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If Sudan grass is grown again on the adjoining seven acres, the following lbs/ac of N, P and K must be utilized by the crop to achieve maximum production according to Table 4-1 of the Western Fertilizer Handbook: N: 325 lbs/ac x 7 ac= 2,275 lbs N needed P: 125 lbs/ac x 7 ac= 875 lbs of P205 needed K: 475 lbs/ac x 7 ac=3,325 lbs of K20 needed If six months of manure production is incorporated into the 7 acres of cropland and using the theoretical maximum manure production(moisture-reduced) of 23 ft'/day we have: 23 x 180 days=4,140 ft' x 6 lbs/ft'=24,840 lbs_ 2,000 lbs/ton= 12.4 tons. Six months of manure production has been used in the calculations to account for maximum moisture reduction. Using the nutrient analysis of the stacked manure as illustrated above: 52 lbs N/ton x 12.4 tons= 645 lbs N+ 68 lbs/ac NO3 N currently in soil= 713 lbs 40 lbs P/ton x 12.4 tons=496 lbs P205+483 lbs/ac P205 currently in soil=979 lbs 92 lbs K/ton x 12.4 tons= 1,141 lbs K+2,194 lbs/ac K20 currently in soil=3335 lbs Therefore, if the theoretical maximum manure production for six months were used as fertilizer, the following concentrations will exist for each respective nutrient: 2,275 lbs N needed- 713 lbs supplied by manure and existing in soil= 1,562 lbs N deficient 875 lbs P205 needed - 979 lbs supplied by manure and existing in soil= 104 lbs P205 excess 3,325 lbs of K20 needed- 3,335 lbs supplied by manure and existing in soil =balanced ANIMAL PEN SOILS Soil analyses from the respective animal pen soil depths are found on the SOIL ANALYSIS REPORT. The primary constituent of concern is nitrate-nitrogen. Test results reveal very high nitrogen concentrations throughout the soil profile down to 9 ft. The soil textures are predominately a loamy sand with a 9%to 13% clay content. A loam soil stratum with 21%clay content is found at 9 ft. The phenomenon of denitrification occurs at the 12-ft depth where the nitrate-nitrogen concentration is dramatically reduced. At this depth,the capillary fringe was present and the soil was saturated. The scientific literature documents the denitrification process occurs under anaerobic conditions such as those found in saturated soils. This adequately explains the dramatic reduction in nitrate-nitrogen concentration. High nitrogen levels found at the higher elevations are primarily attributable to the poultry layer cages that were once over these soils, and nitrogen contributions from the goats and sheep. There is no hydraulic head from rainfall since the pens are covered and drinking water volume and therefore, spillage is kept to a minimum. Page -6- Valfey Ag Research