The Cullars Rotation is a soil fertility experiment on the Auburn University campus in

Auburn, Alabama Auburn is a city in Lee County, Alabama, United States. It is the largest city in eastern Alabama, with a 2020 population of 76,143. It is a principal city of the Auburn-Opelika Metropolitan Area. The Auburn-Opelika, AL MSA with a population ...

and is listed on the

National Register of Historic Places The National Register of Historic Places (NRHP) is the United States federal government's official list of districts, sites, buildings, structures and objects deemed worthy of preservation for their historical significance or "great artistic ...

. The Cullars Rotation experiment, which started in 1911, is the oldest ongoing

cotton Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus '' Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor pe ...

fertility experiment in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

, the oldest soil fertility experiment in the

Southern United States The Southern United States (sometimes Dixie, also referred to as the Southern States, the American South, the Southland, or simply the South) is a geographic and cultural region of the United States of America. It is between the Atlantic Ocean ...

, and the second oldest continuous cotton experiment in the world.

History

In the late 19th century, the land on which the Cullars Rotation sits was used in a number of agricultural experiments, including one that established the disease cotton rust was caused by a deficiency of

potassium Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosph ...

. In 1911, the Alabama Legislature set aside money for an experiment to study the long-term effects of

fertilization Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a new individual organism or offspring and initiate its development. Proce ...

on a three-year rotation of

, corn, and

wheat Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...

and soybeans. The Cullars site was chosen for this study and the experiment has continued unabated since. In 1938, the site was purchased by the Alabama Polytechnic Institute, which administered the study. In 2001, the portion of the Cullars site not occupied by the Cullars Rotation was landscaped as the grounds of the Jule Collins Smith Museum of Fine Art; however, a 40-foot buffer is maintained between the museum grounds and the rotation to ensure experimental integrity.

Experiment

The Cullars Rotation consists of three sets of 14 soil treatments, with one set of treatments for each of the three crops (cotton, corn, and wheat and soybeans) in the rotation. Each treatment fills a roughly 2000 square foot (184 m²) plot, with a two-foot (60 cm) buffer between plots. The 14 soil treatments are: # Legumes planted, but no

nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...

fertilizer A fertilizer (American English) or fertiliser (British English; see spelling differences) is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from ...

# No legumes or nitrogen fertilizer # Nothing added to soil # Nitrogen fertilizer added, but no winter legumes # No

phosphorus Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...

added # No micronutrients added # Excess

added # Rock phosphate added # No potassium added # Two-thirds of regular amount of potassium added # No

lime Lime commonly refers to: * Lime (fruit), a green citrus fruit * Lime (material), inorganic materials containing calcium, usually calcium oxide or calcium hydroxide * Lime (color), a color between yellow and green Lime may also refer to: Botany ...

added # No sulfur added # Complete fertilization with micronutrients # One-third of regular amount of potassium added Continuous farming of the plots which have not been given treatments have made certain sections of the Cullars Rotation some of the most nutrient poor soil in the United States.

Miscellaneous

The Cullars Rotation is located east of the grounds of the Jule Collins Smith Museum of Fine Art at the corner of College Street and Woodfield Drive in Auburn. As an ongoing experiment, the Rotation is not open to the public, but can be viewed from the museum grounds. The Rotation was placed on the National Register of Historic Places on May 18, 2003.

References

*Mitchell, C.C., Delaney, D.P., Balkcom, K.S. 2004. Alabama's "Cullars Rotation" Experiment (C. 1911) On National Register Of Historical Places bstract American Society Of Agronomy Meetings. {{National Register of Historic Places in Alabama Auburn, Alabama National Register of Historic Places in Lee County, Alabama Auburn University Farms on the National Register of Historic Places in Alabama Cotton industry in the United States

History

Experiment

Miscellaneous

See also

References