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The Environmental Origins of Shifting Cultivation: Climate, Soils, and Disease in theNineteenth-Century US SouthAuthor(s): John Majewski and Viken TchakerianReviewed work(s):Source: Agricultural History, Vol. 81, No. 4 (Fall, 2007), pp. 522-549Published by: Agricultural History SocietyStable URL: http://www.jstor.org/stable/20454756 .Accessed: 26/12/2011 15:00
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The Environmental Origins of Shifting Cultivation: Climate, Soils, and Disease in the Nineteenth-Century US South
JOHN MAJEWSKI AND VIKEN TCHAKERIAN
Farmers and planters in the antebellum South held large tracts of unim proved land because they practiced shifting cultivation. Southern cultivators burned tracts of forest growth to quickly release nutrients into the soil. After five or six years, when the soil had been depleted, the old field was aban doned for as long as twenty years. Environmental factors such as poor soils, rugged topography, and livestock diseases accounted for the persistence of this practice, more so than slavery or the availability of western lands. Shifting cultivation slowly declined in the postbellum era, but southern farmers continued to improve a far smaller percentage of their land well into the twentieth century.
IN 1843 JULIAN RUFFIN TOOK CONTROL of Ruthven, a plantation in
Prince George County, Virginia. Hardly representative of the typical planter, Julian-the son of famous agricultural reformer Edmund Ruf
fin-sought to improve and rationalize his plantation operations. His
journal, though, hints at a traditional cultivation regime, one that would
remain an important part of southern agriculture throughout the nine
teenth century. From the start, Ruffin noted that only a small portion of
JOHN MAJEWSKI is an associate professor in the history department at UC-Santa
Barbara. His first book, entitled A House Dividing: Economic Development in Pennsyl vania and Virginia before the Civil War, was published by Cambridge University Press in
2000 and reissued in paper in 2006. He is currently working on a book-length project on
the economic vision of Confederate secessionists. VIKEN TCHAKERIAN taught for many years in the economics department at California State University-Northridge and is
now an independent scholar living in the Seattle area. He has published extensively on the
economic development of the nineteenth-century South.
? the Agricultural History Society, 2007
522
2007 The Environmental Origins of Shifting Cultivation
the farm consisted of improved acreage: "This farm consists of 351 acres ... only about 40 acres are cleared and a great part of this will require
heavy grubbing." For the next six weeks, Ruffin's workforce of six slaves worked hard to clear more land-burning trees and then laboriously removing their stumps and roots-while at the same time plowing fields, building fences, and hauling manure. Ruffin never indicated how much land he and his slaves managed to clear, but given the size of his labor
force it seems doubtful that he made significant inroads into his plan tation's large number of unimproved acres. This reform-minded planter continued to clear land for many years.1
The small percentage of improved land on Ruffin's plantation was typical of the antebellum South. In 1860 southerners cultivated only one out of every three acres of land on their farms, while northerners im
proved more than half of their acreage. Even the recently settled Mid west had a far higher percentage of improved land than Virginia, North Carolina, and other states along the South Atlantic coast. These differ ences resulted from two distinct agricultural regimes. Northern farmers generally practiced what might be called continuous cultivation. Ma nures and rotations kept a high proportion of land in constant use, either for crops or improved pasture, Southerners, on the other hand, practiced a highly commercialized form of shifting cultivation in which a substan tial portion of acreage rested in prolonged fallow. The basic routine of shifting cultivation began with the burning of forest growth to release nutrients into the soil. After five or six years, when the nutrients had been exhausted, the old field was abandoned to weeds, shrubs, and eventually trees. In the meantime, new fields would be burned and cropped. After fifteen to twenty years, the planter returned to the origi nal old field and began the process anew. Originating in the colonial Chesapeake, shifting cultivation remained an important part of southern agriculture for generations.2
Historians and economists have frequently noted the prevalence of shifting cultivation in the South, but there is no consensus as to why it predominated. Slavery, the availability of western land, ingrained cul tural traditions, and environmental constraints have all received blame. Environmental conditions-particularly poor soils, rugged topography, and livestock diseases-strongly correlated with low levels of improved land. While slavery and the availability of cheap western land may have
523
Agricultural History Fall
reinforced shifting cultivation in some areas, the quantitative evidence indicates that such factors played a secondary role. The southern envi ronment bore primary responsibility for the practice's widespread use. Environmental conditions, however, also contributed to southern dis tinctiveness.3
Understanding the environmental origins of shifting cultivation has important consequences for studying the overall development of south ern society. The presence of large tracts of unimproved land reduced
population densities. A dispersed rural population restricted the growth of markets for manufactured goods and urban services while hindering the organization of schools, voluntary societies, and other civic organi zations. In all of these areas, the presence of slavery exacerbated the
impact of shifting cultivation. With both slavery and shifting cultivation constraining social and economic development, it is hardly surprising that the South lagged behind other regions in most measures of long
range economic success. Our strategy was to analyze census data, first collected in 1850, on
improved and unimproved acreage in farms. The census statistics on these kinds of acreage give a rough measure of where shifting cultivation
was used. Counties in which farms and plantations contained high levels
of unimproved land almost certainly practiced some form of shifting
cultivation. We used a multivariate regression analysis of nearly seven
hundred southern counties in 1860 and 1890 to determine how soil types,
topography, urbanization, and railroads influenced southern land-use patterns.
The percentage of improved land on farms serves as our statistical
proxy for measuring the presence of shifting cultivation. The 1860 cen
sus defined improved land as acreage "reclaimed from a state of nature,
and which continues to be reclaimed and used for the purposes of pro
duction," including all land cleared for "grazing, grass, or tillage." In
every census year between 1850 and 1890, the South lagged far behind
the North, with the Cotton South having the lowest percentage of im
proved land (Table 1). In 1850 and 1860 the percentage of improved
land also declined as one moved from east to west. The Midwest, for
example, possessed a lower percentage of improved land than the
Northeast in 1850 and 1860. Yet as areas of the Midwest became more
settled, and farmers had more time to convert forests into farmland, the
524
2007 The Environmental Origins of Shifting Cultivation
Table 1. Percentage of Improved Land in Farms, 1850-1890
States 1850 1860 1870 1880 1890 1900 1910 1920
Northeast 61.6 63.8 65.5 68.2 67.5 59.5 58.1 56.8 Maine 44.8 47.2 50.0 53.2 49.3 37.9 37.5 36.4 New Hampshire 66.4 63.2 64.7 62.0 50.0 29.8 28.6 27.0 Vermont 63.1 66.0 67.9 67.3 60.4 45.0 35.0 39.9 Massachusetts 63.6 64.6 63.6 63.4 55.3 41.1 40.5 36.4 Rhode Island 64.4 64.3 57.5 58.0 58.5 41.2 40.2 40.1 Connecticut 74.2 73.1 69.6 66.9 61.2 46.0 45.2 36.9 New York 64.9 68.5 70.4 74.5 74.6 68.9 67.4 63.8 New Jersey 64.2 65.2 66.1 71.6 75.1 69.6 70.6 68.2
Pennsylvania 57.8 61.5 64.0 67.8 71.9 68.2 68.2 67.1 Midwest 44.8 53.3 60.9 70.4 74.3 73.1 75.4 74.3
Ohio 54.7 61.7 66.6 73.7 78.5 78.5 79.8 78.9 Indiana 39.5 50.3 55.8 68.2 74.2 77.15 79.5 79.2 Illinois 41.9 62.6 74.7 82.5 84.2 84.5 86.2 85.4 Kansas 34.8 50.1 73.8 60.1 69.0 67.4 Michigan 44.0 49.4 50.9 60.1 66.7 67.2 67.7 67.9 Wisconsin 35.1 47.5 50.4 59.7 58.3 56.6 56.5 56.2 Minnesota 17.4 20.5 35.8 54.1 59.6 70.3 71.0 71.1 Iowa 60.5 80.3 83.4 86.5 86.9 85.5
Border South 38.1 39.0 45.4 56.8 61.4 65.8 68.4 68.6
Maryland 60.4 62.1 64.6 65.3 68.9 68.0 66.3 65.9 Delaware 60.8 63.4 66.3 68.5 72.2 70.2 68.7 69.1
KentuCky 35.2 39.9 43.4 49.9 55.2 62.5 64.7 64.7 Missouri 30.2 31.3 42.1 60.1 64.3 67.4 71.1 71.4
Upper South 31.74 32.76 33.5 36.3 41.7 45.6 48.3 51.2 Virginia 39.6 36.8 45.0 42.9 47.8 50.7 50.6 51.0 West Virginia 30.1 37.2 44.1 51.6 55.1 57.7 North Carolina 26.0 27.4 26.5 29.0 34.6 36.6 39.3 41.0 Tennessee 27.3 32.9 34.9 41.1 46.4 50.4 54.3 57.3 Arkansas 24.5 29.8 36.8 41.8 46.4 52.8
Cotton South 29.5 30.8 29.9 32.3 38.9 41.3 47.0 51.5 South Carolina 25.1 28.2 24.9 30.7 39.9 41.3 45.1 49.8 Georgia 28.0 30.3 28.9 31.5 38.0 40.2 45.6 51.3
Mississippi 32.8 32.0 32.1 32.9 39.0 41.6 48.5 51.3 Alabama 36.5 33.4 33.8 33.8 38.8 41.8 46.8 50.5 Louisiana 28.8 29.1 29.1 33.1 39.5 42.2 50.5 56.2
OVERALL NORTH 53.4 57.7 62.6 70.4 72.4 71.7 71.6 70.8 OVERALL SOUTH 32.1 33.3 31.1 39.9 45.6 49.1 53.0 56.0
SOURCE: Census statistics at Geostat Center, University of Virginia Library, http:// fisher.lib.virginia.edu/collections/stats/histcensus/ (hereafter Geostat Center).
525
Agricultural History Fall
percentage of improved land correspondingly increased. The differences between the North and the South, on the other hand, stubbornly per
sisted into the twentieth century. Southerners faired somewhat better when the measure was changed to improved land as a percentage of
total area, even so, the South still trailed far behind the North. The
North-South ratio of improved acreage to total area was 1.47 in 1850,
1.62 in 1860, and 1.72 in 1870. Like Table 1, these results exclude rela
tively unsettled southern states such as Florida, Texas, and Arkansas.
Adding these states would significantly widen the already large regional differences in land-use patterns.4
Land-use patterns might also help explain the high rates of unim
proved land; it is certainly possible that Southerners held large amounts of unimproved land for reasons entirely unrelated to shifting cultivation. Lumber production appears to be the most likely alternative. According to the 1870 census, which broke down unimproved acreage into the
categories of "woodland" and "other," some 80 percent of uncultivated
land on southern farms was forested. While southern farmers undoubt
edly utilized some of their unused woodland for firewood and fencing
northern farmers did the same-unimproved land on southern farms
generally was not used for commercial lumbering. In 1859 the South
produced only 17 percent of the nation's lumber, which suggests that
southern farmers burned, rather than cut, their forests. When the South
became a prominent producer later in the nineteenth century, large
scale lumber camps-not individual farms-became the center of pro
duction, suggesting that shifting cultivation accounted for the large num
ber of unimproved forest lands on southern farms. Planters and farmers
might also have used their unimproved woodlands to feed livestock, but
the value of southern livestock in the antebellum period remained quite low relative to the North. The fact that southern planters let their live
stock forage on low-quality forest growth also indicates shifting cultiva
tion. Cattle grazing on nutritious grasses in improved pastures produced
manure to revitalize fields, but livestock subsisting on poor-quality for
est vegetation provided relatively little in the way of usable fertilizer.5
Plantation journals and travelers' accounts suggest that shifting cul
tivation was widespread in the colonial period; many farmers in both the
North and South used shifting cultivation to rapidly clear land. Whereas most northern farmers eventually made the transition to continuous
526
2007 The Environmental Origins of Shifting Cultivation
cultivation, Southerners generally did not. Seventeenth-century tobacco planter Robert Cole planned his farming operations around the basic fact that after six years "the land had to lie fallow for twenty years
before its fertility returned." As a result, Cole owned a large reserve of land that would be cleared once cultivated fields were exhausted. In the antebellum decades many Chesapeake planters and farmers still utilized what historian Jack Temple Kirby calls "fire culture." Among them was Daniel Cobb, a Southampton County, Virginia, planter who recorded in January 1853 that "I fired a parsel of logs in oald land with 2 hands
where I am going to put Cotton as I wish to rais $250 extry." Shifting
cultivation was quite common in the Lower South as well. Using plan tation journals and other evidence, historian Steven Stoll has docu
mented how planters scarred much of South Carolina through its indis criminate use. Not surprisingly, South Carolina ranked near the bottom in the percentage of improved land throughout the nineteenth century.
When South Carolinians emigrated to the West, they frequently brought shifting cultivation to their new locales. In antebellum Mississippi, his torian John Hebron Moore notes, "wise cotton growers anticipated the destruction of land by acquiring tracts larger than they planned to cul
tivate at the time they were setting up plantations, so that they would
have a reserve of virgin soil to exploit in the future."6
Farmers in southern Appalachia also practiced shifting cultivation, setting fires to clear wooded hillsides and slopes. As was the case in plantation districts, the ash from burnt trees and shrubs effectively fer tilized the land. In many cases, Appalachian farmers let the tree stumps remain, planting their corn in untidy mounds scattered throughout the charred landscape. Although such practices were particularly unsightly, they made ecological sense: the root systems from the deadened trees delayed the onset of soil erosion. Once the fertility of the land was
exhausted either through cropping or erosion-the farmer abandoned the tract to long-term fallow and burned another section of his farm.
This form of shifting cultivation was still practiced in the Ozark Moun tains as late as the 1980s. In contrast to slaveholding planters, who
produced staple crops for national markets, many farmers in western Virginia and other parts of southern Appalachia used shifting cultiva tion to grow corn and wheat for household use and local trade. Higher
transportation costs, which dampened the incentive to produce sur
527
Agricultural History Fall
pluses for eastern markets, undoubtedly discouraged these farmers from adopting continuous cultivation even when they owned relatively more fertile soils.7
Historians have frequently argued that a combination of slavery and
cheap western lands led to shifting cultivation. According to this inter pretation, planters simply "mined the soil" before migrating with their mobile labor force to inexpensive western lands. Other historians have similarly argued that the South's "relative abundance of land and com
paratively high price of labor" created low land prices, which encour
aged shifting cultivation. Still another interpretation posits that South erners, influenced by a Celtic cultural heritage, avoided the hard work of
building barns and improving pastures, preferring instead to let their cattle and swine roam in the woods. Although intuitively appealing, these explanations do not fit all of the available evidence. If cheap land
led to shifting cultivation, why did relatively unsettled states such as Michigan and Wisconsin have a far higher percentage of improved acre
age than Mississippi, Alabama, and Georgia, which contained much of
the nation's most valuable cotton lands?8
Even more importantly, stressing slavery, western lands, or cultural traditions ignores major variations within the South. Significant areas of the South, such as the Kentucky Bluegrass region and the Nashville
Basin, had large plantations, large slave populations, and many at
tributes of the South's distinctive cultural heritage. Planters and farmers
in these regions nevertheless cultivated a higher percentage of land than
even many northern farmers. Planters and farmers in some bluegrass
counties, in fact, often improved more than 80 percent of their land.9
Nature blessed the Kentucky Bluegrass region and the Nashville Ba
sin with rich soils and a temperate climate ideally suited for continuous
cultivation. Most other regions of the South lacked such favorable en
vironmental conditions. Southern soils, as recent studies have suggested, were particularly ill-suited for continuous cultivation. Scientists have classified most of these soils as ultisols, an order characterized by leach
ing, high acidity, and poor fertility. The poor fertility of ultisols helps explain why Southerners burned forest and undergrowth to fertilize
their land. The ash quickly provided important nutrients and its calcium
content helped neutralize acidity. Agricultural reformers highly re
garded ash because its application increased the productivity of soils
528
2007 The Environmental Origins of Shifting Cultivation
lacking "calcareous matters." Given that ash was a cheap, effective fer tilizer-at least before it is leached out of the soil-it is quite expected
that scientists have found a strong correlation between shifting cultiva tion and ultisols in today's developing world.10
The most successful northern cultivators, on the other hand, farmed soils classified as alfisols, which contained an abundance of phosphorus, potassium, calcium, and other essential plant nutrients. Northern farm ers used a highly developed system of mixed husbandry to make the most of their excellent soils. Field rotations usually included clover and other legumes, which added nitrogen to fields depleted by wheat and corn during previous seasons. Cattle grazing in improved pastures, meanwhile, provided tons of high quality manure that recycled key nu trients to maintain the farm's ongoing productivity. Nutrients, however, cannot be recycled unless they are initially present in the soil. That is why the most productive and populous agricultural hinterlands of major northeastern cities-southeast Pennsylvania (Philadelphia), central and western Maryland (Baltimore), and upstate New York (New York City)-all contained significant stretches of alfisol land ideally suited for continuous cultivation."1
In the South, however, alfisol soils were not always associated with continuous cultivation. Substantial portions of Mississippi and Tennes see-two states with fairly low ratios of improved land-contained large
areas of alfisol land. The problem for these areas was topography. Even
the best of soils cannot support continuous cultivation if they are subject to intense erosion, located on inaccessible mountain slopes, or lack proper drainage. Many of the counties along the Mississippi River con tained fairly low percentages of improved land, despite rich alluvial soils, because frequent flooding inhibited cultivation. Erosion prevented in tensive farming practices in the fertile Black Belt of Mississippi and Alabama, where row cropping created channels that carried away valu able top soil. Erosion was particularly severe in these areas because of
the South's unique rainfall patterns. Soil erosion experts have developed a "Rainfall and Runoff Factor" (R-factor) to measure the intensity and
duration of storms. The higher the R-factor, the more likely that local
rainfall will intensify soil erosion. The Southeast has the highest R-factor of the nation, with the intense, pelting storms of the Gulf Coast states
creating a particularly high rate of soil erosion.12
529
Agricultural History Fall
Southern farmers suffered other disadvantages as well. Key fodder crops, such as hay and clover, that supported continuous cultivation could not thrive in the warm and humid southern climate. Southern
planters and farmers fed their cattle the best they could, most often with
cow peas and low-quality grasses, but the relatively low nutritional value
of such feed meant southern cattle produced far less dung than northern
cattle. The warm southern climate also created a hospitable environ
ment for the ticks that spread bovine babesiosis, also known as southern
cattle fever or Texas fever. Southern cattle exposed to such infections at
an early age developed immunity to the worst effects of the disease.
Southern cattle fever, however, prevented Southerners from improving the quality of their animals because high-quality breeds from Europe or
the North-without immunity-quickly succumbed to the disease. Southern cattle thus lagged behind northern livestock in terms of weight and milk production. Under these adverse conditions, most southern agriculturalists devoted little time and energy to tending to their live stock. Continuous cultivation posed far more difficulties without thriv ing livestock that could efficiently recycle key nutrients.13
To statistically test the importance of soils, climate, and disease, we
estimated a series of county-level regressions in which the dependent variable is the percentage of improved land for 1860 (Table 2). Our
independent variables (on the left side of the table) classify every county in eight southern states according to soil type, topography, and level of
economic development. For soil type, we used data from the State Soil
Geographic Database-STATSGO-to determine if alfisols were the
primary soils of a county or at least important secondary soils. Out of
698 southern counties, 110 counties contained mostly alfisol soils, while another 232 contained smaller stretches of alfisols. To capture the im
pact of topography, we grouped southern counties into seven major geographical areas (please see the appendix). We also included a vari
able to account for counties that most likely suffered from Texas fever.14
Most of our independent variables are dummy variables that are
basically "yes" or "no" responses to a particular question. For the rail
.,road variable, for example, a county with a railroad receives a value of
1 (a statistical "yes"), while a county without a railroad receives a value
of 0 (a statistical "no"). The coefficient is the impact of a "yes" response.
To use the railroad variable as an example, the coefficient reported in
530
2007 The Environmental Origins of Shifting Cultivation
Table 2. Determining the Percentage of Improved Land: County-Level Regression Results for Nine Southern States, 1860
Variable or Geography Addition of RRs Addition of Diagnostic Statistic and Climate and Cities Crop Choice
Intercept (Piedmont Counties) 39.7** (31.57) 37.7** (29.2) 34.02** (23.48)
Coastal Flatwoods -19.3** (-8.96) -18.7** (-8.78) -15.0** (-7.16) Coastal Plain -6.9** (-4.76) -6.39** (-4.48) -6.1** (-4.42) Mountains and Ridges -16.4** (-11.51) -15.3** (-10.70) -13.5** (-9.41) Hills and Valleys -11.8** (-6.50) -10.6** (-5.91) -7-53** (-4.21) Miss. Alluvial and
Black Prairies -9.0* (-4.23) -8.71** (-4.20) -9.27** (-4.49) Limestone Basins 15.8** (7.49) 16.3** (7.84) 18.23** (9.01)
Primary Alfisol 12.3** (7.72) 10.9** (6.84) 10.02** (6.55)
Secondary Alfisol 4.2** (2.75) 3.74** (3.49) 3.2** (3.11) Southern Cattle Fever -4.2** (-3.88) -4.0** (-3.08) -5.4** (-4.21) Railroad County 5.31** (5.05) 3.8** (3.80) Urban County - 0.01 (0.30) 1.8 (0.73) Wheat - 8.10** (6.74) Cotton 8.99** (6.30) Tobacco -1.3 (-0.07) Adjusted R-Squared 0.476 0.500 0.556 F-Statistic 71.29 63.13 61.19 Degrees of Freedom 688 686 683
*Significant at 5 percent level **Significant at 1 percent level
Dependent Variable: Percentage of Improved Land in Farms at the County Level, 1860
(t-statistics in parentheses). SOURCE: Census statistics at the Geostat Center. Soil orders classified using Soil Survey
Staff, Natural Resources Conservation Service, USDA, "US General Soil Map (STATSGO)," http://soildatamart.nrcs.usda.gov (hereafter STATSGO). Please see the appendix for topographical classifications. We classified most counties in Mississippi, Ala bama, Georgia, and South Carolina as southern cattle fever counties.
Table 2 is 5.3, which means that a railroad added 5.3 points to a county's
percentage of improved land. A county without a railroad that culti
vated 40 percent of its improved land, in other words, would have cul
tivated 45.3 percent of its land if a railroad had been built. The result
suggests that railroads made commercial agricultural more feasible, thus encouraging farmers and planters to cultivate more land. Regression analysis is so valuable because it holds the impact of all the specified
531
Agricultural History Fall
variables constant. In this case, the coefficient of the railroad variable
measures the impact of railroad access after taking into account soil
type, topography, urbanization, and crop choice. The regression results highlight the powerful impact of environmen
tal factors on levels of improved land. Counties primarily composed of alfisols, in fact, added 10 to 12 percentage points to the percentage of
improved land. The effect for counties that contained only partial strips of alfisols, not surprisingly, was somewhat less than for counties com
posed primarily of alfisols, but both variables were statistically signifi cant. As for topography, the limestone basins, which include the Ken
tucky Bluegrass region and the Nashville Basin, contained a higher per
centage of improved land than the other areas. A limestone county, on
average, had 15 to 16 more percentage points of improved land than the
typical Piedmont county. The large negative coefficient for the Coastal Flatwoods-an area well known for its pine barrens and poorly drained
marshlands-is particularly striking because many of the South's largest port cities were located in that region. The negative coefficient for the
Texas fever variable is also statistically significant, suggesting that live stock disease made continuous cultivation far more difficult in the Cot
ton South. Since the ticks that carried babesiosis thrived in heat and
humidity, this variable could also be picking up the negative impact of
the Deep South's climate on fodder crops and improved pastures. The
ticks within one hundred miles of the Gulf Coast-known as Rhipi
cephalus microplus (previously known as Boophilus microplus)-were more pernicious than Rhipicephalus annulatus (previously known as Boophilus annulatus) ticks that infected the rest of the South, which may
have worsened the large, negative coefficients for the coastal flatwoods
and coastal plain variables. Taken all together, the environmental vari
ables seriously suggest that the southern climate and geography directly
resulted in shifting cultivation.15 In contrast, two indicators of general economic development-the
presence of railroads and cities over five thousand residents-had a
relatively small impact on levels of improved land. The railroad variable
is positive and statistically significant, suggesting that better transporta tion opened markets, which encouraged farmers to improve more land.
Yet the small size of the coefficient, 3.8-5.3 percentage points, depend
ing on the specification, indicates that railroads had far less impact than
532
2007 The Environmental Origins of Shifting Cultivation
environmental variables. For cities, there was no statistically significant relationship between urbanization and the percentage of improved land after controlling for other factors. This comprised a major difference between the North and the South. The North's vibrant urban and manu facturing sector, as well as its rapidly improving transportation network, created larger markets for farmers, which gave them a greater incentive to improve more land. A self-reinforcing dynamic emerged in which intensive cultivation encouraged urban growth and transportation im provements, thus allowing farmers to improve an even higher percent age of their land. Some antebellum observers argued that more manu facturing and urban growth in the South would eventually foster more intensive cultivation practices, but such prescriptions failed to recognize the severity of geographic and climatic restraints in the South.16
The low level of improved land within urban counties demonstrates the tenacity of these environmental constraints. In 1860 twenty-seven southern counties had cities with a population greater than five thou sand people. The percentage of improved land within these urban coun ties barely budged in the 1850s-moving from 34.5 percent to 37.3 per cent-and remained far below national averages. In the nine counties containing the South's major port cities, including Norfolk, Charleston, and New Orleans, planters and farmers cultivated less than 20 percent of their land. These statistics confirm the regression results showing that urbanization made no impact in determining levels of improved land. Historian Ulrich B. Phillips made a similar point in regards to Charles
ton more than a century ago: "To maintain Charleston's commercial
eminence, nothing would suffice, in fact, but to make the wilderness behind her blossom; but railways and all things else have thus far failed
to convert the pine-barrens into any semblance of a garden."17
Some historians have maintained that southern staples, such as cot ton, tobacco, and corn, depleted the land more rapidly than wheat and
other crops that were more likely to be grown in the North. To test this
proposition, we included dummy variables representing counties in the top quartile of wheat, cotton, and tobacco production. The wheat vari
able has a statistically significant and relatively large coefficient, which suggests that grain farmers in Virginia and other areas of the Upper
South were more likely to integrate livestock and crops into a mixed
farming regime. The argument that the special characteristics of cotton
533
Agricultural History Fall
and tobacco accounted for shifting cultivation, however, receives little
support. Cotton, in fact, was associated with more, not less, improved land. The large coefficient for the cotton variable indicates that planters
brought more marginal land into cultivation in response to the high
prices of the 1850s. Notice that even with the inclusion of the crop choice variables that almost all of the coefficients of the geographic and
climatic variables remain statistically significant.18
However, the analysis thus far has ignored a vitally important ques tion: what about the relationship between slavery and shifting cultiva
tion? As a first step to understanding the impact of slavery, Figure 1
1.2 . .......... ~
0.8 ..*... ...,... .
4 ~~~~~~~~~~~~~~4 ,
4 .,s~~~~~. 4 ~
WO:W 0.4~~~~~~~~"4
L. 4~~~~~~~~~~~.... .. 0 44~~~~~~~ 024 '?~~*~* 4'vc.'.. W44'', ~~~~~~~ -~ ~~~~~~~~~.... .
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Percent Enslaved
Figure 1. The Relationship Between Slavery and the Percentage of Improved Land in
Farms, 1860. Source: Calculated from census statistics at the Geostat Center.
charts the percentage of improved land and the percentage of the en
slaved population for each county. On the bottom left-hand corner there
is a large clustering of counties with both a low percentage of improved land and a low percentage of slaves. Almost all of these counties, not
surprisingly, were located in the mountainous upcountry. In the middle
of the graph are counties with intermediate to high percentages of slaves
and intermediate to high levels of improved land, including counties in
the Alabama and Mississippi Black Belt, the southern Piedmont, and the
limestone areas. Levels of "intermediate" and "high," of course, are
based only in relation to the South; planters in many of these counties
534
2007 The Environmental Origins of Shifting Cultivation
improved less land than most northern farmers. Located on the bottom right-hand corner is a smaller group of counties with high concentrations of slaves but low levels of improved land. Most of these counties were located along the coast of the Carolinas and Georgia, where rice plant ers intensively cultivated a small number of acres and left most of their poorly drained "provisioning" lands unimproved. Overall, Figure 1 in dicates that antebellum slavery was a flexible institution suitable for both shifting cultivation and continuous cultivation.
Ideally, we would econometrically test the relationship between sla very and levels of improved land in a regression that holds soil quality, topography, and climate constant. When slavery is inserted into the equations in Table 2, the coefficient shows a strongly positive-and statistically significant-relationship with higher levels of improved land. Simply put, counties with more slaves contained more improved land when all other environmental and economic variables are taken into account. Adding slavery to the regressions, though, is bedeviled with what econometricians call an endogeniety bias. To put it simply, it is impossible to tell with county-level data whether slavery caused more land to be improved or whether slaveholders simply preferred to locate in areas with the best soils and best access to transportation. We have
run statistical tests to correct the endogeniety bias, but they do not work well given the limitations of census data.19
The non-linear relationship between slavery and levels of improved land increases our skepticism about the econometric evidence. It makes little sense to suppose that the lack of slave labor was a major reason for
low levels of improved land in the southern uplands; likewise, it seems unlikely that Carolina rice planters improved a small percentage of their land because they somehow possessed too many slaves. Our interpre tation of the evidence, then, is that the slavery coefficient reflected underlying environmental conditions, rather than acting as an important variable in its own right.20
Although little direct evidence exists on this point, it is certainly possible that slavery and cheap western lands discouraged Southerners from finding sustainable alternatives to shifting cultivation. With a bound labor force available to clear land, slaveholders had less incentive
to develop fertilizers, find suitable fodder crops, or combat southern cattle fever. The same logic holds true of inexpensive western land; it did
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not cause shifting cultivation per se, but it certainly might have discour aged efforts to find alternatives. Although agricultural reformers in older, eastern seaboard states worried about the developmental conse quences of shifting cultivation, planters only intermittently supported long-term agricultural research. Southern state legislatures hesitated to spend even small sums on basic geological surveys, and they often re
fused to subsidize experimental farms, agricultural professorships, and research stations. Many planters belonged to state and local agricultural societies, which made headway in developing marl (a mix of clay and
fossilized seashells) and other fertilizers that provided the soil with cal cium, thereby reducing its acidity. Marl and associated fertilizers, though, were risky and expensive. As frustrated agricultural reformers like Edmund Ruffin noted, planters making substantial profits using shifting cultivation had little economic incentive to use marl or other
means of reducing soil acidity. Why adopt continuous cultivation when highly mobile planters and their slaves could use shifting cultivation to quickly convert new land into workable plantations?21
In the postbellum era, the continued development of the railroad
network-combined with greater investment in agricultural research gradually raised the percentage of improved land on southern farms.
The region's railroad network expanded dramatically after the Civil
War; 90 percent of the southern population lived in a county that had a
least one railroad station by 1890. The quality of rail service also im
proved as large trunk lines integrated individual lines into coherent
networks with standardized gauges. The expansion of the region's rail
road network contributed to a dramatic increase in urbanization, par
ticularly in upland areas that had been relatively isolated before the
Civil War. Within agriculture itself, phosphate emerged as a relatively
inexpensive fertilizer for southern planters and farmers. Federal and state experiment stations provided advice and technical support about fertilizers and other cultivation practices for those wishing to adopt
more intensive agriculture. In light of these changes, shifting cultivation
gradually declined and the percentage of improved land within southern farms gradually increased between 1880 and 1920 (Table 1). By the turn
of the century, Southerners improved a higher percentage of their land
than farmers in New England, where a sharp drop in wool prices led
farmers to abandon many of their improved pastures.22
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2007 The Environmental Origins of Shifting Cultivation
These important technological developments and institutional changes, however, did not suddenly sweep aside the South's severe en vironmental constraints. The regional differences in land-use patterns remained, as farmers in the cotton states still lagged far behind their
mid-Atlantic and midwestern counterparts. In 1920 farmers in North Carolina, South Carolina, Georgia, Alabama, Mississippi, and Louisi ana-despite the spread of railroads, the growth of cities, and the in
troduction of new fertilizers-still cultivated a lower percentage of their land than Ohio farmers had in 1850. Advocates of continuous cultivation within the South, according to historian Gilbert Fite, often expressed keen disappointment at the slow rate of progress. Fite attributes the southern failure to fully adopt continuous cultivation to ingrained tra ditionalism and the South's reliance on cotton, but he also notes that
environmental factors continued to hinder progress:
The natural grasses and forage in much of the South were less nutri
tious than those found in the Midwest. To get satisfactory pastures and
hay in the Deep South the soil had to be plowed, planted, and fertil
ized at considerable expense.... In addition, southern livestock was
subject to diseases that caused heavy losses. Swine and fowl cholera
were common, and Texas fever became so widespread that in the early
1880s it was being referred to by a veterinarian in the USDA as
"Southern Cattle fever."23
Regression analysis for 1890, using many of the same variables as the
1860 specifications, confirmed Fite's observations (Table 3). Initial soil quality, despite the introduction of cheaper fertilizers, still had a signifi
cant impact. Counties composed mostly of alfisols continued to improve
10-12 percent more land than counties possessing ultisols or other soils.
The coefficients for the 1890 topographical variables generally remain statistically significant and have the same signs as those in the 1860
regressions. Farmers on limestone plains continued to cultivate a far
higher percentage of their land than farmers living in other topographi
cal regions, while the marshy Coastal Flatwoods lagged especially far
behind. Texas fever, which had spread to several areas in the Upper
South during the Civil War, grew even worse in 1890. Farmers in coun
ties with babesiosis cultivated 8 to 12 percent less land after taking into
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Table 3. The Continuing Importance of Environmental Factors in the Postbellum Era: County-Level Regression Results for Nine
Southern States, 1890
Variable or Geography Addition of RRs Addition of Diagnostic Statistic and Climate and Cities Crop Choice
Intercept (Piedmont Counties) 50.6** (32.0) 45.0** (25.2) 43.2** (22.8)
Coastal Flatwoods -19.6** (-9.4) -19.5** (-9.7) -15.2** (-7.3) Coastal Plain -7.4** (-5.1) -6.6** (-4.6) -4.7** (-3.2) Mountains and Ridges -12.5** (-7.9) -11.5** (-7.44) -9.5** (-6.0) Hills and Valleys -5.5** (-2.8) -4.6** (-2.6) -3.9* (-2.2) Miss. Alluvial and
Black Prairies -2.0 (-0.9) -1.9 (-0.9) -4.2* (-2.15) Limestone Plains 16.6** (7.9) 15.5** (6.8) 16.5** (7.5)
Primary Alfisol 13.3** (8.4) 11.6** (7.4) 11.4** (7.5)
Secondary Alfisol 3.2** (3.0) 2.6** (2.5) 2.5* (2.4) Southern Cattle Fever -7.9** (-6.5) -9.2** (-7.6) -12.0** (-9.5) Railroad County 6.9** (5.6) 6.68** (5.6) Urban County 6.6** (4.1) 7-7** (4.8) Wheat 1.4 (1.2) Cotton 9.8** (7.5) Tobacco 0.8 (0.71) Adjusted R-Squared 0.48 0.52 0.55 F-Statistic 81.3 75.8 67.9 Degrees of Freedom 766 764 761
*Significant at 5 percent level
**Significant at 1 percent level
Dependent Variable: Percentage of Improved Land in Farms at the County Level, 1890
(t-statistics in parentheses). SOURCE: Census statistics at the Geostat Center. Soil orders classified using STATSGO. Please see the appendix for topographical classifications. Counties with southern cattle
fever classified according to Bureau of Animal Industry, Map Showing Boundary Line of
District Infected with Splenetic or Southern Cattle Fever, as Defined in Order of Hon. J. M.
Rusk, Secretary of Agriculture (Washington, DC: GPO, 1891).
account other variables. In Virginia, for example, the percentage of
improved land in twenty-three newly infected counties declined from 44 percent to less than 40 percent between 1860 and 1890, whereas the
percentage of improved land within the state as a whole increased from
37 percent to 48 percent.24
In contrast to the 1860 results, the regressions show that cities and
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2007 The Environmental Origins of Shifting Cultivation
railroads in the 1890s significantly influenced land-use patterns. In 1860 railroads and cities had only a small impact on the percentage of im
proved land, but by 1890 farmers in a county with a railroad connection and a city improved nearly 14 percentage points more land than their non-railroad, non-urban counterparts. What accounts for this change? Southern railroads and urbanization before the Civil War had focused on linking plantation districts to port cities. The postbellum extension of the rail network to the southern uplands, working in conjunction with increased urbanization, seems to have "unlocked" high quality alfisol soils in Appalachia. Indeed, the percentage of improved land between 1860 and 1890 increased faster in the southern uplands than any other region. Notice, too, that the dummy variable representing a county in the top quartile in cotton production is statistically significant. The con tinued expansion of the South's cotton culture might well have incor porated previously marginal acreage that had gone unimproved. The completion of levees on the Mississippi, in particular, created rich new land for cotton in the Black Belt. Within the state of Mississippi, for example, farmers and planters in the eleven counties bordering the river increased the percentage of improved land from 36 percent in 1860 to 52.5 percent in 1890, a rate of increase far greater than the South as a
whole.25 The use of cheap phosphate fertilizers represented another important
change in the postbellum period. To what extent did these fertilizers increase the percentage of improved land? Data from the 1890 census shows that farmers in the Coastal Flatwoods, Piedmont, and coastal plains spent significantly more on fertilizer than the South's other to pographical regions: eighty-nine cents, forty-nine cents, and thirty cents per improved acre, respectively, compared to a combined average of eighteen cents. All of the areas that relied on phosphate fertilizers also cultivated relatively low levels of improved land. The correlation be tween low levels of improved land and fertilizer usage is hardly surpris ing. Farmers with the worst soils, and hence the lowest levels of im proved land, might have been more likely to use fertilizers than farmers working the best lands. Phosphates, in fact, may well have prevented complete disaster in the piedmont and coastal flatwood regions. Because of increased erosion and competition from more fertile regions, farmers in these areas might have cultivated less land, in absolute terms, in 1890
539
Agricultural History Fall
than in 1860 without the use of artificial fertilizers. As it was, the struggle to achieve even modest increases in improved acreage with the most advanced fertilizers shows how the struggle to conquer nature was still incomplete in 1890.26
Our evidence suggests that southern farmers and planters utilized shifting cultivation because of difficult environmental conditions. From the standpoint of an individual planter or farmer, shifting cultivation
worked reasonably well as long as there was enough reserve land. Hav
ing large tracts of unimproved land in reserve, though, posed a major impediment to southern development. Shifting cultivation, in essence, created huge swaths of economic "dead space" that generated little or
no economic activity. Adding unimproved acres meant larger farms and larger plantations without increasing the size of the workforce, thus reducing population densities. One of the overlooked facts of the ante bellum period is that the South trailed far behind the North not only in
overall population density, but rural population density as well. In 1860,
for example, the South Atlantic region-Virginia, North Carolina,
South Carolina, and Georgia-contained 20.3 total rural residents per
square mile and 11.7 free rural residents per square mile, far behind New
England (33 rural residents per square mile), the Middle Atlantic states
(49 rural residents per square mile), and the Old Northwest (35 rural
resident per square mile). The impact of shifting cultivation in dispersing rural populations was well understood, even for the colonial period. "By
the middle of the eighteenth century," writes historian T. H. Breen,
"most [Virginia] planters accepted that dispersed settlement was an
inevitable product of a particular type of agriculture." In the North, low
population density in rural areas was a temporary phenomenon associ
ated with recent settlement. In the South, shifting cultivation created the
demographic equivalent of a permanent frontier in which vast amounts
of land remained uncultivated every generation.27 A number of scholars have noted how the southern economy gener
ated far smaller markets for manufactured goods and urban services,
thus hindering the growth of industry and cities. In the North, continu
ous cultivation created a prosperous and deeply rooted rural population
that helped stimulate early industrialization. As population increased
and transportation improved, manufacturing firms competing in larger
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2007 The Environmental Origins of Shifting Cultivation
markets had greater incentives to expand output and improve produc tivity. Dense networks of farms in southern New England, upstate New York, and southeastern Pennsylvania provided particularly rich markets for manufactured goods. These local markets spurred manufacturing in cities such as New York and Philadelphia. The chapter titles of David R. Meyer's recent synthesis of early northern industrialization-"Prosper ous Farmers Energize the Economy" and "Agriculture Augments Re gional Industrial Systems"-testify to the importance of deep and rich rural markets to northern manufacturers.28
In sharp contrast, scholars have used the term "disarticulation" to describe a southern economy that lacked market towns and local manu facturing. It seems reasonable to suppose that shifting cultivation, along with slavery, contributed to the small size of southern markets. Recall that farmers and planters even near relatively large cities such as Nor folk and Charleston cultivated less than 20 percent of their land. Lacking nearby markets, southern ports specialized in the collection and expor tation of staple crops and supported a modest manufacturing base rela tive to northern cities.29
Low population densities also made it more difficult for Southerners to create institutions to cultivate and disseminate productive knowledge.
A region composed of isolated farms and plantations generated fewer subscribers for periodicals and newspapers, possessed fewer potential members for mechanics institutes or literary associations, and provided fewer students for schools and colleges. Economic historians have found a strong correlation between low population density and illiteracy in the antebellum period, whether one considers the North or the South. In the North, low population density in rural areas was temporary, whereas in
the South it became the norm.30 The South, as many historians have noted, remained behind the
North in literacy rates, schools, libraries, and other indicators of educa tional achievement. Southerners themselves often felt overly dependent on northern newspapers and literature; calls for an authentically "south ern" literature became commonplace in the antebellum period. Cultural and political factors-including racism and anti-democratic attitudes undoubtedly contributed to southern backwardness in education and the
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Agricultural History Fall
arts, but the combination of slavery and shifting cultivation decreased the number of possible readers for southern newspapers, periodicals, and books, thus making the publication of such works even more diffi
cult.31
Northerners noticed the impact of shifting cultivation on southern society. To Northerners, southern agriculture lacked the order and re finement that characterized their neat and carefully maintained farms. The unsightly nature of southern farms and plantations-the recently burnt fields, the seemingly endless forests of pine, and the shockingly neglected livestock-all accentuated the region's relative lack of devel opment. The South's uncultivated landscape and dispersed population created a ramshackle air about the region; its public buildings seemed less impressive, its farms and plantations less permanent, and its com
munity institutions (including libraries, schools, and churches) less de veloped. For Northerners who believed in the economic and moral su periority of free labor-what historians have called free-labor ideol
ogy-the desultory state of southern agriculture and the region's general
underdevelopment became a powerful indictment of slavery. The lazi
ness that seemed to pervade southern agriculture provided compelling evidence that slavery devalued hard work and suppressed the spirit of enterprise. During the Missouri Crisis of 1819-1820, New York Con gressman John Taylor, for example, emphasized the differences across
the border between Maryland and Pennsylvania:
the dividing line between farms highly cultivated and plantations lay
ing open to the common and overrun with weeds; between stone barns
and stone bridges on one side, and stalk cribs and no bridges on the
other; between a neat, blooming, animated, rosy-cheeked peasantry on the one side, and a squalid, slow-motioned, black population on the
other.32
No writer solidified the northern view of southern agriculture and its impact on slavery more than Frederick Law Olmsted. As a landscape
architect-he would go on to design New York City's Central Park
Olmsted had an eye for telling detail as he traveled through the South
in the 1850s. When in Tidewater Virginia, he famously noted that "'old
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2007 The Environmental Origins of Shifting Cultivation
fields'-a coarse, yellow, sandy soil, bearing scarce anything but pine trees and broom-sledge" dominated the countryside. Olmsted became lost along the poorly marked roads and isolated homesteads. Getting directions was almost impossible, and Olmsted reported that one was more likely to see gangs of wild hogs, "long, lank, bony, snake-headed, hairy, wild beasts," than people when traveling through the pine forests of the state. The only dwelling that he passed was "a house, across a
large, new old-field . . . there was no distinct path leading towards it out
of the wagon-track we were following." When he finally reached "the Court House," the local designation for the county seat, he noted that it consisted of thirty or so buildings, including several stores, a law office, a saddler's shop, and two public houses. For the hub of local commerce, "the Court House" was slim pickings indeed.33
In line with current historical theory, Olmsted blamed slavery for shifting cultivation. Like other antebellum writers, he conflated the abil ity to grow staple crops such as cotton, tobacco, rice, and sugar with fertile soils and a hospitable climate. The reality was far different. In the
long run, the South's soils, climate, and topography prevented intensive agriculture and slowed long-term development. Shifting cultivation was not the sole cause of southern underdevelopment, though. While slavery did not create shifting cultivation, it may well have accentuated the developmental consequences of the land-hungry agricultural regime. A number of scholars have argued that slaves consumed little in the way of
manufactured goods or urban services, thus contributing to the limited
nature of southern markets. Slavery, in essence, accentuated the "lack of demand" that hurt southern industry and commerce. Our brief and suggestive analysis of shifting cultivation's economic impact indicates that historians and other scholars might well see slavery and shifting
cultivation working together to create an economy with low population densities, little manufacturing, and low levels of urbanization. Slavery, of course, also made it even more difficult to support educational institu
tions. Slaves could not subscribe to newspapers, join voluntary organi
zations, or attend schools. Rather than approach the question of south
ern underdevelopment in dichotomous terms-either the "environ ment" or "institutions" (slavery)-future research should fruitfully focus on the interaction of the two.34
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Agricultural History Fall
Appendix: Explanation of Topographical Variables
Southern Piedmont: Acting as the intercept, this region supported a mix of soils and landscapes that was generally favorable to agriculture but nevertheless susceptible to erosion.
Coastal Flatwoods: Generally infertile region dotted with pine barrens and marshes.
Coastal Plain: Highly variable region between the coastal flatwoods and piedmont regions.
Mountains, Valleys, and Ridges: Includes counties within the Cumber land Plateau, Appalachian Plateau, Appalachia Hill and Ridge re gion, and Blue Ridge Mountains. Soil quality is variable, but steep slopes and narrow valleys posed severe erosion problems.
Hills and Valleys: Includes the Pennyroyal region, Sandstone and Shale Hills, Sand Hills, and Fall Line Hills. Variable in terms of soil drain age and erosion.
Limestone Plains and Valleys: Includes the Bluegrass region of Ken tucky, the Nashville Basin of Tennessee, and the northern Shenan doah Valley of Virginia. All are well-drained landscapes ideal for continuous cultivation.
Mississippi Alluvial and Black Prairies: Includes Mississippi Alluvial
Valley, Mississippi Valley Silty Uplands, Mississippi Black Belt, and Alabama Black Belt. These were the premier cotton-growing regions of the Lower South, but often poorly drained and subject to severe erosion.
NOTES
1. We would like to thank Jarad Beckman for excellent research assistance. For com
ments on earlier drafts, we thank Jay Carlander, Dennis Halcoussis, Jeff Hummel, Lisa
Jacobson, Naomi Lamoreaux, Jean-Laurent Rosthenthal, Roger Ransom, Ken Sokoloff, Gavin Wright, and the participants of the Von Gremp Workshop in Economic History at
UCLA and the All-UC Economic History Group Conference on agricultural history at
Davis, Calif. We also benefited from the comments of three referees.
Farm Journal of Julian Ruffin, Ruf fin Papers, Mssl:R838a 818, Virginia Historical
Society, Richmond, Va. On Ruffin's continued use of shifting cultivation, see, Jack Temple
Kirby, Poquosin: A Study in Rural Landscape and Society (Chapel Hill: University of
North Carolina Press, 1995), 111.
2. Shifting cultivation in the South often had a pronounced commercial orientation in
which planters produced cotton and tobacco for international markets. The southern
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2007 The Environmental Origins of Shifting Cultivation
variant is thus somewhat different than the shifting cultivation regimes used in the tropics
today, where it is used "for producing basic foodstuffs and meeting subsistence and local
market needs." National Research Council, Sustainable Agriculture and the Environment
in the Humid Tropics (Washington, DC: National Academy Press, 1993), 78.
3. For discussions of shifting cultivation, see, Ulrich B. Phillips, Life and Labor in the
Old South (Boston: Little, Brown, and Company, 1929), 9,136; Lewis Cecil Gray, History
of Agriculture in the Southern United States to 1860, Vol. 1 (Gloucester, Mass.: Peter Smith,
1958), 448; Paul W. Gates, The Farmer's Age: Agriculture, 1815-1860 (New York: Harper & Row, 1960), 112-13; Julius Rubin, "The Limits of Agricultural Progress in the Nine
teenth-Century South," Agricultural History 49 (Apr. 1975): 362-73; Douglas Helms, "Soil
and Southern History," Agricultural History 74 (Fall 2000): 723-58; Steven Stoll, Larding the Lean Earth: Soil and Society in Nineteenth-Century America (New York: Hill and
Wang, 2002); and Kirby, Poquosin, 95-125. Phillips, Rubin, Helms, and Kirby generally
provide geographic and climatic explanations for shifting cultivation, while Gates, Gray, and Stoll generally focus on slavery, western lands, and southern traditionalism.
4. Improved and unimproved acreage taken from census data available at Geostat
Center, University of Virginia Library, http://fisher.lib.virginia.edu/collections/stats/ histcensus/ (hereafter Geostat Center). According to special instructions to the 1860 cen
sus, marshals were to exclude "irreclaimable marshes" and large bodies of water from total
acreage. Jeremy Atack and Fred Bateman, To Their Own Soil: Agriculture in the Ante
bellum North (Ames: Iowa State University Press, 1987), 118-19.
5. The South's share of lumber production was calculated from census statistics found
in J. M. Edmunds, Manufactures of the United States in 1860: Compiled from the Original Returns of the Eighth Census, Under the Direction of the Secretary of the Interior (Wash
ington, DC: GPO, 1865), 682, 695, 708, 716. On lumber production in the postbellum
period, see, Edward L. Ayers, The Promise of the New South: Life After Reconstruction
(New York: Oxford University Press, 1992), 124-25. On the relatively poor quality of
southern forage and livestock, see, John Hebron Moore, The Emergence of the Cotton
Kingdom in the Old Southwest: Mississippi, 1770-1860 (Baton Rouge: Louisiana State
University Press, 1988), 26-27; Stoll, Larding the Lean Earth, 82-83.
6. Lois Green Carr, Russell R. Menard, and Lorena S. Walsh, Robert Cole's World:
Agriculture and Society in Early Maryland (Chapel Hill: University of North Carolina
Press, 1991), 39; Allan Kulikoff, Tobacco and Slaves: The Development of Southern Cul
tures in the Chesapeake, 1680-1800 (Chapel Hill: University of North Carolina Press,
1986), 48; Kirby, Poquosin, 95-125; Daniel W. Crofts, ed., Cobb's Ordeal: The Diaries of a Virginia Farmer, 1842-1872 (Athens: University of Georgia Press, 1997), 71. According to Crofts, "Cobb replicated patterns of slash-and-burn agriculture that had been practiced in Virginia long before the arrival of Europeans" (64). Stoll, Larding the Lean Earth,
120-66; Moore, The Emergence of the Cotton Kingdom in the Old Southwest, 86.
7. J. S. Otto and N. E. Anderson, "Slash-and-Burn Cultivation in the Highlands South:
A Problem in Comparative Agricultural History," Comparative Studies in Society and
History: An International Quarterly 24 (Jan. 1982): 141-42. On the farmers of the southern
upcountry, see, Harry L. Watson, "Slavery and Development in a Dual Economy: The
South and the Market Revolution," in The Market Revolution in America: Social, Political,
and Religious Expressions, 1800-1880, ed. Melvyn Stokes and Stephen Conway (Char lottesville: University Press of Virginia, 1996), 43-73.
545
Agricultural History Fall
8. For a recent statement of this view, see, Roger G. Kennedy, Mr. Jefferson's Lost
Cause: Land, Farmers, Slavery, and the Louisiana Purchase (New York: Oxford University
Press, 2003), 11-25. See, also, Gray, History of Agriculture in the Southern United States,
448; John Solomon Otto, Southern Agriculture During the Civil War Era, 1860-1880
(Westport, Conn.: Greenwood Press, 1994), 4-6; Grady McWhiney, Cracker Culture:
Celtic Ways in the Old South (Tuscaloosa: University of Alabama Press, 1988), 51-79.
9. Census marshals, in fact, reported no unimproved land in Bourbon and Clark coun
ties, part of the heart of the Kentucky Bluegrass. Census data is available at the Geostat
Center. For more on the Kentucky Bluegrass and Nashville regions, see, Stephen Aron,
How the West was Lost: The Transformation of Kentucky from Daniel Boone to Henry
Clay (Baltimore: Johns Hopkins University Press, 1996), 124-49; Helms, "Soil and South
ern History," 733-34; Phillips, Life and Labor, 80-83.
10. For excellent explications of the many problems of ultisols, see, S. W. Buol et al.,
Soil Genesis and Classification (Ames: Iowa State University Press, 1997); Helms, "Soil
and Southern History"; National Research Council, Sustainable Agriculture, 53-57. On the
fertilizing properties of ash, see, Kirby, Poquosin, 111-14; "Leached Ashes as a Manure,"
Southern Agriculturalist (Sept. 1841): 479-80; Henry D. Foth and John W. Schaffer, Soil
Geography and Land Use (New York: John Wiley & Sons, 1980), 179.
11. On the importance of livestock to intensive land use among northern farmers, see,
Donald H. Parkerson, The Agricultural Transition in New York State: Markets and Mi
gration in Mid-Nineteenth-Century America (Ames: Iowa State University Press, 1995),
94-98; Stoll, Larding the Lean Earth, 49-54.
12. Moore, Emergence of the Cotton Kingdom, 31-34; Phillips, Life and Labor, IS, 11,
102-103; Walter H. Wischmeier and Dwight D. Smith, Predicting Rainfall Erosion Losses:
A Guide to Conservation Planning, USDA Handbook No. 537 (Washington, DC: USDA,
1978), 5-6; Stanley Wayne Trimble, Man-Induced Soil Erosion on the Southern Piedmont, 1700-1970 (Ankeny, Iowa: Soil Conservation Society of America, 1974), 12-13; Stoll,
Larding the Lean Earth, 134-43.
13. Tamara Miner Haygood, "Cows, Ticks, and Disease: A Medical Interpretation of
the Southern Cattle Industry," Journal of Southern History 52 (Nov. 1986): 551-64; Claire
Strom, from a forthcoming book manuscript tentatively entitled "Making Cat Fish Bait out
of Government Boys: Politics, Class, and Environment in the New South," 1-15, in pos session of author.
14. Our eight southern states include Virginia, Kentucky, Tennessee, North Carolina,
South Carolina, Georgia, Alabama, and Mississippi. We excluded all states west of the
Mississippi, as well as Florida. The 1890 table includes West Virginia as well. Soil Survey
Staff, Natural Resources Conservation Service, USDA, "US General Soil Map
(STATSGO)," http://soildatamart.nrcs.usda.gov. We classified all counties in Alabama,
Mississippi, South Carolina, and Georgia as likely to have been infected. Portions of North
Carolina and Virginia were infected in the late nineteenth century, but that was probably the result of a large influx of cattle from the Deep South during the Civil War. Before the
Civil War, North Carolina banned cattle from the Lower South from entering the state
between April 1 and November 1, which "largely kept cattle fever out of Virginia and
states to the north before the Civil War." G. Terry Sharrer, A Kind of Fate: Agricultural
Change in Virginia, 1-861-1920 (Ames: Iowa State University Press, 2000), 18.
15. Strom, "Making Cat Fish Bait," 1-15.
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2007 The Environmental Origins of Shifting Cultivation
16. For a good summary of this view, see, Sarah T. Phillips, "Antebellum Agricultural
Reform, Republican Ideology, and Sectional Tension," Agricultural History 74 (Fall 2000): 799-822.
17. Percentage of improved land in urban counties calculated from census data avail
able at the Geostat Center. Ulrich B. Phillips, History of Transportation in the Eastern
Cotton Belt to 1860 (1908; repr., New York: Octagon Books, 1968), 355.
18. Carr, Menard, and Walsh, Robert Cole's World, 39.
19. We tried to run various Hausman tests to correct for endogeniety, but all conceiv
able instrumental variables?farm size, per capita personal wealth, per capita total wealth, or some measure of per capita agricultural output?are themselves associated, perhaps
endogenously so, with high levels of improved land. This makes any result from such a test
highly suspect.
20. A related problem is a possible missing variable bias, as any positive association
between slavery and levels of improved land might be the result of variations in soil quality and commercial development not captured in our original specifications. Given the varia
tions of soils and topography within our broad topographical categories, the possibility of
a missing variable bias is quite strong.
21. In South Carolina, for example, the state government spent $40,367 on geological
surveys and agricultural research in the 1840s and 1850s, which amounted to a paltry 0.4
percent of total state expenditures in the period. Even Edmund Ruffin's well-known
geological survey of South Carolina received only modest state support. Ruffin, for ex
ample, had no staff to assist his efforts to survey the entire state. See, William M. Mathew,
Edmund Ruffin and the Crisis of Slavery in the Old South: The Failure of Agricultural
Reform (Athens: University of Georgia Press, 1988), 37-40. Expenditures on geological
surveys and the South Carolina State Agricultural Society were taken from the annual
session laws published annually in Columbia, usually titled Acts of the General Assembly
of the State of South Carolina. State budget data was taken from Lacy K. Ford, Origins of Southern Radicalism: The South Carolina Upcountry, 1800-1860 (New York: Oxford Uni
versity Press, 1988), 311.
22. David F. Weiman, "The Economic Emancipation of the Non-Slaveholding Class:
Upcountry Farmers in the Georgia Cotton Economy," Journal of Economic History 45
(Mar. 1985): 83-88; Ayers, Promise of the New South, 3-13, 55-62; Gavin Wright, Old
South, New South: Revolutions in the Southern Economy since the Civil War (New York:
Basic Books, 1986), 39-42; Michael M. Bell, "Did New England Go Downhill?" Geo
graphic Review 79 (Oct. 1989): 460-61.
23. Gilbert C. Fite, Cotton Fields No More: Southern Agriculture, 1865-1980 (Lexing ton: University Press of Kentucky, 1984), 85-86.
24. To determine infected counties, we consulted the Bureau of Animal Industry, Map
Showing Boundary Line of District Infected with Splenetic or Southern Cattle Fever, as
Defined in Order of Hon. J. M. Rusk, Secretary of Agriculture (Washington, DC: GPO,
1891). 25. For improvements along the Mississippi, see, Albert E. Cowdrey, This Land, This
South: An Environmental History, rev. ed. (Lexington: University of Kentucky Press,
1996), 122-23; Ayers, Promise of the New South, 194-95. Changes in the percentage of
improved land calculated from census data available at the Geostat Center.
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26. This fact fits well with Carville Earle's negative assessment of phosphates in "The
Price of Precocity: Technical Choice and Ecological Constraint in the Cotton South,
1840-1890," Agricultural History 66 (Summer 1992): 55-58. Census data on money spent
on fertilizers is available at Geostat Center.
27. Rural population densities calculated from "Urban and Rural Population: 1790 to
1970," US Census of Population: 1970 (Washington, DC: GPO, 1970), Vol. I, Pt. 1, Sec. 1,
Table 18; T. H. Breen, Tobacco Culture: The Mentality of the Great Tidewater Planters on
the Eve of Revolution (Princeton: Princeton University Press, 1985), 43; Lee Soltow and
Edward Stevens, The Rise of Literacy and the Common Schools in the United States: A
Socioeconomic Analysis to 1870 (Chicago: University of Chicago Press, 1981), 166-76.
28. Scholars have long documented the importance of prosperous rural markets in
stimulating early manufacturing. David R. Meyer, The Roots of American Industrialization
(Baltimore: Johns Hopkins University Press, 2003), 15-54, 162-88. See, also, John Ma
jewski, A House Dividing: Economic Development in Pennsylvania and Virginia before the
Civil War (New York: Cambridge University Press, 2000), 141-72; Diane Lindstrom,
Economic Development in the Philadelphia Region, 1810-1850 (New York: Columbia
University Press, 1978); John Majewski and Viken Tchakerian, "Markets and Manufac
turing: Industry and Agriculture in the Antebellum South and Midwest," in Global Per
spectives on Industrial Transformation in the American South, ed. Susanna Delfino and
Mich?le Gillespie (St. Louis: University of Missouri Press, 2005), 131-50.
29. Peter Coclanis, The Shadow of a Dream: Economic Life and Death in the South
Carolina Low Country, 1670-1920 (New York: Oxford University Press, 1989), 143-50;
David L. Carlton, "Antebellum Southern Urbanization," in The South, the Nation, and the
World: Perspectives on Southern Economic Development, ed. David L. Carlton and Peter
A. Coclanis (Charlottesville: University of Virginia Press, 2003), 39-AV, Mathew, Edmund
Ruffin and the Crisis of Slavery in the Old South, 162.
30. Soltow and Stevens, The Rise of Literacy and the Common Schools in the United
States, 166-76.
31. Ibid., 155-66; James M. McPherson, Ordeal by Fire: The Civil War and Reconstruc
tion, 3rd ed. (New York: McGraw-Hill, 2001), 27-29. On the lackluster state of the south
ern publishing industry, see, Alice Fahs, The Imagined Civil War: Popular Literature of the
North and South, 1861-1865 (Chapel Hill: University of North Carolina Press, 2001), 21-41
and Drew Gilpin Faust, The Creation of Confederate Nationalism: Ideology and Identity in
the Civil War South (Baton Rouge: Louisiana State University Press, 1988), 16-18.
32. Richard L. Bushman, The Refinement of America: Persons, Houses, Cities (New
York: Vintage Books, 1992), 390-98; Eric Foner, Free Soil, Free Labor, Free Men: The
Ideology of the Republican Party before the Civil War (New York: Oxford University
Press, 1970), 40-72; Foner, "Free Labor and Nineteenth-Century Political Ideology," in
The Market Revolution in America, ed. Stokes and Conway, 99-127; John Ashworth, "Free
Labor, Wage Labor, and the Slave Power: Republicanism and the Republican Party in the
1850s," The Market Revolution in America, ed. Stokes and Conway, 128-46.
33. Frederick Law Olmsted, A Journey in the Seaboard Slave States, with Remarks on
Their Economy (New York: Mason Brothers, 1859), 65, 66, 74-76.
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2007 The Environmental Origins of Shifting Cultivation
34. For these basic divisions, see, Sam Bowers Hilliard, Atlas of Antebellum Southern
Agriculture (Baton Rouge: Louisiana State University Press, 1984), 10-12. We also con
sulted the various state maps available at USDA, Natural Resources Conservation Ser
vice, "Southeast Coastal Plain and Caribbean: Soil Survey Region #15," http://
www.mol5.nrcs.usda.gov/states/index.html; Richard E. Lonsdale, Atlas of North Carolina
(Chapel Hill: University of North Carolina Press, 1967), 2-5; William Thorndale and
William Dollarhide, Map Guide to the US Federal Censuses, 1790-1920 (Baltimore: Ge
nealogical Publishing Co., Inc., 1987).
549