The Agricultural Impacts of the Dirty Thirties (Fall 2012)

As the Dust Bowl of the 1930’s hit the southern Great Plains, America was subject to its own man-made atonement, a reckoning for the careless neglect of the environment. Flocks of birds fled before the columns of dust rising thousands of feet in the air, so black that noon felt like midnight. The sun was blocked for days at a time, while winds of 60 miles per hour and higher raged unchecked across the open lands of the Great Plains. The Dirty Thirties of drought and wind-driven soil erosion lasted from 1931 to 1939, altering the environment and economy of the nation. The causes of this extraordinary event have been closely analyzed and conservation solutions continue to impact current agricultural practices in the hopes that the land will never be subject to a catastrophe of this magnitude again. The historical forces of environment and earth, economics, and science and technology influenced the Dust Bowl as factors of both the problem and the solution.

The effects of the Dust Bowl were strongest in the southern Great Plains region consisting of southeast Colorado, northeast New Mexico, west Kansas, and the panhandles of Texas and Oklahoma. These ranges added up to 97 million acres of highly erodible and drought-prone land, stretching 400 miles north to south and 300 miles east to west. The worst of the storms shifted annually to affect various areas at different times, with changes in precipitation levels determining the drought’s location. Wind erosion was most severe in a hundred mile circle centered on Liberal, Kansas. The storms of the Dust Bowl could affect up to 50 million acres at one time. When damage was all totaled, the wind had removed an average of 5 inches of topsoil from over 10 million acres. This man-made disaster still stands as one of the most extreme disturbances of the environment of the United States.

The factors causing the Dust Bowl are important to consider when examining the agricultural impact of the Dirty Thirties. Soil composition, climate severity and a history of drought made the region fragile to begin with. The soil of the southern Great Plains contained significant levels of potassium, nitrogen, and phosphorous nutrients. Its soil types ranged from sand to deep loam, leaving many areas vulnerable to the changes of the semiarid climate. Annual precipitation levels averaged less than 20 inches, and droughts of 10 years or more were known to occur about every 55.6 years. Low humidity and high evaporation rates were characteristic of the climate in the region. There were sharp seasonal contrasts between temperature and precipitation levels of winter and summer. Freezing and thawing cycles loosened the topsoil, exposing it to the strong winds that occurred regularly in the spring season and continued into the summer. Dust storms and drought were natural phenomena that had transpired in the past, but never to the severity seen in the Dirty Thirties. These fierce Dust Bowl storms were caused by the irresponsible agricultural practices of the farmers who settled the plains and began the work of harvest over expanses of land.

Agricultural mistakes in this region were made when farmers imposed cultivation techniques suited for humid climates with wet soil on the semiarid dry soils of the southern Great Plains. Farmers did not realize or understand the necessity of grassland management. At first, soil disturbance was limited due to the fact that early practices relied on the ability of draft animals. Tough prairie sod had to be broken to plant crop fields, but the process of cultivation was slow. New technologies contributed greatly to the quick explosion of land conversion, as sharp steel plows capable of breaking the root systems and the tough prairie sod were designed. The progression of improved machinery allowed greater and greater stretches of land to be farmed, which began to expose underlying soil to wind erosion. During the time of the “Great Plow-Up” of 1910-1920, 5.2 million acres of grassland were converted to wheat fields. This unprecedented frenzy of land conversion continued up to the Dust Bowl, with 1 million acres in southwest Kansas alone plowed for cropland between 1920 and 1930. The wheat market was high during World War I, when demand for wheat increased because of European Allied need. Successful yields in times of high precipitation gave farmers the funds to invest in better plowing and harvesting implements, letting them handle more cropland in less time. This ultimately encouraged them to buy more machinery on credit and convert more land to fields to pay for it. “Suitcase” farmers became a problem as land owners could hire custom farmers from afar to work the land at planting and harvest time. These farmers did not remain in the region during the rest of the year, and therefore had no real incentive to commit to long-term conservation of the soil. The economic factor of the Great Depression marked the beginning of the wheat market crash. When profit was no longer being made, most of the suitcase farmers abandoned the lands they had tilled up. Desperate farmers still living in the region gambled on the prospects of planting more land in the hopes of a better harvest to come. Drought conditions set in and farmers hoping to recover their losses converted yet more land to harvest wheat. Moreover, practices that had been successful in times of beneficial rains were becoming increasingly problematic with the shift of climatic conditions to drought. Most farmers neglected to plow under crop residues to maintain the soil’s organic matter. Organic matter allowed soil to absorb moisture; without it, the soil quickly became incapable of using precipitation efficiently. The Great Plains soil dried out and was unable to recover in times of rainfall. Livestock overgrazing was common on harvested fields and remaining grassland, removing vegetative protection on the ground. Over-tilled and overgrazed land became displaced as drought pulled the final trigger of the Dust Bowl.

At first farmers were not overly concerned with the dust storms that came; small blows had occurred in the past and farmers of the early 30’s were more disturbed by crop failure, low markets, and the economic depression. Concern over the wind erosion finally arose in the public in 1933, when a mid-November storm relocated Great Plains soil as far east as Lake Superior. The Dirty Thirties quickly escalated to unbelievable extremes. By mid-March, 1934, the wind was uprooting even the wheat fields whose root systems were developed. As drought conditions worsened, about 300 million tons of soil were displaced to the east, reaching Washington D.C., New York City, and ships anchored miles out in the Atlantic Ocean. In May 1934, a 36-hour dust storm spanned 1500 miles from the northern United States border to Oklahoma and from the Rocky Mountains to the Great Lakes. Throughout the years of the Dust Bowl, February, March and April became the “blow months”, generally harboring the worst of the storms. For the farmers of the region it meant destruction of their lives. Pastures, barnyards, and homesteads were drifted in and covered by the dirt. An estimated 2.5 million people were forced to leave the Great Plains during the Dirty Thirties. Some of the blame for the agricultural practices was traced back and placed on the Homestead Act of 1862. Farmers argued that the farm allotments it had outlined were so small that often they had no choice but to convert all the land given to them into fields just to get enough return to provide an income. Small farms had limited solutions for controlling wind erosion, and as soil blew downwind the damage compounded on neighboring farms. Cross-farm effects occurred as the heavy soil particles in the wind would fan out and destroy vegetation and stable soil crust in other areas. Consequently, more soil was exposed to erosion as the winds continued the progression of damage. As the Dirty Thirties’ years passed there was little improvement of the storms. To alleviate the many problems contributing to the prolonged Dust Bowl, the federal government began to take an active role in repairing the region’s suffering.

During the Dirty Thirties, President Roosevelt’s New Deal economic strategy helped to keep many of the hungry farm families afloat at a time of destruction of their homes and income. The government also purchased almost 4 million acres of land during the Dust Bowl to begin the restoration process of converting them back to national grasslands. The United States Department of Agriculture formed a drought area committee headed by Morris Cooke to report to President Roosevelt the nature, causes, and suggested methods to alleviate the continuing Dust Bowl. They recommended amending the Homestead Act and emphasized the need for practices that would provide run-off reduction and improved water storage in the soil. The committee called for the funding and application of new practices that were research-tested and environmentally suitable. Several new legislative acts established land policy revisions as reward systems for farmers who used newly developed alternative tillage practices. The federal Soil Erosion Service was created in 1933, an agency that encouraged farmers to take high-risk erodible land out of crop production by giving them financial compensation to turn those acres into permanent pasture or forest. By 1937, soil conservation districts were established throughout the Great Plains region to allow individual farmers to enter into these soil conservation contracts.

Improvements in practices started with undercutting the soil, as opposed to inverting it, to preserve more surface crop residue. The Graham-Hoeme plow was a technology that helped fight the Dust Bowl, as it controlled weeds without displacing the organic matter of the topsoil. Increasing crop residue also amplified the ability of the soil to store and conserve water. Methods of contour plowing were endorsed by the government committee, as plowing perpendicular to the slope of the land better restricted downhill runoff. Strip cropping with windbreaks of trees or bushes slowed the wind speeds at the ground surface to reduce erosion. Strip cropping with fallow, or undisturbed sections of land, allowed for areas of higher soil moisture and roughness that reduced erosion as well. These strip cropping barriers could protect fields downwind for distances ten times their height. Investment in this practice allowed a farmer to retain topsoil while protecting downwind crops from damage by dust particles. Crop rotation was introduced with a wheat-sorghum sequence to maximize use of the region’s summer rains and contribute to the diversity of organic matter of the soil composition. Eventually these improved practices, combined with the fade of drought into higher precipitation, were enough to pull the southern Great Plains out of the Dust Bowl. By the time World War II provided farmers with a renewed wheat demand, the region’s market and environmental balance was recovered.

Many of the agricultural practices and governmental agencies whose roots were established in the Dust Bowl remain active and effective in modern agriculture. Improvements in the soil quality of the Great Plains have continued with no-till and reduced till practices increasing water storage from the 20% of the Dust Bowl to 40% water storage effective today. Crop rotation and field fertilization have further stabilized the region’s economy. Cattle management reduces overgrazing. Ultimately, irrigation expansion was the most essential solution to the drought trigger of the Dust Bowl. The Ogallala aquifer is an underground reservoir spanning from northern Texas up to North Dakota. Currently its water is pumped up to irrigate cropland. There is concern that if this resource of water were ever to decline, the Dust Bowl events could begin again. Today the federal U.S. Farm Bill provides the most funding for conservation initiatives. Its Grassland Reserve Program and Conservation Stewardship Program are rooted back in the problems of the Dust Bowl. The reauthorization of this bill’s funding will be voted on by Congress this year.

The Dirty Thirties were influenced by several history forces. Earth and environment were the central forces at work during this period. They were affected by human activity and in turn impacted the lives of the people of the Great Plains. The Dust Bowl’s extreme storms and vast destruction of land was a man-made disaster that forever changed the earth and environment of this region. The forces of science and technology contributed to the buildup of the conditions that started the Dust Bowl, as agricultural machinery provided innovative and faster ways of converting land, at a time when responsible practices were not enforced. The force of economics augmented the problem and fueled the irresponsible use of technology. Economic markets were driven by World War I and II and inevitably crashed during the interval between them with the Great Depression. Frantic farmers invested too much in the gamble of growing wheat, converting huge stretches of land with technology and practices that were not suited for the semiarid climate and time of drought. Eventually, the forces of science and technology were used to find the way out of the disaster and repair the damage of their past misuse. Current agricultural practices and legislature remain as direct results of these historical forces. Ultimately, through the horrors of the Dirty Thirties, the history force of earth and environment gave mankind an everlasting lesson of the consequences of irresponsible agricultural practices.


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