This Delta, This Land: An Environmental History of the Yazoo-Mississippi Floodplain

CHAPTER TWO: A True Ecological Complex

The rich deep black alluvial soil which would grow cotton taller than the head of a man on a horse, already one jungle one brake one impassable density of brier and cane and vine interlocking the soar of gum and cypress and hickory and pinoak and ash, printed now by tracks of unalien shapes—bear and deer and panthers and bison and wolves and alligators and the myriad smaller beasts . . . —william faulkner, Big Woods c ha p t e r t wo A True Ecological Complex p ro ba b ly t h e b e s t- k n ow n definition on the geographical extent of the Yazoo-Mississippi Delta has been provided by Delta author David L. Cohn—“[t]he Mississippi Delta begins in the lobby of the Peabody Hotel in Memphis and ends on Catfish Row in Vicksburg.”1 This culturally apt description of the social extremes of a New South plantation empire does not, however, offer enough help in defining the Delta as an ecological complex or as a bioregion; that endeavor calls for classifications provided by the natural sciences. Defining the Delta By the mid-1970s, U.S. public land management agencies had realized how important land classification, on the basis of variations in climate, vegetation, and landform, could be in finding solutions to management 26 A True Ecological Complex 27 problems. The differences were officially recognized in a 1976 map, “Ecoregions of the United States,” which attempted to systematically divide the country into “ecosystem regions.” The map was later supplemented by a book by Robert E. Bailey of the U.S. Forest Service, explaining the principles of the classification system and creating a new taxonomy for American nature. Bailey’s work divided the United States into sixty ecoregions , grouped under four “Domains”—“Polar,” “Humid Temperate,” “Dry,” and “Humid Tropical”—arranged in twelve “Divisions,” thirty “Provinces,” and forty-five “Sections.”2 Section 2312 in this classification, “Southern Floodplain Forest,” is a vast alluvial bed of some twenty-five million acres along the Lower Mississippi from the mouth of the Ohio River to the Gulf of Mexico, ranging from 30 to 40 miles in breadth at its northern end to 150 miles at the river’s mouth in present-day Louisiana. It was created by the meandering Mississippi River and attained its current form during the final cycle of the latest glaciation. Misi Sipi, the “Great River” of the Ojibwa nation, drains the world’s third largest basin. The drainage area of the greater Mississippi covers some 1.2 million square miles, or more than 40 percent of the coterminous United States, from New York to Wyoming. The main channel of the river, from Lake Itasca in northern Minnesota to the Gulf of Mexico, flows southward over a path almost 2,500 miles long. Near its midreach, the Mississippi is joined by its two largest tributaries, the Missouri and the Ohio, and, along its lower reaches, by several other major streams. Below the confluence of the Mississippi and the Ohio, the greatly increased flow results in the formation of the immense stream that supports the vast alluvial plain. In the northern section of the Lower Mississippi Valley, extending from the present-day Cairo, Illinois, to Helena, Arkansas, the river channel is broad and shallow, with numerous islands and sandbars. Below Helena, the channel becomes narrower and deeper and the islands and sandbars less common.3 Among the many floodplains constituting the Lower Mississippi Valley is the Yazoo-Mississippi Delta, which is actually more oval than deltoid in form. The channel of the Mississippi, from Memphis to Vicksburg, forms the western boundary of the Yazoo-Mississippi floodplain. The eastern boundary is defined by a series of bluffs that begin just below Memphis 28 Chapter Two and run south to Greenwood and thence southwesterly along the Yazoo River, which meets the Mississippi just above Vicksburg. The enclosed area is approximately two hundred miles long and seventy miles across at its widest point, encompassing about 4,415,000 acres or some 7,000 square miles of alluvial floodplain from 32.4 to 35.0 degrees north latitude and 90.2 to 91.5 degrees west longitude. The floodplain is relatively flat with a gentle slope to the south, averaging from one-quarter to onehalf foot per mile.4 In addition to the Delta, the 13...