Northern Research and Demonstration Farm
It is common to see large-scale, egg-laying units in many parts of Iowa. Although most plants ship the eggs intact,some facilities have begun to ship liquid eggs. The eggshells, at locations that ship liquid eggs, are ground, stockpiled, and applied to farm fields. Farmers want to know if the eggshells have value as a lime source, and if so, at what application rate. This experiment evaluated the usefulness of ground eggshells as a lime source. The study compared soil pH change and crop yield attained at multiple ECCE rates for traditional agricultural lime and ground eggshells.
Iowa State University
Holmes, John D. and Rueber, David, "Use of Ground Eggshells as a Lime Source" (2007). Iowa State Research Farm Progress Reports. 933.