thumb|upright=1.25|Dryland farming in the [[Province of Granada| Granada region of Spain]]

Dryland farming and dry farming encompass specific agricultural techniques for the non-irrigated cultivation of crops. Dryland farming is associated with drylands, areas characterized by a cool wet season (which charges the soil with virtually all the moisture that the crops will receive prior to harvest) followed by a warm dry season. They are also associated with arid conditions, areas prone to drought and those having scarce water resources.

Process

thumb|Dryland farming caused a large [[dust storm in parts of Eastern Washington on October 4, 2009. Courtesy: NASA/GSFC, MODIS Rapid Response.

In marginal regions, a farmer should be financially able to survive occasional crop failures, perhaps for several years in succession. Survival as a dryland farmer requires careful husbandry of the moisture available for the crop and aggressive management of expenses to minimize losses in poor years. Dryland farming involves the constant assessing of the amount of moisture present or lacking for any given crop cycle and planning accordingly. Dryland farmers know that to be financially successful they have to be aggressive during the good years in order to offset the dry years.

Dryland farming is dependent on natural rainfall, which can leave the ground vulnerable to dust storms, particularly if poor farming techniques are used or if the storms strike at a particularly vulnerable time. The fact that a fallow period must be included in the crop rotation means that fields cannot always be protected by a cover crop, which might otherwise offer protection against erosion.

Some of the theories of dryland farming developed in the late 19th and early 20th centuries claimed to be scientific but were in reality pseudoscientific and did not stand up to empirical testing. For example, it was alleged that tillage would seal in moisture, but such "dust mulching" ideas are based on what people imagine should happen, or have been told, rather than what testing actually confirms. In actuality, it has been shown that tillage increases water losses to evaporation. The book Bad Land: An American Romance explores the effects that this had on people who were encouraged to homestead in an area with little rainfall; most smallholdings failed after working miserably to cling on.

Dry farming depends on making the best use of the "bank" of soil moisture that was created by winter rainfall. Some dry farming practices include:

Further reading

  • Henry Gilbert, Dryland Farming: January 1982–December 1990 (Beltsville, Md.: U.S. Department of Agriculture, National Agricultural Library, 1991)
  • Mary W. M. Hargraves, Dry Farming in the Northern Great Plains: Years of Readjustment, 1920–1990 (Lawrence: University of Kansas, 1993)
  • Oklahoma State Board of Agriculture, Report (Guthrie, OK: n.p. 1908)
  • Dr. John A. Widtsoe, Ph.D. Dry-Farming, A System Of Agriculture For Countries Under A Low Rainfall (NY: The Macmillan Company, 1911)
  • Victor Squires and Philip Tow, Dryland Farming: A Systems Approach – An Analysis of Dryland Agriculture in Australia (Sydney: Sydney University Press, 1991)
  • O'Bar, Scott, (2013). Alternative Crops for Drylands – Proactively Adapting to Climate Change and Water Shortages. Amaigabe Press, Santa Barbara, CA
  • Encyclopedia of Oklahoma History and Culture – Dry Farming
  • P. Koohafkan and B.A. Stewart, Water and Cereals in Drylands published by The Food and Agriculture Organization of the United Nations and Earthscan (PDF)
  • Steve Solomon, Water-Wise Vegetables: For the Maritime Northwest Gardener (Sasquatch Books, 1993)