It is often said that “you are never too old to learn” but a quick look into the history of ag technology reveals the limited tools and information available for learning a few short years ago. Some of the earlier work in soil testing began in 1945-1950 and commercial fertilizers were not readily available until the 1960’s. Producers of this era had limited learning resources available as the university extension programs were in their infancy and they had to rely on experience, personal observation and interaction with their peers to make management decisions.
Early gypsum mining operations began in the late 1800’s and it was observed that the grass and plants near the mine entrance were green and lush compared to areas away from the mine and it was likely due to the application of sulfur as the miners tracked dust from the mine and walked across the grass areas. This prompted some of the first experimentation of applications of gypsum to crop land. Sulfur deficiency was likely not well understood at the time but through the knowledge gained from direct observation they were able to improve crop production.
The concept of pH was developed in 1909 by a Danish scientist named Sorensen and the first electronic method of measuring pH was invented in 1934 by Arnold Beckman at California Institute of Technology working with a small start-up company called Sunkist. They were looking for quick and easy method of testing the acidity of lemons.
My grandfather completed the 8th grade in 1927 as this was the highest educational opportunity available to him and he began farming in northeast Missouri at that time. The only available fertilizer material was manure and he was beginning to experiment with lime applications approximately 25 years after Sorensen first described the concept of pH. I remember him describing his lime recommendations based on his personal observations in this manner, “When the soil will not produce good sweet clover, add 2 tons of lime.”
He grew hay crops of sweet clover and lespedeza as he observed it was well adapted to the low fertility soil conditions at the time. From a University of Missouri Extension publication, “Sweet clover has an extreme range of adaptation. About the only consistent requirement is one of high pH. Sweet clover needs a high pH, 6.0 or higher, for proper nodulation to occur, and it has a higher calcium requirement as well. Sweet clover is able to obtain phosphorus from relatively unavailable soil phosphates and will grow on soils where alfalfa, red clover or ladino will fail. Except for its high lime requirements, it is similar to lespedeza, which tolerates very low fertility conditions.” It appears his personal observations led him to a very suitable cropping choice.
The fertilizer supply chain developed and improved through the 70’s and 80’s and the first yield monitor came on the scene in 1992. Grid soil sampling and intensive management practices and management options continue to improve every season but it is important to stay grounded in the basics. Keep learning and continue to hone your skills of personal observation.
Written by Stan Miles, ALGL Agronomist