Corn yield and nitrogen uptake in sandy soils amended with municipal solid waste compost

First year and residual effects of municipal solid waste (MSW) compost application on corn (Zea mays L.) grain yield were evaluated on a Verndale sandy loam (coarse-loamy, mixed, Udic Argiboroll) at Staples, MN, and on a Hubbard loamy sand (sandy, mixed, Udorthentic Haplaboroll) at Becker, MN. At both locations, compost 'A' was applied at 0, 20, 40, and 80 dry tons/acre in 1992, and two other composts, 'B' at Staples and 'C' at Becker, were applied at 40 tons/acre in the same year. The N fertilizer treatments were 0 or 220 lb N/acre applied each growing year. With the low C:N ratio mature composts 'B' and 'C', yield was equal to or greater than that of the nonamended control at 220 lb N/acre during the first growing season. Based on the difference between N uptake due to compost and N uptake in nonamended control, about 8% of the total compost N was available from the low C:N ratio composts 'B' and 'C' the first year while compost 'A', which had a high C:N ratio, reduced stand count and induced N immobilization at Staples. At Becker, there was no response in grain yield with compost 'A' without N fertilizer in the first year, however, there was a negative response in grain yield with compost 'A' when N fertilizer was applied. In residual years, grain yield with all composts was greater than or equal to that of the nonamended control without N fertilizer. Nitrogen availability from compost 2 to 3 yr after application ranged from 3 to 10% of the total compost N per year and depended on the rate of compost application. The first year, fall soil nitrate N concentrations were elevated with compost 'B' and 'C', especially with the addition of 220 lb N/acre. In subsequent years, fall soil nitrate N concentrations increased with compost in combination with N fertilizer.