Benefits of Limited Irrigation
Friday, January 3, 2003
filed under: Irrigation/Water Use
Many growers in the High Plains who irrigate their crops realize that their well capacities are declining, and that changes are needed in their cropping system.
“They might have had wells pumping 700 gallons per minute 10 years ago that’s pumping at 550 gallons per minute now, and they know in the future it’s going to keep dropping. That’s what’s getting them to look more at limited watering strategies,” says Joel Schneekloth, Colorado State University regional water Resource Specialist.
Schneekloth, based in Akron, Colo., says the dry conditions the last few years has spurred an interest in “limited irrigation,” which might be described as simply using irrigation water more efficiently. “Many are finding that they just can’t keep up with a full pivot of corn anymore, especially in dry years like 2002,” he says.
A growing portfolio of research—and increasing on-farm experiences—indicates that sunflower can be a profitable limited-irrigation cropping choice for producers in the High Plains, which can also help conserve valuable irrigation water use. That’s why the National Sunflower Association coordinated a series of seminars recently in the High Plains, on how sunflower can fit within a limited irrigation system. Cooperators included the Extension Service at Colorado State University, Kansas State University, the University of Nebraska, and Texas A&M. The seminars were partially funded by a grant from the USDA’s Risk Management Agency.
At the well-attended seminars, Max Dietrich, the NSA’s production coordinator, outlined the advantages of sunflower in a crop rotation, including the fact that the crop:
“Sunflower uses as much or more soil water as other crops. It will typically use about 22 inches of water during a growing season. But it uses about 15-20% less water than corn, and does well in dry conditions due to it’s deep, aggressive root system,” Dietrich says.
- Handles heat and water stress better than many crops.
- Helps spread planting and harvesting times.
- Utilizes subsoil nutrients and moisture better than any other crop.
- Can increase overall farm profits.
- Can help producers spread irrigation intervals.
Water is most critical to sunflower at stand establishment and growth stages R-4 to R-8. “Sunflower is very responsive to irrigation or rainfall just prior to flowering through seed filling,” says Dietrich.
Too much water during sunflower’s vegetative stage can actually be detrimental, he says, resulting in taller plants that may lodge easier, and an increased susceptibility to disease. “Sunflower is a crop that prefers ‘dry feet,’” says Dietrich, referring to the crop’s root system. Rainfall will usually be adequate for vegetative growth, he says, and irrigation is necessary during sunflower’s vegetative growth stages only to ensure plant survival in drought conditions.
Though there are no silver bullet solutions to drought (with the exception being the return of normal moisture) Schneekloth says there are strategies to help producers maximize returns and stretch water as much as possible during drought conditions. “Allocate your water resources by determining what crops are to be irrigated and which will be dryland, how many acres of each crop will be irrigated or dryland, and how much water to apply to a crop,” he says.
Schneekloth says producers should consider adjusting their crop rotations under irrigation by growing crops that have varying peak water needs. One example might be winter wheat, corn, and sunflower on three pivots or one pivot split into thirds, irrigating for stand establishment and during the reproductive stages of all three crops. Irrigation will no longer be needed on the winter wheat after July 1, when irrigation efforts can be focused on corn, which should be tasseling around July 20. The corn crop’s critical peak water period will conclude around August 1, and irrigation efforts can then be focused on sunflower, which will begin blooming around August 10.
Free CDs on Limited Irrigation
The NSA has free computer CDs available that outline topics discussed in the recent limited irrigation seminars. Along with tips on limited irrigation, it includes timely, beneficial information on various aspects of successfully producing sunflower, from planting to harvest to pest control. Request the CD by contacting Max Dietrich at the NSA, 1-888-718-7033 or email@example.com
K-State, NDSU Crop Budgets Online
Kansas State University has cost-return budgets for center-pivot irrigated sunflower, double-crop sunflower, and for various regions of the state, on the K-State web site, http://www.oznet.ksu.edu. Click on the “new publications” link, then under the Economics heading, click on “Farm Management Guides, Revised 2002,” which links to an eight-page PDF index of crop budgets, including sunflower.
North Dakota State University’s Farm Management Planning Guides, with crop budgets for 2003, can be found online at http://www.ext.nodak.edu/extpubs/ecguides.htm. The budgets indicate that in most areas of N.D., sunflower is among the crops with the best profit potential, even despite conservative budget yield and price estimates (1,330 yield and 10.7 cent price in southwest N.D., for example) and not factoring oil and NuSun premiums.
Growers without Internet access can call the NSA at 1-888-718-7033 for assistance in obtaining printed copies of the crop budgets.