Instructional Guide on Irrigation Practices for North American Crops
In the last 100 years, large-scale irrigation infrastructure has become a necessity in agriculture, with center-pivot irrigation systems playing a significant role. These above-ground irrigation machines, known for their size and the circular crop patterns they create, are a common method for watering crops efficiently.
Center-pivot irrigation systems consist of a tower, a rotating boom, individual sections of pipe called spans, and sprinkler heads. The pipe for each span is usually made from galvanized steel, but aluminum is also sometimes used. The water supply, usually located at the center of the field, must be able to supply a sufficient amount of water, with each boom flowing approximately 1,000 gallons per minute.
Hydrostatic pivots, a common type of center-pivot irrigation system, pose an environmental hazard due to potential hydraulic leaks. To mitigate this risk, hydrostatic pivots generally use a non-toxic hydraulic fluid specifically engineered for pivots. Some manufacturers use hydrostatic drives in center-pivot irrigation systems to combat theft, as these tend to be mechanically simpler and safer to work on compared to electrically driven ones.
Wheel line irrigation, a lower-cost method used for rectangular fields that center-pivot machines can't fully utilize, is another method of irrigation. It uses lengths of pipe connected to large spoked wheels and a drive unit at the center of the line. While it requires less water compared to center-pivot systems, it does not continually move across the field; instead, it needs to be manually moved several times a day.
Hose reel irrigation, which lies between the labor-intensive wheel line and the hands-off center-pivot irrigation, is a more modern method. It uses a large reel of flexible polyethylene pipe, towed into the field and connected to a tower-mounted gun. The hose reel is wound back onto the reel as water is used, pulling the gun back to the center of the field. This method is less labor-intensive than wheel lines and can be easily scaled up or down.
The gun tower is typically a high-flow impulse sprinkler that covers a circle or semi-circle a hundred feet or more in diameter. Artificial irrigation, such as diverting water from rivers, lakes, and wells, has been used in agriculture for a long time. However, as the demand for food grows, so does the need for efficient and sustainable irrigation methods.
Key companies responsible for manufacturing and distributing above-ground irrigation systems like center pivot irrigation in North America include Lindsay Corporation, Valmont Industries (Valley Irrigation), and T-L Irrigation. These companies are at the forefront of innovation, developing new methods and technologies to address the challenges faced by modern agriculture.
Agriculture was invented to address the fundamental issue of human survival - the need to find the next meal after finishing a meal. Today, advancements in irrigation technology continue to play a crucial role in ensuring that we have access to a steady supply of nutritious food. Whether it's through center-pivot irrigation, wheel line irrigation, or hose reel irrigation, the evolution of irrigation methods is a testament to human ingenuity and our relentless pursuit of a sustainable food supply.
