RT Journal Article SR Electronic T1 Management effects on nitrogen leaching and guidelines for a nitrogen leaching index in New York JF Journal of Soil and Water Conservation FD Soil and Water Conservation Society SP 499 OP 504 VO 57 IS 6 A1 H. M. van Es A1 K. J. Czymmek A1 Q. M. Ketterings YR 2002 UL http://www.jswconline.org/content/57/6/499.abstract AB Management practices may affect the potential for nitrate leaching from agricultural systems. Two studies are discussed that used plot-size lysimeters on loamy sand and clay loam soil in Northern New York. One was conducted from 1991 to 1994 and involved sod plowing and the use of three rates of fertilizer on maize (Zea mays L). The other study was conducted from 1997 to 2000 and quantified N-leaching losses under maize and orchardgrass (Dactylis glomerata L.) as affected by the timing of manure application. These studies showed that timing and rate of N fertilizer and manure additions, timing of green-manure incorporation, and soil type strongly influenced N-leaching losses. Losses from fall-applied N sources were high, especially on coarse-textured soils. Lower N losses in fine-textured soils were primarily the result of higher denitrification losses, rather than reduced percolation rates. It was concluded that the current N Leaching Index ignores important processes and requires a more dynamic approach that includes management factors. In the interim, we established a set of best management practices for N to reduce the potential for N leaching losses.