The Role Of Phosphorus In Agricultural Development In Kentucky: A Story Of The Haves And The Have-Nots
John Ragland1, Dennis B. Egli1, Katsutoshi Mizuta2, Stephen Greb3, and Jeffrey E. Levy4
LEXINGTON, KENTUCKY
Early agricultural development in Kentucky was a matter of the Haves and the Have-Nots. Farmers in the central Bluegrass region (the Haves) produced bumper crops that formed the basis for a thriving, wealthy, prosperous society. Most of the rest of Kentucky was characterized by low-yield subsistence farming (the Have-Nots).
A member of Daniel Boone’s party wrote in his travel journal after reaching central Kentucky in March of 1775 - “So rich a soil we had never seen before; covered with clover in full bloom, the woods abounding with wild game – turkeys so numerous that it might be said they appeared as one flock, universally scattered in the woods. It appeared that nature, in the profusion of her bounty, had spread a feast for all that lives, both for the animals and rational world” (Clark, 1977).
Soil fertility research in the central Kentucky area, conducted by George Roberts (the UK Agronomy Department’s first head) and co-workers in the early 1900’s (Roberts and Ewan, 1920; Roberts and Kinney, 1932), identified the basis for the ‘feast’ by demonstrating that corn yield did not respond to any fertilizer and lime treatments. The native fertility was enough to produce maximum yields (55 to 60 Bu/Acre). These yields were nearly twice that in Kentucky counties outside the central Bluegrass (Fig. 1). The ‘feast’ had its origin in the high levels of phosphorus in the soils in the central Bluegrass.
These soils developed from parent material, the Lexington Limestone, which had an unusually high phosphorus content. Natural phosphatic minerals in the limestone weathered into the high phosphorus soils of Central Kentucky. Originally, the soils were so high in phosphorus that rock phosphate was mined in Woodford County near Wallace Station from 1905 to 1937.
A series of long-term soil fertility plots, funded by a special appropriation from the Kentucky General Assembly in 1926, were established to determine why yields were so low in counties outside of the Bluegrass region. Applying either superphosphate or finely ground rock phosphate doubled corn yields from 25 to 50 bushels per acre (Karraker and Miller, 1958). Corn yields in most of Kentucky outside the Bluegrass were limited by phosphorus.
The Tennessee Valley Authority (TVA) was established by the Federal Government in 1931 to cope with the chronic flooding of the Tennessee River and to generate hydroelectric power to help develop the distressed economies of the thirteen valley states. A strong emphasis on fertilizer development and manufacturing was included in TVA’s mandate. These efforts lead to production and distribution of large amounts of phosphorus fertilizers. President Franklin D. Roosevelt’s New Deal program made these fertilizers available to farmers at little or no cost through the USDA’s Agricultural Stabilization and Conservation Service (ASCS). The widespread use of phosphate fertilizers increased corn yields in the counties outside the Bluegrass until they were essentially equal to those in the central Bluegrass (Fig. 1).
It may be surprising to many of us, especially if we are not soil scientists, that the characteristics of the soil could play such an important role in the development of a region. The high phosphorus soils in the central Bluegrass gave it an early advantage. The rest of the state didn’t catch up until technology made large amounts of phosphorus fertilizers available. The availability of super phosphate worked a miracle and turned the Have-Nots into Haves. As Franklin D. Roosevelt so aptly put it in 1938 “we observe a world of great opportunities disguised as insoluble problems” (Franklin Delano Roosevelt. U.S. President,1933-1945).
Adapted from John Ragland. Dennis B. Egli, Katsutosi Mizuta, Steven Greb and Jeffery E. Levy. 2025. The Role of Phosphorus in the Agricultural Development in Kentucky: A Story of the Haves and the Have-Nots. Kentucky Ag. Experiment Station, University of Kentucky (In Press).
References
Clark, T.D. 1977. Agrarian Kentucky. University Press of Kentucky, Lexington, Kentucky.
Karraker, P.E., and H.F. Miller. 1958. A Summary of Kentucky Soil Fertility Experiments. Bulletin 663. Ky Ag. Expt. Station, Univ. of Ky, Lexington, Ky.
Roberts, G. and A.E. Ewan. 1920. Report on Soil Experiment Fields; Maintenance of Fertility. Bulletin 228. Ky Ag. Expt. Station, Univ. of Ky. Lexington, KY.
Roberts, G. and E.J. Kinney. 1932. Soils and Fertilizer Experiments, Experiment Station Farm. Bulletin 331. Ky Ag. Expt. Station, Univ. of Ky, Lexington, Ky. ∆
John Ragland1, Dennis B. Egli1, Katsutoshi Mizuta2, Stephen Greb3, and Jeffrey E. Levy4
1 Professor Emeritus, Dept. of Plant and Soil Sciences, 2 Assistant Professor, Dept. of Plant and Soil Sciences, 3Kentucky Geological Survey , 4 GIS Program Coordinator, Dept. of Geography: University of Kentucky