Wednesday, November 7, 2007
296-25

Soil pH and Available Nutrient Changes Two Years after Application of Liming Materials in Mississippi.

William Evans, Mississippi State University, 322 Hunters Ridge Dr., Clinton, MS 39056-9661 and Larry Oldham, 117 Dorman Hall, Mississippi State University, Mississippi State University, Mail Stop 9555, Mississippi State, MS 39762.

Locally available liming materials were applied to replicated plots in Mississippi. Materials included dolomitic and pelleted limes, bagged and bulk limes, and slags being marketed for soil pH management. Treated plots received a surface application of 4.5 Mg ha-1 of their assigned material in April 2005. The material was then tilled into the surface 15 cm on the day of application. Plots were sampled at 0, 30, 60, and 90 days after treatment (DAT), then approximately every 90 days through summer, 2007. Pre-application soil pH ranged from 6.4 to 6.6 among the four replicates.  Soil pH remained significantly elevated in each treatment 24 months after application (MAA), ranging from 6.8 to 7.5 (untreated pH = 6.4 at 24 MAA).   Differences in soil test Ca and Mg levels were also present.  Neither liming nor lime source significantly altered soil test S, Zn, Na, or soil organic matter levels.  Soil pH changes in response to treatment have differed indicating significant differences in the influence of the materials on soil pH under the Crystal Springs conditions to date.  The study will follow soil pH in the plots for one more year or until there is significant decrease in pH down to or near the initial pH levels.