- PRODUCTION -
Furrow Irrigation Helps
By Amanda Huber
What Kelly, who farms cotton, milo and hard red winter wheat in Altus, Okla., can plan on is that none of that will come from the sky. It all comes from the lake northeast of Mangum and flows by gravity to his farm through a series of canals, ditches and gates. For Kelly, irrigation efficiency is a necessary part of his operation.
“Normally, the rains stop the second week in June until around early to mid-August,” he says. Kelly, who produces cotton on 800 to 1,200 acres of mostly irrigated land, depends on his rotation cycle and economic forces.
“The lake for our irrigation district holds about 135,000 acre-feet of water,” he adds. “About the last week of June or the first week of July, we will see how much water is there.”
Based on assessed acres, each producer gets a water allocation.
“We start irrigating around the first week in July and stop around the first week in September,” he says. “But, we can’t get the water immediately. It’s 35 miles to the lake, and it takes 24 hours for it to run from the lake to here.”
Every Other Row
Kelly plants cotton on 30-inch rows and irrigates every other row.
Mike Kizer, irrigation Extension specialist for Oklahoma State University, says this practice is one efficiency.
“The most inefficiency you have in the system is running water down the newly formed furrow the first time,” he says. “The first time a furrow is irrigated, efficiency is lost in smoothing out the furrow. There is more friction and resistance.”
Kizer says some producers will irrigate one furrow the first time, then switch to the other furrow the next. However, he says the water will advance more rapidly if the producer sticks with the same furrow each time.
That watering every furrow may offer better root distribution is a tradeoff that must be considered. With little irrigation water to work with, it may be best to be as conservative as possible and let the roots grow to the water.
Collect That Runoff
Another efficiency is in creating a tailwater collection system so that excess irrigation water can be recycled and reused in that field or another.
“The irrigation water runs off the fields and into a pond, and I catch it and use it again,” Kelly says.
Putting out just enough water so that it doesn’t run out the end is not possible in this type of furrow irrigation, says Shane Osborne, OSU associate Extension specialist who is located at the research center in Altus.
“Implementing the tailwater system is reusing water that is normally wasted,” he says.
Osborne says that many producers in the area are moving to drip irrigation, which is an even more efficient form of irrigation.
Attention To Details
Kelly has not made that move yet, and so he continues to improve his furrow irrigation capabilities. To conserve water, he uses minimum-tillage.
“I’ve been experimenting with varying degrees of minimum-tillage to strike that balance between less tillage and water-use efficiency,” he says.
Kelly also works to keep his ditches maintained so that no breaks occur where precious water can be lost.
“These concrete ditches have been here since the mid-70s,” he says. “Every now and then, we hit one with a tractor, so we do have to patch and take care of them. I also use polypipe, which is very flexible, to take the place of dirt ditches that are less efficient.”
Yields almost consistently ranging near three bales per acre are evidence that Kelly works at keeping his furrow irrigation system efficient to gain maximum production each year.
Contact Amanda Huber at (352) 486-7006 or firstname.lastname@example.org.