Search this site:

Southern Native Plant Communities in Historical Times

Information about the historical native plant communities of the region can be difficult to interpret. Since the modern concept of a plant community did not evolve until the late 19^th and early 20^th centuries, earlier writers seldom included the kind of information we would like to have for this Assessment. Also, most common paleobotany methods have limited value in the study of historical vegetation, because they have poor resolving capabilities over the relatively short period of the last 500 years. These difficulties aside, there is currently a great deal of interest in the nature of native plant communities at the time of European settlement, largely motivated by the current trend toward restoring such plant communities in the South.

Although Europeans began to explore and settle the Southeast by the mid- and late 16^th century, their impact on the native plant communities of the region was limited largely to Coastal Plain, savanna, and bottomland forests. For the most part, the earliest settlements were established in coastal areas and on broad river terraces accessible by boat and barge. Even the rare interior settlements, such as the Arkansas Post established in 1686, were built along major rivers to avail themselves of local patterns of commerce. These areas were often cleared to make way for agriculture. Some of the clearings were made for subsistence farming, but the largest were made for commercial farming and livestock production. The quantity of timber taken during this time was limited both by technology and local demand. Consequently, large areas of upland forest in the South went essentially untouched until the 19^th century.

The exploitation of natural resources, such as timber and forage, increased as population increased and as an industrial base was built in North America. Improved agricultural efficiency, a growing population, and better access to European markets by the end of the 18^th century provided both the motivation and the capital necessary to expand the conversion of native vegetation to agriculture (Carrier 1923). People began to move westward into the interior of the region and began to clear increasingly large tracts of land. In this era of increased trade, additional exotic species were introduced to the South, and exotic plants that had become well established moved with the expanding population.

Although the Native American population had declined significantly, these people were sufficiently common in the early 18^th century to exert a continued impact on wide areas of the southern landscape through their agriculture and, more importantly, their use of fire as a means of manipulating vegetation. The aboriginal practice of burning the forests was adopted by European settlers soon after permanent settlements were established.

Like the Indians, the European settlers of the interior South tended to choose specific areas in which to build homes and farms. Relatively flat topography, access to water and timber, and proximity to trade routes via waterways or overland were important criteria for settlement sites. Such places are most typically found either along the terraces of large river systems or on the Coastal Plain. Consequently, riverine forest communities and longleaf pine communities were the first natural vegetation types in the interior South to be impacted by the expansion of European settlement. However, these native plant communities had long been inhabited by aboriginal people. In some cases, the Europeans removed the Indians by force so that they could occupy their land. Europeans selected and exploited other areas on the basis of their strategic value for military outposts or their proximity to mineral resources. These areas were less common but usually had equally significant impacts on the local vegetation.

Until the 20^th century, the economy of the South was based largely on agriculture. Technology changed the kinds of crops grown, especially for the export market. From the late 18^th century until the early 20^th century, resin extraction from pines, especially longleaf pine, for use by American and European navies shaped the management of longleaf pine forests in the Coastal Plains. The naval stores industry, based on the processed and unprocessed resin, or tar, used to seal the hulls of ships and many other things, began to decline with the development of metal hull ships at the end of the 19^th century. Large farms became common in the region by the early 19^th century, due in great part to technological improvements like the invention of the cotton gin in 1793. Until the beginning of the 19^th century, tobacco accounted for the majority of southern exports; thereafter and well into the 20^th century, mechanized cotton production dominated the South. Large tracts of agricultural land were created out of the native plant communities of the Coastal Plain where cultivation was relatively easy. This form of land use also greatly affected longleaf pine communities, as well as a wide range of hardwood communities that existed on river terraces.

Increases in farm size had the effect of concentrating economic power in the hands of relatively few established families and companies. There was little incentive for these families to develop new centers of agriculture or diversify the crops being grown. The majority of new settlements in the interior South were based either on a subsistence economy or service to relatively small areas. Certain areas were completely converted to agriculture, with permanent and deleterious implications for the native plant communities. In areas dominated by subsistence farming, less obvious impacts to the native plant communities occurred, such as the disruption of population processes caused by fragmentation, the introduction of exotic species, impacts on rare communities such as mountain bogs and glades, and widespread alterations in forest community structure related to timber harvesting and fuel-wood gathering.

There was considerable curiosity in 17^th and 18^th century Europe about North American ornamental and medicinal plants. In fact, most of the “botanists” of this time were collectors for wealthy Europeans. These botanists, however, usually did not catalog the natural resources of the region. It was left to the early 18^th century botanists from the Northeast to first explore and describe the vegetation of the Southeast. Most notable among these early explorers were John (1699–1777) and William Bartram (1739–1823).

The Bartrams made several journeys of botanical exploration and collection and published accounts of the natural history of the areas that they visited. William Bartram’s “Travels through North and South Carolina, Georgia, East and West Florida . . .” became an international bestseller shortly after being published in 1791. This success was no doubt due in part to John Bartram’s reputation and to his and William’s extensive correspondence with European botanists. William Bartram states that the purpose of his trip through the South was the “discovery of rare and useful products of nature, chiefly in the vegetable kingdom,” and to “obtain specimens and seeds of some curious trees and shrubs (which were the principal objects of this excursion).”

Although “Travels through North and South Carolina, Georgia, East and West Florida . . .” is full of details of soil conditions in various places, lists of species encountered, and in some cases detailed descriptions of particular species, Bartram did not generally offer useful accounts of the native plant communities. He did record the occurrence of many of the broad community types we are familiar with, including forests, savannas, glades, and swamps, described in such terms as “…expansive green meadows or savannas, in which are to be seen glittering ponds of water, surrounded at a great distance, by high open pine forests and hommocks, and islets of oaks and bays projecting into the savannas . . . .”

He also noted large areas of clearcut longleaf pine (Bartram 1791, p. 312) and “expansive ancient Indian fields” (Bartram 1791, p. 458). Bartram was particularly interested in the agricultural potential of the South, noting not only the areas used by the aboriginals for cropping (e.g., Bartram 1791, p. 511), but also areas that would be suitable for the cultivation of European crops as diverse as olives and oranges (Bartram 1791, p. 337). He also documents the early trade in useful native plants such as ginseng (Bartram 1791, p. 327) and rosinweed (Silphium) (Bartram 1791, p. 398). Bartram also offers accounts of introduced species such as barnyard grass (Echinochloa) (Bartram 1791, p. 430) as well as a description of Franklin tree (Franklinia altamaha) (Bartram 1791, p. 467), a species that is now extinct in the wild. Perhaps most remarkable about the landscapes described by Bartram is that many of these places remained unchanged until the late 19^th century.

Thomas Nuttall, traveling in the Arkansas Territory around 1819 (Nuttall 1821), also described what he saw in general terms: thickets of dwarf oaks, hills of pine and oak, and scattered areas of prairie. He too noted the effect of the human hand on the landscape, mentioning annual fires set by the white settlers and extensive areas of cutover pine. Nuttall cataloged many nonwoody plants as well. As was customary at the time, he did not elaborate about the specific conditions in which these plants were growing, but simply stated this or that species was growing under oaks, along streams, or high upon a hill.

Bartram and Nuttall are the most important of the early botanical explorers of the South, but their work is of limited value in determining the nature of native plant communities in existence at the time. Their approach reflected the contemporary philosophy of natural history and botany. At the beginning of the 19^th century, ecology was not yet a word, much less a science. Linneaus had developed his natural classification system only a half century earlier; there was not yet a concept of natural selection or evolution, and it was a time of global exploration and discovery. All of the major seafaring European nations were establishing colonies around the World. The purpose of this exploration was the acquisition of power and wealth, and because many plants were the source of great wealth, botanists were needed to travel to “unexplored” parts of the World to catalog the plant life. At the time, this was called phytogeography, a term that describes the endeavor well enough. The primary concern of phytogeographers was to identify the location and distribution of plant species. While phytogeography was a necessary step in the development of plant ecology, at the beginning of the 19^th century little effort was expended on describing the interrelations among the species that were being so faithfully cataloged.

After Bartram and Nuttall, a procession of botanists and naturalists, often physicians with an interest in botany, collected plants in the areas around their homes. For the most part, these collectors did not directly contribute to the understanding of the distribution of native plant communities. However, their work would become important later, in the late 19^th and early 20^th centuries, as regional floras for the South were developed.

In 1835, the first railroad system in the South began operating in North Carolina, in the heart of the longleaf pine forests of the Coastal Plain (Croker 1987). The industrial revolution had brought to the South the means by which its abundant forest resources could be transported great distances and still turn a tidy profit. The longleaf pine forests of the Coastal Plains were not only a source of high-quality timber for a growing population, but also the Nation’s most important source of naval stores. The naval stores industry began in North Carolina and spread throughout the Coastal Plains with the railroad (Croker 1987). By 1854, the railways had reached the Mississippi River.

In the mid-19^th century, clearcutting was the primary logging method employed. Modern forestry, as practiced in Europe at the time, would not become commonplace in North America until the early 20^th century. In the first half of the 19^th century, extensive areas of forest were leveled to create pastureland. In many places the native forest has never recovered. Forested areas surrounding major river ports were extensively cut to fuel steamboats. Vast acreages of wetlands and river terraces were drained or plowed by the mid-19^th century, causing significant losses to local biodiversity in some areas. Strip mining, especially for coal to stoke hungry steamboats and railroad locomotives, became commonplace where deposits were sufficiently shallow to exploit, such as the Upper Cumberland Plateau. Strip mining eliminated forest cover and frequently altered or killed riparian and aquatic plant and animal communities downstream from the spoil piles. Although much of this activity in the region slowed during the 1860s, logging resurged quickly thereafter. By the 1880s, a broad sector of Americans, mostly in the Northeast and West, were becoming concerned about the unbridled exploitation of the Nation’s forest and wetland resources.

The evolution of forest protection laws and the establishment of national forests in the South parallel the development of the modern conservation movement in the United States (Williams 2000). Issues such as farmland erosion, forest clearcutting, and the hyperexploitation of buffalo were on the national conscience. The first use of the word conservation in the context of the protection of natural resources was in 1875, by John Warder, president of the American Forestry Association. The leadership of America’s conservation movement was borne by Gifford Pinchot, John Muir, Charles Sargent, and Theodore Roosevelt.

The Federal Government began setting aside tracts of land as forest reserves when Congress passed the Forest Reserve Act of 1891 (Williams 2000). This legislation allowed the President to “from time to time, set apart and reserve, in any state or territory having public land bearing forests, in any part of the public lands, wholly or in part covered with timber or undergrowth, whether commercially valuable or not, as public reservations …” Federal forest administration was consolidated under the leadership of Gifford Pinchot in 1905 with the establishment of the U.S. Department of Agriculture’s Forest Service (Williams 2000). The first national forest established in the South was the Arkansas National Forest (1907). Two national forests in Florida were added to the growing system in 1908 (Ocala and Choctawhatchee). Most of the national forests throughout the South are a result of the Weeks Act of 1911. This act broadened the mandate of the Forest Service and provided for the purchase of land, largely for watershed protection. From the time of their establishment until the beginning of the Second World War, the national forests of the South served primarily as conservation areas (Williams 2000). National forest lands have since been critical refuges of functional native plant communities in the South.

At the turn of the 20^th century, the logging industry in the South was producing lumber at its historical peak. So much forest land had been logged out that timber companies were finding it difficult to access merchantable trees and were beginning to close mills and move to the newly opened virgin timberlands of the Northwest. Although the First World War caused a short-lived resurgence in the demand for timber and naval stores, the conversion of the shipbuilding industry to steel by 1920 caused demand for southern timber and naval stores to fall drastically. By 1930 the majority of the Coastal Plains longleaf pine communities had been essentially cut over (Croker 1987), as had the interior shortleaf pines (P. echinatus). Upland hardwood forests fared somewhat better, at least in some places.

After 300 years of land conversion and alien plant introduction, it is no surprise that in the early part of the 20^th century exotic plant species were common throughout the region. Some had been planted purposefully as ornamentals, as forage for livestock, or increasingly as erosion control agents by State and Federal agencies. Others were simply accidental tourists that made their way across the region without the direct assistance of people, in stocks of hay or the coats of domestic animals. Palmer (1926) notes an abundance of “introduced species [and] adventive woody species” in the vicinity of Hot Springs, AR. He specifically noted Japanese honeysuckle (Lonicera japonica), Princess tree (Paulownia tomentosa), and many other introduced species.

Vascular plants were not the only exotic species introduced to the United States during historical times. Among the most destructive exotics were fungal pathogens of trees. Chestnut blight (Cryphonectria parasitica) was introduced into this country in New York in 1904. It spread rapidly and was actively killing trees in the Southern Appalachians by the 1920s. By the early 1950s, American chestnut (Castanea dentata) was ecologically extinct throughout its range in Eastern America. This species once was a dominant tree of Appalachian forests. In some areas, one tree in four was a chestnut. Although loss of the chestnut was significant in terms of change in forest composition, there is some disagreement about the ecological impact of chestnut blight. Only one species extinction is suspected to have resulted from the blight (American chestnut moth, Ectodemia castaneae); and the greatest impacts to native plant communities seem to have been a change in tree density (a temporary result of canopy gaps created by the death of chestnuts) and a realignment of dominant overstory tree species resulting from competition (Stein and others 2000, Woods and Shanks 1959). Different trees have replaced the chestnut as the dominant canopy species in different portions of the chestnut’s former range.

Dutch elm disease (Ophiostoma ulmi and O. nova-ulmi) entered the United States in 1930 in logs imported from Europe. There is differential susceptibility among Ulmus species, but the American elm, a common street and landscaping tree, has been the hardest hit. By the late 1970s Dutch elm disease was known to have impacted elm trees throughout the country (Schlarbaum 1997).

Butternut canker (Sirococcus calvigigenti-juglanacearum), which impacts Juglans cineria, was first observed in the United States in 1967, but it is believed to have been infecting trees for many years by that time. By 1995, the USDA Forest Service estimated that over three-quarters of all butternut trees had perished from the disease (Schlarbaum 1997).

There have been many other exotic disease-causing fungi and insects that have had significant impacts on the native plant communities of the South. Examples include white pine blister rust (Cronartium ribicola), the gypsy moth (Lymantria dispar), and the balsam wooly adelgid (Adelges piceae). Many introduced disease organisms are still impacting our native plant communities, and it is likely that new pests will be periodically introduced to our region. No one can tell what damage they might bring in the future. For a more thorough discussion of the impact of exotic diseases of forest trees, see chapter 17 of this report.

The study of the flora of the South was in some respects dependent on the publication of local and regional floras. Improvements in the knowledge of the botany of the region required these tools. Several local floras had been published for portions of the South, including Walter’s Flora Caroliniana (1788), Mohr’s Flora of Alabama (1901), and Gattinger’s Flora of Tennessee (1901). The first comprehensive flora of the Southeast was published in 1860 by Chapman. It was an important though incomplete work. Unfortunately, it seemed to stifle further serious assessments of the local flora of the region until the early 20^th century. It was not until 1903, with the publication of Small’s Manual of the Southern Flora, that the region had a comprehensive, systematic flora. Revised in 1933, Small’s Manual is a monumental work of 1,500 pages and was the standard of southern botany floras for over 50 years (Reveal and Pringle 1993). The last 20 years have seen the development of several important new floras [e.g., Smith (1994) and Wunderlin and Hansen (2000)].

The lack of specific information about native plant communities in the South from settlement times to the end of the 19^th century is the product of two conspiring circumstances. First and foremost, the Southeast has been continuously occupied for longer than any other region of the United States: by the early 19^th century when the Nation became interested in its natural resources, the focus was on the wild and unknown West rather than the familiar South.

Secondly, the development of plant ecology as a modern science took place largely in Europe beginning in the early and mid-19^th century. There and then the concepts of succession and plant associations were first developed into forms recognizable today. However, at the time, the study of plant ecology was a subdiscipline of plant geography. Plant geography, the description of the distribution of plants, was the primary concern of European academics, capitalists, and naturalists. In the 19^th century, naturalists from many nations were traveling around North America cataloging plants. The pinnacle of plant geography studies was reached in the early 20^th century and coincided with the rise of the modern study of plant ecology. The earliest focus of the fledgling field of ecology was the study of plant community succession. That research was done in the midwestern plains and eastern forests.

Henry Cowles first described the dynamic (changing) nature of vegetation. Prior to Cowles, plant geographers were content to map the current condition and extent of vegetation. Many of Cowles’ students went on to make important contributions to the study of succession throughout North America. E. Lucy Braun became renowned for her descriptions of virgin forests in the Eastern States, especially the Appalachian Mountains. Her work is still read and used as a reference.

Fredrick Clements was arguably the first community ecologist in America. Working largely with prairie and old-field communities in the Midwest, Clements described much of the vegetation of North America, named many plant associations, and identified successional stages for his named communities. He described the plant community as a form of superorganism to indicate his perception of the interdependence of all of the parts of a community, and he described succession as the development or life cycle of the organism.

Clements’ notion of the superorganism was not universally accepted. In 1926, Henry Gleason, who conducted his research in forested communities similar to those common throughout the South, wrote an influential paper that criticized Clements’ views and posited that the nature of plant associations is determined by the individualistic behavior of plant species. Gleason’s individualistic notion of plant communities eventually won out over Clements’ idea of the superorganism.

The complexity of southern forest plant communities hampered the development of a comprehensive and consistent community classification system, such as those developed early in the history of land management in the Midwest and West.

Beginning with the study of plant succession in the first quarter of the 20^th century, a practical science of plant and community ecology evolved. From this point forward meaningful data became available about the nature of native plant communities. However, because the South had been settled for centuries, by the early 20^th century, vast tracts of native plant communities had been converted, planted, logged over, infested with weeds, or otherwise impacted, so opportunities to study intact native communities were rare.

The Great Depression of the early 1930s was exceptionally difficult for the people of the South, but it did a lot for the native plant communities of the region. The Federal Government purchased land and established many national forests. The Civilian Conservation Corps (CCC), established in 1933 during the Franklin Roosevelt administration, did extensive reforestation in the South. The formal teaching of forest sciences in the United States had finally matured by the 1920s and 1930s so that an abundance of well-trained foresters working for the USDA Forest Service, State forestry agencies, and the CCC itself were available to supervise and direct the work (Williams 2000). The fledgling USDA Forest Service was working to control unauthorized timber cutting on Federal land. Unfortunately, this was also the time in which widespread fire suppression activities began. Although this practice was well intentioned at the time, it eventually led to significant declines in native plant communities throughout most of the Southeast.

The timber industry in the South remained depressed until the outbreak of the Second World War. At about the same time, serious scientific research was started at government and university labs to increase the productivity of forest land. Much of this work focused on the development of “improved” tree selections and cultivation practices. One of the innovations that arose was the growing of pines in plantations.

Plantation cultivation of pines turned out to be exceptionally productive. Newly developed tree selections thrived in the prepared conditions of the plantation. Large tracts of cutover land, especially in the Coastal Plain and Piedmont, would eventually be converted to pine plantations. This method focused timber production on developed sites. Although those sites were forever altered, this intensive form of silviculture saved many acres of native forest from more traditional timber harvesting.

The next large threat to native plant communities in the South came from another, unlikely advancement in technology. From the time of settlement the South was largely rural, agrarian, and sparsely populated. The widespread availability of air conditioning in the 1950s and 1960s made living and conducting business much easier in the sweltering heat of southern summers. The South, therefore, began to see significant increases in immigration and urbanization. Land was developed, and large tracts were fragmented. These trends led to rapid increases in demand for building materials, electricity, and additional agricultural production.

Improvements in technology and mechanization (especially in agriculture) and decreasing Federal commodity price supports led to significant consolidations in the timber and farm industries. Former farmers migrated to cities in the North and South. In the 1940s, 42 percent of the population in the South lived on farms. By the 1950s, only 15 percent of southerners lived on farms. The majority of the population of the region became isolated from the landscape, forever changing the way southerners viewed their forests.

After the end of the Second World War, pine forests in the South, including those on State and Federal land, were predominantly managed for timber production. The birth of the modern conservation movement in the 1960s came, in part, as a reaction to concerns about public land management priorities and the lax enforcement of environmental laws.