James Hampton faced a dilemma when he acquired a 70-acre cotton field prior to this planting season. The Dexter, Mo.-farmer didn't want to go into the season without a way to irrigate it. Unfortunately, the field didn't fit traditional irrigation methods.
“When James rented this farm, he thought he could grade it and furrow irrigate,” said Allen, James' father, who advised him on the project. “But it was too sandy. And a center pivot on 70 acres is pretty expensive.”
They turned their attention to sub-surface drip irrigation, but not without some reservation, according to Allen. “I've been seeing the drip irrigation in magazines for years. But I really didn't think it was the way to go.”
The Hamptons changed their minds after the drip manufacturer Netafim Irrigation Inc., based in Fresno, Calif., flew them to Lubbock, Texas, to view several drip systems in operation.
“The Lubbock farmers are in a limited-water supply situation and for them, the system is more advantageous because they can use a small amount of water under the ground,” Allen said. “It doesn't run off. It doesn't evaporate.”
The Hamptons realized that drip was simply a very efficient way to irrigate. James decided to lay down Netafim's sub-surface drip irrigation system, which can cost between $700 and $1,000 per acre to install.
James' lender, Gordon Waller, First State Bank and Trust Co., in Sikeston, Mo., recognized that the investment in drip might a good way to reduce risk.
“It's an experiment for all of us,” he said. “Cotton farming is very important in our part of the world. From a risk management standpoint, with low commodity prices and high input costs, we're looking at all kinds of ways to limit the risks of putting in a crop.”
Early on, there were some anxious moments for the Hamptons, who together farm 2,500 acres, including 1,600 acres of cotton, 200 acres of rice and 700 acres of beans.
For example, they went with a no-till program to not disturb the underground tape. “But it was so terribly dry this spring, we had some problems with emergence,” Allen said.
But as cotton came up and grew off, the Hamptons noticed excellent fruit retention on the field, planted in Stoneville 4892BR and Paymaster 1218 BG/RR.
And where they ran a hooded sprayer through the field late in the season, it's clean, but pigweeds are infesting the rest of the field, something the Hamptons chalk up to lack of experience in no-till and not knowing the weed history of the field. The hooded sprayer was not run over the rest of the field because it was knocking off some bolls.
“That was my decision,” the younger Hampton admitted.
As of mid-September, the 70-acre, half-bale, sand blow had been turned into a decent no-till field with about 2 bales worth of bolls hanging on it, including a nice top crop.
Another key for the Hamptons was making sure the soil was in shape for irrigation. “If the soil tests say put out two tons of lime, we put out two tons of lime. If it needed 15 pounds of copper sulfate, we put out the copper sulfate. We didn't cut any corners on that field.”
Netafim is a consortium of several companies, each of which contribute components to the turnkey drip irrigation system. Here's how it's set up on the Hampton farm:
Well water from a 400 gpm submersible pump flows through a chemigation check value — which protects the water source. It's then treated with chlorine and NpHuric acid stored in two large tanks. “The acid helps correct the pH and provides a nitrogen source while the chlorine helps oxidize the iron so we can filter it out,” James said. “One of the biggest problems up here is a high iron content.”
The water then runs through two large filters, then to an injector where P, K, micronutrients, or other chemicals can be added.
On the Hampton farm, the system is computerized and housed in a small tin building next to the field. “We can call the computer up from anywhere,” Allen said, “and tell it to water 10 to 15 acres of the field or all of it.”
The sub-surface tapes are about 14 inches deep, set on 76-inch centers, or under every other row in Hampton's 38-inch row cotton. The Hamptons stress that the tubes provide good lateral flow of water and nutrients and can coax water close to the surface if necessary.
The projected life of the system is about 20 years, according to the manufacturer.
The drip system will put out about 0.25 inch of water per acre, per day, but Jim Phene, district sales manager for Netafim, stresses, “We're not watering the whole field, just the root zone. This summer, the wind was blowing 25 miles an hour, it was close to 100 degrees. I know our evaporation rate was in excess of a 0.5 inch, but with drip, the cotton didn't appear to stress.”
Phene says the biggest advantage of drip irrigation is the ability to inject fertilizers and other chemicals. “On irrigated fields in west Texas where yields are slightly more than a bale, growers using the drip system are yielding between 2.5 and 4 bales an acre.”
The system does cost $300 per acre more than a center pivot, but in fields where a “windshield wiper” pivot is called for drip is less expensive, Phene said. “On a quarter section, the drip system will irrigate 27.5 percent more acres than a pivot. Increasing yield potential on more acres is the key to economic success these days.”
Frequency of irrigation is another advantage, according to Phene. “We can go across this field two to three times a day.”
Three more Netafim systems are being installed in the Missouri Bootheel and several more in Arkansas, according to Phene.
James, who plans to add more drip systems in the coming years, says in the future the system may provide other benefits including applying inputs through the tubes, provided such an application method is cleared by EPA.
“From pinhead square on, we make at least 10 trips through the field. We could reduce it quite a bit if we went through the drip system,” Allen said.