainfall simulation event. Nutrient losses from fertilized hybrid bermudagrass were greatest at the first runoff event at 3 DAIF, with WSF having the greatest losses. The subsequent application of WSF 45 DAIF did not result in greater N and DTP losses compared with CRF application, most likely a result of water incorporation applied to prevent wilting. Hybrid bermudagrass fertilized with a single application of CRF resulted in 23.6% and 55.6% reductions in cumulative inorganic N and DTP losses, respectively, compared with hybrid bermudagrass fertilized with the a split application of WSF.</jats:p>

Plant‐available soil nitrogen fluxes and turfgrass quality of Kentucky bluegrass fertilized with humic substances

“…by 24-56%, thus reducing ground and surface water contamination (Engelsjord & Singh, 1997;Guillard & Kopp, 2004;Sanders & Beasley, 2019). Ion exchange membranes (IEM) and mesh bag techniques have been used to determine the amount of plant-available N and the N release (NR) rate from EEFs.…”

“…Additionally, EEFs can decrease NO 3 -N concentration in leachate by 62-93% and nutrient losses from runoff by 24-56%, thus reducing ground and surface water contamination (Engelsjord & Singh, 1997;Guillard & Kopp, 2004;Sanders & Beasley, 2019).…”

“…Furthermore, EEFs also decreased NH 3 emissions by 41–72% compared with conventional fertilizers (Huckaby et al., 2012; LeMonte et al., 2016; Schlossberg et al., 2018). Additionally, EEFs can decrease NO 3 ‐N concentration in leachate by 62–93% and nutrient losses from runoff by 24–56%, thus reducing ground and surface water contamination (Engelsjord & Singh, 1997; Guillard & Kopp, 2004; Sanders & Beasley, 2019).…”

Modeling NO3–N leaching during establishment of turfgrasses irrigated with tailored reclaimed water

“…Numerous studies have documented factors influencing NO 3 –N leaching from turfgrass areas. These factors include management practices such as rate of N application (Easton & Petrovic, 2004; Frank et al., 2006; Trenholm et al., 2012), N fertilizer source and timing of application (Guillard & Kopp, 2004; Saha et al., 2007; Sanders & Beasley, 2019; Telenko et al., 2015), irrigation management (Morton et al., 1988; Starrett et al., 1995; Trenholm et al. 2012), clipping management (Kopp & Guillard, 2005, 2009), and type of aerification (Nektarios et al., 2014).…”

“…management practices such as rate of N application (Easton & Petrovic, 2004;Frank et al, 2006;Trenholm et al, 2012), N fertilizer source and timing of application (Guillard & Kopp, 2004;Saha et al, 2007;Sanders & Beasley, 2019;Telenko et al, 2015), irrigation management (Morton et al, 1988;Starrett et al, 1995;Trenholm et al 2012), clipping management (Kopp & Guillard, 2005, 2009, and type of aerification (Nektarios et al, 2014). Other factors that influence leaching include soil texture or characteristics (Barton & Colmer, 2006;Petrovic, 1990), turfgrass genotype (Bowman et al, 1998(Bowman et al, , 2002Liu et al, 1997), and method of establishment (i.e., seeding vs. sodding; Geron et al, 1993).…”