Liquid manure

Amy Bogaard, an archaeobotanist at the University of Oxford, suspects that even as early as the Stone Age farmers had noticed the improved fertility of manured land. Her team investigated European digs for crops of cereals such as wheat and barley, as well as pulses such as peas and lentils.[1][4] Modern-day scholars think that the Babylonian Chronicles and Egyptian hieroglyphs report manuring practices, while Pliny the Elder and Seneca the Younger describe similar Roman and Teuton practices.[1][3]

Current American fertilizer practice dates back to the Post–World War II economic expansion era.[1] Powerful motorised tractors allowed farmers to haul large, heavy tanks on trailers around their fields, allowing liquids such as liquid manure to be easily and evenly applied near the plant root. Professional liquid manure spreaders may be costly and may require adherence to strict regulations, which has made renting the equipment attractive to some farmers.

Since at least 1982, health authorities have recognised that the O157:H7 bacteria, which has been responsible for significant numbers of human deaths, spreads through fecal transmission. The strain's low infectious dose, survival under adverse conditions, and potential for extreme disease severity prompt scientific attention. Radish, alfalfa sprouts, green onions as well as leafy green vegetables like lettuce, spinach are prone to be disease vectors, particularly when they are exposed to the pathogen just prior to harvest. In 1998, the United States Food and Drug Administration published the Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables. Particular attention is paid to concentrated animal feeding operations (CAFOs) because they are the source of most of the liquid manure that is spread on fields of vegetables in the United States. Rainwater runoff from these CAFOs was identified in the fatal Walkerton E. coli outbreak as the contaminant of municipal wellwater used for human consumption. Because of the relative infancy of industrial-scale vegetable fertilization by liquid manure, processes to minimize the infection risks were not final by 2007.[5]

• History of manuring practices
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  Spreading manure in 1906, photographed by Reuben R. Sallows.
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  Iowan pre-agribusiness manuring implements
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  A horse-drawn manure spreader
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  Post-agribusiness era liquid manure spreader
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  A liquid manure trailer in Austriain 2017
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  Liquid manure trailer
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  A liquid manure spreader in South Carolina
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  A liquid manure spreader at a trade fair in Belgium in 2009
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  Rear view of a liquid manure spreader at a trade fair in Belgium in 2009
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  Liquid manure tank in Belgium
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  A liquid manure storage silo in the Netherlands in 2012

• Chicken manure
• Cow manure
• Manure spreader
• Slurry pit
• Feces

Media related to Liquid manure at Wikimedia Commons