Late Fall and Winter Nitrogen Fertilization of Turfgrass in Two Pacific Northwest Climates

Abstract

<jats:p>Late fall N fertilization of cool-season turfgrass in northern climates is a common practice. Previous research has been focused in climates where freezing temperatures prevail. Research in more moderate northern climates where turf may not go through winter dormancy is scarce. Four fertilizer N sources and an untreated control were applied in four different months (November, December, January, or February) to perennial ryegrass (<jats:italic>Lolium perenne</jats:italic> L.) in Puyallup, Wash., and to kentucky bluegrass (<jats:italic>Poa pratensis</jats:italic> L.) In Pullman, Wash., to compare their effects in moderate (Puyallup) and freezing (Pullman) winter climates. In Pullman, only November applications of ammonium sulfate (AmS) or polymer coated sulfur coated urea (PCSCU) enhanced winter turfgrass quality. In Puyallup, November or December application of AmS, PCSCU, or polymer coated urea (PCU) resulted in enhanced winter quality. Polymer coated urea yielded a delayed initial response and a longer residual effect in the spring. Isobutylidenediurea (IBDU) did not improve winter turf quality in either Pullman or Puyallup. Although there was no quality response following January fertilizer application, there was suppression of red thread [<jats:italic>Laetisaria fuciformis</jats:italic> (McAlpine) Burds.] symptoms in Puyallup, indicating N uptake. Late fall fertilizer N in eastern Washington should be confined to November, using soluble or more quickly available slow-release nitrogen fertilizers. The application window can be extended to December in western Washington, and more slowly available coated ureas can be effectively used.</jats:p>

Effects of Low Temperatures on Nitrogen Uptake, Partitioning, and Use in Creeping Bentgrass Putting Greens

“…Results from this study demonstrate the quality and color benefits of late‐fall N applications on creeping bentgrass putting greens, supporting the findings cited in other research for northern environments (Powell et al, 1967b; Wilkinson and Duff, 1972; Ledeboer and Skogley, 1973, Wehner et al, 1988; Wehner and Haley, 1993; Miltner et al, 2004; Grossi et al, 2005; Mangiafico and Guillard, 2006; Bigelow et al, 2007). Ammonium sulfate applications from the end of September to mid‐October, with soil temperatures near 10°C, were effective in producing positive turfgrass quality and color responses in the fall; higher rates (up to 50 kg N ha −1 ) increased these effects.…”

“…Efficient fertilizer N use has been the goal of turfgrass researchers for many years (Hull and Liu, 2005). In northern climates, late‐fall N fertilization of cool‐season turfgrasses is a widely accepted practice (Miltner et al, 2004), with recommended rates ranging from 25 to 49 kg N ha −1 for creeping bentgrass putting greens, depending on N source (Kussow, 1988). The recommended timing for this application is just after turfgrass shoot growth ceases due to low air temperatures (Wilkinson and Duff, 1972; Kussow, 1988), while the roots are still able to absorb nutrients (Snow, 1982; Landschoot, 2010).…”

“…The recommended timing for this application is just after turfgrass shoot growth ceases due to low air temperatures (Wilkinson and Duff, 1972; Kussow, 1988), while the roots are still able to absorb nutrients (Snow, 1982; Landschoot, 2010). Soluble N sources, such as urea or ammonium sulfate, which are readily plant available, are commonly used for this application (Miltner et al, 2004; Koski and Street, 2010). Reported benefits of late‐fall N fertilization include improved fall and/or early spring color or quality (Powell et al, 1967b;Wilkinson and Duff, 1972; Ledeboer and Skogley, 1973; Wehner et al, 1988; Wehner and Haley, 1993; Miltner et al, 2004; Grossi et al, 2005; Mangiafico and Guillard, 2006; Bigelow et al, 2007), increased rooting (Hanson and Juska, 1961; Powell et al, 1967a; Moore et al, 1996), and an increase in carbohydrates (Schmidt and Shoulders, 1971).…”

Single Fall Applications of Coated Urea Fertilizers Produce a High Quality Kentucky Bluegrass Turf

“…Other specialists have suggested three consecutive N applications spanning September through November (7). These late-season water soluble N applications have received increasing scrutiny for their potential to negatively affect water quality due to N leaching (4,5,6,8,9,10,21,23,24,27). Compared to commercial lawn care services, most homeowners are not committed to regular fertilization, resulting in malnourished, low density, weed-and disease-prone lawns primarily due to insufficient N. An additional challenge that homeowners encounter is product availability during mid to late fall because many large warehouse-type garden centers replace fertilizers with holiday decorations starting in early October.…”

Retention of surface nitrate additions in a temperate old field: implications for atmospheric nitrogen deposition over winter and plant nitrogen availability

“…In addition, while plant uptake can reduce leaching in the fall, trace gas losses of nitrogen from leaf litter can be high over winter (Dejoux et al 2000), and there can be poor synchronization of the mineralization of crop residues with the timing of uptake by the subsequent crop (Catt et al 1998). Even in forage and turf grass systems, where the same crop is continuously present, little of the nitrogen fertilizer applied in late fall or winter may be taken up by plants (Miltner et al 2004), although microbial immobilization of nitrogen from fertilizer or plant residues can be high in these systems when plant uptake is low (Blankenau et al 2000).…”