Dominance of Soybean Cropping in the Lower Mississippi River Valley

DOMINANCE OF SOYBEAN CROPPING IN THE LOWER MISSISSIPPI RIVER VALLEY L. Arnold Siniard" The Lower Mississippi River Valley as an agricultural subregion is the leading producer of soybeans in the United States South. Moreover, the intensity of soybean culture is higher than in any other United States agricultural region or subregion. Earlier studies by Prunty, by Munn, and by Siniard, (1) have discussed the rapid growth in acreage devoted to soybeans and the parallel decline in acreage planted to other crops, especially corn and cotton. Since data from the 1969 agricultural census have become available, it is now possible to show the parallel between changes in harvested cropland acreage and changes in soybean acreage. That a parallel exists is apparent from an inspection of the raw data. This paper shows where and why these changes have occurred and gives further evidence of changes in the relative importance of the traditional crops of cotton and corn, and in certain areas, rice and sugar cane in terms of land use. The primary areal focus is the Lower Mississippi River Alluvial Valley, henceforth referred to as the Alluvial Valley to avoid monotonous repetition. It extends from the vicinity of Cape Girardeau, Missouri, to the Gulf of Mexico. Thornbury called it the Mississippi Alluvial Plain which he divided into the Alluvial Valley and the Deltaic Plain. (2) As an agricultural region it includes not only the area which, were it not for man-made levees, would be flooded by the highest water levels of the major stream, but also the lower valleys of tributary streams and low terrace lands, or "cones," of alluvial origin within the major valley. (3) The major tributary streams include the Red, Ouachita, Arkansas, White, and Yazoo Rivers. Major identifiable basins within the region include the St. Francis, Yazoo, Tensas, and Atchafalaya Basins (Figure 1). (4) In order to show contrasts with adjacent areas, included in the study region are the entire states of Arkansas, Louisiana, Mississippi, the parts of Tennessee and Kentucky lying west of the Tennessee River, and a small portion of southeastern Missouri. Those counties having more than one half of their area within the Alluvial Valley are called alluvial counties; the remainder are referred to as upland counties. CHANGES IN AMOUNT OF HARVESTED CROPLAND. Acreage of harvested cropland in the study area reached a peak during the 1930's, then declined during the next two decades. (5) The decline can be ex- •Mr. Siniard is instructor of geography at Memphis State University. This paper was accepted for publication in June 1974. 18Southeastern Geographer LOWER MISSISSIPPI RIVER ALLUVIAL VALLEY SOURCES: U.S. GEOLOGICAL SURVEY, GEOLOGIC MtP OF THE UNITED STtTFS. I960 NEVIN M. FENNEMAN, PHYSIOGRAPHY OF THE EASTFRN UNITFn STATES (NEW YORK, 193$, P. 91 Figure 1 Vol. XV, No. 1 19 plained partly by acreage restrictions on cotton and rice imposed by the federal government under the Agricultural Adjustment Acts. When the government reduced allowable planted acreage, farmers reacted by increasing their fertilizer applications and by using their most productive soils. The less-than-desired drop in production led government officials to lower allotments still further. Another factor in the decrease in harvested cropland was the replacement of animal draft power by inanimate power which reduced the local demand for corn for horse and mule feed. Although cattle raising increased in response to greater demand for feeder cattle in the North Central States, these cattle generally were not raised on grain but on hay and pasture. These changing conditions led to the removal of a large quantity of farmland from cropping. Much upland, eroded and depleted from row cropping, was converted into pastureland. Some was held out of production temporarily under government sponsored soil conservation programs , some was planted to pine, some was abandoned, (6) and a relatively small amount was taken for urban uses. The early peak in acreage reported by the Census Bureau had been reached in 1929 in Louisiana and the western portion of Tennessee, and in 1939 in Arkansas, Mississippi , and western Kentucky. The southeastern Missouri counties, mainly within the Alluvial Valley, had a steadv increase from early settlement up to 1969. The low point in harvested cropland was reached generally in...