An experiment on a Spodosol (Alfic Haplaquods) was begun for a citrus scion-rootstock trial with three main soil treatments each one hectare in size, namely: shallow tillage (ST), deep tillage to 110 cm by a trenching machine (DT), and similar deep tillage with incorporation of 56 mt/ha of coarse grade dolomitic limestone applied on the surface. Soil samples were taken from narrow profiles of unmixed and those of deep-tilled soil on a DTL area upon opening of tenches for tile-drain installation. Saturated soil extracts were obtained from freshly taken samples and after incubation of subsamples with NH4-N. At depths below 10 cm, shallow lime incorporation resulted in different patterns of NO3distribution, pH, soluble Ca and Mg, and in nitrification efficiency than in corresponding DTL soil. Nitrification resulted in large increases in acidity, amounts of Ca and Mg in solution, and loss of pH-dependent cation exchange. Another set of soil profile samples was taken from the main treatments 2 years after deep tillage. Redistribution of organic matter in Al and Bh horizons in deep tilled profiles was within 25 percent variability of the expected mean values. Increase in P sorption capacity from near nil in A1 and A2 horizons of ST soil to mean values of 0.38 on 0.43 mM/100 g in DT and DTL soil was attributed mainly to Fe and A1 incorporated with the clay from the B21 horizon. Cation exchange capacity was nearly doubled in all depths of DTL soil compared to those in DT soil. About 25 percent of the applied dolomite was unreacted, 40 percent was present as exchangeable Ca and Mg, and 35 percent not accounted for, presumably lost by leaching and outflow in 2 years. Recyling of drainage water by irrigation use is suggested to increase nutrient use efficiency and reduce ground water enrichment.