Irrigation Journal

11:49AM Oct 30, 2009
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Irrigation School
Want to learn more about irrigation techniques? Texas A&M University's Irrigation Technology Center offers online courses geared toward farmers. A course on center pivot irrigation is already available. Additional courses are being added.
"We have big plans. We hope to develop in stages for growers interested in both studying and getting credit for studying,” says Guy Fipps, Texas Extension irrigation specialist.
The irrigation courses are available for anyone and are eligible for continuing education credits. Completing them involves both reading and taking tests. They can be started at any time. Cost is $24.
For more information, go to the Irrigation Technology Center Web site at
Aerial Imagery System Helps Save Water
Traditionally, farmers irrigate by the calendar, but that can be wasteful—at times giving crops more water than they need. Doug Hunsaker, an ag engineer at the USDA–Agricultural Research Service's Arid-Land Agricultural Research Center in Maricopa, Ariz., is using remote-sensing technologies to conserve water by estimating crop needs at specific sections within fields, rather than assuming those needs are the same across the field.
Ideally, farmers could identify areas with high or low water needs with data transmitted to their computers and, using either a drip or a sprinkler system, adjust irrigation levels based on the data.
In a recent study, Hunsaker collected remote sensing images from aerial surveys of a 4-acre cotton field divided into 40 plots. The imagery tracked plant growth and water needs by capturing reflected light from the field in red and near infrared wavelengths; the bigger the cotton plants, the more infrared light captured in the images.
Hunsaker used a computer program to analyze the imagery, determine optimal placement of ground-based sensors and predict the variability of water needs throughout the field.
By conducting periodic aerial surveys during two growing seasons, he found that the system could accurately predict the diversity of crop water needs throughout the field. He is currently evaluating ground-based sensors that would reduce costs by eliminating the need for all but one aerial survey each season.
Energy Cost Calculator
How much money could you save if your pumping plant was more efficient?
A University of Nebraska online spreadsheet can help you calculate how much you can save by improving the efficiency of your system. Tom Dorn, Lancaster County, Neb., Extension educator, developed the simple tool, which requires entering data from irrigation records.
Step-by-step instructions will help you navigate the spreadsheet to determine your pumping plant's efficiency and the amount of money you could save if the pumping plant were operating up to Nebraska performance standards.
"With the information, irrigators can calculate how much they can afford to spend, based on the interest rate available,” Dorn says.
When considering inefficiencies in the system, Dorn suggests, irrigators should look at the entire system, including the pump, gearhead, PTO shaft and power unit. Inadequacies in any part of that system can increase energy use. While it's costly to pull a pump, sometimes the cost of unneeded energy is high, too.
To access the spreadsheet, go to
Flow Meters
Flow meters get no respect. At least that's what Tom Scherer, North Dakota Extension ag engineer,
says his research indicates. Often, flow meters don't work because of old age or winter damage.
To take part in the sprinkler conversion program from the Natural Resources Conservation Service's Environmental Quality Incentives Program, center pivot flow rate must be checked. That means flow meters must work properly.
Flow meters can help work out a lot of management information for chemigation, selecting and modifying sprinkler nozzles, calculating pivot application rate, checking well production and tracking pump performance, Scherer says.
To protect flow meters, remove them from systems in the fall and store them in a warm place during the winter, Scherer says. Cover the hole in the pipe with a piece of tin.
Drought Dodgers
There is no need to stress out. More research aimed at corn drought is on the way.
Pioneer Hi-Bred is expanding its corn drought research efforts at facilities in Plainview, Texas, and Manhattan, Kan.
These locations have traditionally focused on sorghum and now will have additional research on corn. The expanded facilities will allow Pioneer to establish managed stress environments, including needed irrigation systems. Native and transgenic traits will be evaluated and characterized at the research facilities.
Joe Keaschall, Pioneer corn research director, wishes there was a magical gene for the development of drought-tolerant hybrids. "But truth is, drought is a complex issue with yearly variations in the timing and intensity of water deficit and high-temperature stress,” he observes.
New yield test locations specifically targeted at drought product development have been established at the Manhattan facility. A breeding nursery has been established at the Plainview site, and several thousand inbreds are being evaluated. Also, limited irrigation sites have been established in Texas for targeted drought yield evaluation.
Both facilities will be dedicated to Drought I and Drought II product development initiatives. Drought I efforts combine native drought genes with needed traits in elite adapted inbreds for drought-prone areas. Drought II is focused on transgenic gene evaluation and integration into the most elite and adapted germplasm. Herbicide, insect and disease resistance will continue to be key traits for industry-leading drought hybrids.
Pioneer also conducts drought research in Garden City, Kan.; LaSalle, Colo.; York, Neb.; Woodland, Calif.; and Viluco, Chile.