Clipping Management and Nitrogen Fertilization of Turfgrass

Abstract

The effect of returning grass clippings on turfgrass growth and quality has not been thoroughly examined. The objective of this research was to determine the effects of returning grass clippings in combination with varying N rates on growth, N utilization, and quality of turfgrass managed as a residential lawn. Two field experiments using a cool‐season turfgrass mixture were arranged as a 2 × 4 factorial in a randomized complete block design with three replicates. Treatments included two clipping management practices (returned or removed) and four N rates (equivalent to 0, 98, 196, and 392 kg N ha−1). Soils at the two sites were a Paxton fine sandy loam (coarse‐loamy, mixed, active, mesic Oxyaquic Dystrudepts) and a variant of a Hinckley gravelly sandy loam (sandy‐skeletal, mixed, mesic Typic Udorthents). Returning clippings was found to increase clipping dry matter yields (DMYs) from 30 to 72%, total N uptake (NUP) from 48 to 60%, N recovery by 62%, and N use efficiency (NUE) from 52 to 71%. Returning grass clippings did not decrease turfgrass quality, and improved it in some plots. We found that N fertilization rates could be reduced 50% or more without decreasing turfgrass quality when clippings were returned. Overall, returning grass clippings was found to improve growth and quality of turfgrass while reducing N fertilization needs.

Growth and Quality Responses of Tall Fescue (Festuca arundinacea Schreb.) to Different Irrigation Levels and Nitrogen Rates

“…Feldhake (1981) stated that the quality of nitrogen-deficient turf has showed to decline more rapidly when subjected to moisture stress compared to adequately fertilized. In general, several studies indicated that the turf colour and quality ratings ranged from 1 to 9, with an acceptable minimum visual quality number of 6 (Kopp and Guillard, 2002;Bilgili and Acikgoz, 2005). In this study, an acceptable turf grass colour and quality were sustained under the N1I2 treatment throughout of the each experimental season.…”

Relating Turfgrass Growth and Quality to Frequently Measured Soil Nitrate

“…) when clippings are returned (Kopp and Guillard, 2002a). Using the mean absolute TCM 500 NDVI meter value across 3 yr at N rates of 10 to 20 kg N ha -1 mo -1 (0.705 for Kentucky bluegrass and 0.670 for tall fescue), the probability of obtaining or exceeding an absolute NDVI value of 0.705 was p = 0.73 at the C-N critical level of 3.8 mg NO 3 -N kg -1 for Kentucky bluegrass (Fig.…”

Nitrogen budgets of urban lawns under three different management regimes in southern California

“…Qian et al (2003) showed with a CENTURY model simulation that clipping return may increase soil sequestration of C and N by 11-59 and 12-78 %, with greater improvements under lower rather than higher fertilization rates (75 vs. 150 kg N ha -1 year -1 ); meanwhile, this practice may reduce the N requirement of lawns from 25-60 % depending on lawn age. Other studies also showed that clipping return, along with appropriate mowing frequencies, may reduce the need for fertilization (Heckman et al 2008;Kopp and Guillard 2002), preserve soil moisture (Harivandi and Gibeault 1999;Hartin and Harivandi 2001), and improve plant N uptake (Kopp and Guillard 2002); however, it might also potentially increase leaching loss of NO 3 -, especially when fertilization was not reduced or irrigation was excessive (Kopp and Guillard 2005). These practices should be further tested in an ecosystem N budget framework.…”