Fig. 2. Nitrogen uptake by wheat (aboveground organs) with time in the first, second, and third years of fertilized (solid lines and filled symbols) and control (dashed lines and empty symbols) plants and application of sewage sludge compost (SSC, solid lines and filled symbols) and cattle manure compost (CMC, dashed lines and empty symbols) at three rates (3, 6, and 12 kg m^–2 yr^–1). Each point represents the mean of four replicates (10–20 plants per replicate) and the bars represent the SE.