Rain follows the plow

Rain follows the plow is the conventional name for a now-discredited theory of climatology that was popular throughout the American West and Australia during the late 19th century.

... By this wonderful provision, which is only man's mastery over nature, the clouds are dispensing copious rains ... [the plow] is the instrument which separates civilization from savagery; and converts a desert into a farm or garden.

As later historical records of rainfall indicated, the theory was based on faulty evidence arising from brief climatological fluctuations that happened to coincide with settlement, an example of the logical fallacy that correlation means causation.

Emigrants on the Oregon Trail began reporting that the land in western Nebraska, previously known for its yellowed, dry vegetation during the summer, had seemingly become green.

Other prominent advocates of the theory were Ferdinand Vandeveer Hayden, the noted geographer who had explored and surveyed parts of the Rocky Mountains of Colorado; Samuel Aughey, a professor at the University of Nebraska; and Charles Dana Wilber, an amateur scientist and author.

Another hypothesis stated that the increased vibrations in the atmosphere due to human activity created additional clouds, from which rain fell.

Some historians have argued that the theory was embraced readily as an outgrowth of Manifest Destiny, the idea that the United States had a mission to expand, spreading its form of democracy and freedom.

In The Great Valleys and Prairies of Nebraska and the Northwest, published in 1881, Charles Dana Wilber wrote:In this miracle of progress, the plow was the unerring prophet, the procuring cause, not by any magic or enchantment, not by incantations or offerings, but instead by the sweat of his face toiling with his hands, man can persuade the heavens to yield their treasures of dew and rain upon the land he has chosen for his dwelling... .

[6] Observed trends of Midwest summertime cooling and increased rainfall over the last third of the 20th century have been linked to agricultural practices in the arid Great Plains, in an inversion of the Dust Bowl scenario.

In South Australia, George Goyder warned as early as 1865, in his famous report on farming in the state, that rain would not follow the plow.