There is growing evidence about the significance of organic carbon in the nutrition of non-leguminuous crops (See Anoop Kumar Srivastava's contribution recently and his references). As a result, it seems logical that crops grown in soils with higher organic carbon will have access to more N directly and indirectly by mineralization- better than those with low soil organic C. if this is the case, should it not be wise to adjust the "blanket" N fertilizer rate recommended by soil testing labs particularly for those crops that prefers organic sources of N?