(Rual Indiana) - Farmers should have a strategy for irrigating their crops to achieve better yields and conserve water. That’s according to Lyndon Kelley, Irrigation and Water Management Educator for Michigan State University and Purdue University Extension.
Kelley said farmers should not simply wait until their corn and soybeans exhibit physical signs of being thirsty before irrigating because it can take several days to cover an entire field with one inch of water. “That’s a little too late to start irrigating,” he said. Instead, a schedule should be developed to know when to start irrigating before symptoms of stress in a crop begin showing.
Kelley said one of the most important things farmers should know in developing a schedule is how much water their irrigation system produces. For example, he said a 500 gallon per minute irrigation pump is able to cover a 100 acre field with one inch of water in four days. Kelley said a system with less capacity working the same field requires irrigating to begin sooner to reach the entire field with one inch of water before signs of distress begin emerging in the crop.
Knowing the length of time it takes to water an entire field before the start of a dry spell also helps keep the plant fresh before receiving water manually or naturally again. Kelley said knowing the capacity of the irrigation system is also important in times such as before and after tasseling when corn requires more water and the timing of the water can help properly fill out the ears.
He said a schedule for irrigating based on capacity also helps farmers raising corn and soybeans by avoiding a late start on soybeans when soybeans need more water after corn is finished tasseling. “If we split the acreage up between those two crops we can start feeding corn and still have the capacity to feed the soybeans afterwards,” Kelley said.
Kelley said using tools to measure soil moisture is also important to know when to start irrigating so the roots of plants don’t become too dry before manually applied water soaks deep enough into the ground. How much moisture is in the soil also helps prevent applying too much water which leads to waste of a natural resource and run off. Knowing how much water to apply based on soil moisture also helps with more efficient use of fertilizer, he said.
Kelley also noted farmers are applying about one inch of more water to their crops despite annual rainfall being about four inches higher over the past 10-years.