An evaluation of the productivity of some important soil types in the Central Basin of Tennessee

The purpose of this study was to develop reliable crop-yield indexes for some of the major soil types that occur in the Central Basin of Tennessee. The yield indexes developed are based on data from plot tests in which the soil types and the management levels have been defined. Many of the tests have been conducted over a considerable number of years during which a range in climatic conditions has been experienced. Thus the crop-yield indexes reported in this study should represent the average crop yields that may be expected from the use of specified soil management practices on the given soil types. Such information should provide a basis for comparing the crop producing abilities of the different soils under different levels of management and for predicting the yields on similar soils with a like combination of properties that affect crop growth.

The comparison of different soils as to their productivity has often been based on personal estimates of the average annual yield of a crop, on interviews with farmers, or on extensive studies of farm records. Frequently, differences in the productive capacity of various types of soils have been expressed simply by such terms as "supermarginal'' and “submarginal". There is a need for a more objective means of evaluating the relative productivity of soils for different crops, such as by accurate yield data on representative soil types collected over a period of years. The resultant yield indexes should prove an important aid in land use decisions during development of farm management plans, and a helpful measure of the crop production efficiency of individual farmers.