A modified centrifugation technique for obtaining soil solutions was developed and compared to immiscible displacement technique using different immiscible liquids. Coefficients of variation and standard deviations for ionic composition of soil solutions obtained by the modified centrifugation method were consistently lower than those of immiscible liquids. Differences in the estimated concentrations and activities for Ca, Mg, K, and Al among the methods employed to obtain soil solutions were noticed. The largest disagreement between activity values occurred for Al species. Such discrepancies necessitate the use of the modified centrifugation technique to obtain soil solution especially when Al determination and speciation are critical. The modified centrifugation technique offers a reliable, rapid, contamination‐free, and inexpensive method for obtaining soil solution for chemical characterization. Practical aspects of the technique (relative centrifugal force, centrifugation time, and filtering materials) are discussed.

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Fluidized bed combustion, a desulfurization process for coal‐fired power plants, produces a waste that contains large amounts of calcium oxide and calcium sulfate. Since approximately 200 kg of fluidized bed combustion waste (FBCW) is generated per metric ton of coal burned, it represents a significant potential source of lime that must be evaluated before it can be properly utilized. In this study, FBCW was compared with calcium hydroxide as a lime source in a greenhouse study with red clover, tall fescue, oat, and buckwheat. The FBCW and calcium hydroxide were applied at rates calculated to adjust the pH of Westmoreland silt loam (Ultic Hapludalf, mixed, mesic) to 5.0, 5.5, 6.0, and 6.5. Though the loading rates from FBCW were higher than those from calcium hydroxide, FBCW treatments increased Ca levels more than did calcium hydroxide only in red clover. Only dry matter yields of buckwheat were higher for FBCW than for calcium hydroxide applications. All species showed higher FBCW‐induced Mg and S increases than hydrated lime. In spite of the Zn loading, Zn levels in herbage decreased as the pH levels increased as a result of FBCW application. Soil pH increases in FBCW and Calcium hydroxide treatments were comparable when the materials were applied in equivalent amounts. It was concluded that FBCW may be valuable as a lime, Mg, or S source when the effects of heavy metals in the material are evaluated.

Six legume species and several varieties within the species were grown in a greenhouse pot experiment using the Bt horizon of a Lily (Typic Hapludult) soil. Lime treatments were 0 and 2.2 g Ca(OH) 2 /kg soil. Liming increased the soil pH from 4.6 to 6.2. The species and varieties responded differentially to lime. Both shoot and root growth of legumes showed a significant species and lime interaction effect. Based on tolerance index groups for shoot growth, alfalfa varieties were classified as very sensitive, red clovers and white clovers as sensitive and Essex soybean and Carroll birdsfoot trefoil as tolerant to the acid soil. The remaining legumes were grouped as moderately tolerant to the acid soil. Liming increased shoot concentrations of Ca in all the legumes and reduced concentration of Mg, K, and Zn. Species and varieties within species differed significantly in concentrations of all mineral elements studied except Mg. Further significant differences in elemental composition were observed due to both lime and lime species interactions. In the 1079