A lime requirement test for maritime Canada, and response time and effect of liming source on soil ph

Abstract

Abstract An experiment was conducted to determine which of the two lime requirement tests (LRT) used in Maritime Canada (Adams‐Evans, SMP) are most appropriate, and to evaluate the effect of two sources of limestone (calcitic and dolomitic) on soil pH during a four month incubation period. Four soils, varying in texture from loamy sand to silty loam, and three rates of each lime were used in the study. The LRT showed that for three of the four soils, the two tests recommended similar amounts of lime; the middle rate of lime was the amount suggested by the LRT. Based on the final month analysis, it was noted that both the Adams‐Evans and SMP methods over‐estimated the lime requirement; consequently, the Mehlich buffer was tried on the four soils and compared to the other methods. The result showed that the soil pH stabilized after about two months of incubation. There was a very different pH response to the two lime sources, calcitic lime increased soil pH about 0.5 units above that for dolomitic lime; however, the difference was somewhat soil and rate‐dependent Lastly, the data indicated that the recommended rate of dolomitic lime suggested by the Mehlich LRT was the most appropriate.