Corn Yields with Fall, Spring, and Sidedress Nitrogen¹

Abstract

Studies in central and northern Illinois at 4 locations and 12 location‐years were conducted with 5 rates of N applied in the fall and as spring‐preplant. Sidedress N was also included at 1 of the 4 locations for 4 years. Relative efficiency of the times of application was calculated by dividing the corn (Zea mays L.) yield increase from a given rate of N added at one time by the yield increase from the same rate of N applied at another time. At the Carthage and Hartsburg locations the 3‐year average relative efficiencies of fall‐ versus spring‐applied N are about 0.8 and 0.9 (fall was 80 and 90% as effective as spring) at N rates of 67 and 134 kg/ha, respectively. Fall and spring N were about equally effective at 201 and 268 kg/ha of N. There was generally little yield response to N rates greater than 201 kg/ha at Carthage and Hartsburg. Fall and spring N gave similar corn yields for all rates of N at Urbana. For the 4‐year average at DeKalb, sidedress N was the most effective, spring N was intermediate, and fall‐applied N was the least effective. The difference between spring and sidedress N was less than that between fall and spring N. There was considerable year‐to‐year variation in relative efficiency. The importance of the time at which conditions suitable for N loss occur is discussed.

Current Nitrogen Management Status and Measures to Improve the Intensive Wheat–Maize System in China

“…Therefore, more N fertilizer (around 60-70% of the total N fertilizer applied) should be applied during the fastest growing stages of the crop to achieve synchrony between the N supply and crop demand. This is consistent with early observations that N fertilizer should be applied close to the peak N uptake to increase grain yield and NUE and decrease the opportunity for soil N losses (Russelle et al 1981;Welch et al 1971).…”

“…Nitrogen application in excess of crop N demand at the early growth stage increases the potential for nitrate-N leaching and results in excessive crop growth that is more susceptible to disease infection and wheat lodging. Applying N fertilizer near to the time it is needed by the crop increases crop grain yield and improves NUE (Russelle et al 1981;Welch et al 1971). Results from Iowa (Sanchez and Blackmer 1988) indicate that 50-64% of fall-applied N is lost from the upper 1.5 m of soil by processes other than crop uptake.…”

Responsive in-season nitrogen management for cereals

“…Efficiency of use from a single pre-plant N-fertilizer application typically decreases in proportion to the amount of N fertilizer applied (Reddy and Reddy, 1993). Other studies have substantiated that in-season applied N resulted in a higher NUE than when N is pre-plant applied (Miller et al, 1975;Olson et al, 1986;Welch et al, 1971;Randall et al, 2003a,b). Collectively, these results agree with the recommendations of Keeney (1982), who advocated that the most logical approach to increasing NUE is to supply N as it is needed by the crop.…”

Navigating the Socio-Bio-Geo-Chemistry and Engineering of Nitrogen Management in Two Illinois Tile-Drained Watersheds

“…It is not surprising that tile nitrate yields were greater from the C-C system than the C-S system because no fertilizer was applied during the soybean year in C-S in 2011. However, numerous studies have shown that fall and winter applications of fertilizer N can lead to increased tile nitrate losses compared with spring applications (Welch et al, 1971;Frye, 1977;Gentry et al, 1998;Randall et al, 2003;Clover, 2005). After corn in 2010, nitrate concentration in both tiles tracked one another until a large precipitation and tile flow event on 16 Feb. 2011.…”