Date of Award
Master of Science
M.E. Springer, Curtis Lard
Sound adjustments in farming require accurate predictions of costs and returns for different crops and their most profitable allocations in a cropping system for various soil, climatic and management conditions. It is imperative that one should know the relationship between crops and soils to make these adjustments. For profitable crop production, both physical and chemical characteristics of the soil must be taken into consideration. Physical properties such as texture, structure, drainage, presence of pans, depth and available moisture supplying capacity greatly influence the suitability of a crop to a particular soil and the most profitable allocation of a crop in a cropping system.
After the physical aspects of soil-crop suitability have been considered, the fertility status of the soil should be taken into consideration. By combining physical relationships regarding crop suitability to soils with available fertility level, better estimates of crop yields can be established. A knowledge of the available soil fertility level may also provide a logical means for determining the effect of available fertility level of soils on the most profitable crop allocation.
The University of Tennessee in cooperation with the Tennessee Valley Authority and the Soil Conservation Service initiated a study in 1964 to determine the effects of soil suitability, available fertility level and farm size on the estimated returns and most profitable allocation of crops among soils of the Sequatchie Valley. The purposes of this study were:
1. To aggregate the soil mapping units in the Sequatchie Valley into groups that would have similar yield potential and give similar response to fertilization and other management inputs.
2. To determine the level of phosphorus, potassium and pH of the soils of the Sequatchie Valley.
3. To estimate costs and returns from selected crops as affected by soil management group, soil fertility level and farm size.
4. To determine the optimum allocation of crops among the various soil groups at different fertility levels and farm sizes using net return to land, labor and management as the sole criterion for allocation.
5. To determine the allocation of selected crops among the various soil management groups using net return at different fertility levels and farm sizes but restricting the allocation by using certain soil loss tolerance values.
Homesley, William Larry, "Effects of agronomic and management factors on estimated returns from selected crops in Sequatchie Valley. " Master's Thesis, University of Tennessee, 1966.