Like gasoline in a car, water fuels the growth of Richard Dobbins' corn and soybean crops each July and August.
"We often get a 50- to 60-bushel yield response from just 5 inches of water applied during that timeframe,” says Dobbins, who owns North Concord Farms near Albion, Mich.
Dobbins' 2,800 acres of crops are planted on light soils and hilly terrain, and roughly 1,000 acres are irrigated.
This year, Dobbins worked with Associate Field Agronomist, Missy Bauer, to evaluate the uniformity of his irrigation applications.
Bauer placed calibration cups about every 10 feet along the center pivot and then measured the volume of water collected in each.
"When you measure the volume of water in the cups, it should be consistent from one end of the center pivot to the other,” Bauer explains. "When you find a cup with an inconsistent amount of water, you need to make a correction.”
Lyndon Kelley, Irrigation Educator for Michigan State University and Purdue University, offers these timely management tips to maximize the efficacy of your irrigation practices.
Make sure your irrigation application is uniform. There are easy catch can systems available to evaluate the uniformity of the application of your system.
Know your actual application. The catch can system available to evaluate the uniformity of the application of your system will also tell you the actual application rate.Your system provider or the website below can provide you with tools to print a corrected percent timer chart if needed.
Assure yourself of an adequate water supply. Five gal/minute/acre pump capacity (.25 in./day) will meet all crop needs except for hot long dry spells of 15 days or more. That means a 500 gal/minute pump can provide 1” every 4 days on 100 acres.
Schedule irrigation applications. Have a plan to determine the appropriate amount of water to be applied to a crop at the correct time to avoid yield loss and conserve water. Under watering will reduce yield potential and leave valuable crop inputs under utilized. Over watering is equally bad as it can waste natural resources and potentially push nutrients out of the root zone.
Kelley says for more information on effective irrigation management practices, go to the St. Joseph County MSU Extension Irrigation website
. Follow the irrigation link on the left column of the page. Once on the irrigation website, you will be able to locate all of the items briefly addressed here as well as additional resources.