Irrigation on the Small Side

By Boyd Kidwell
Progressive Farmer Contributing Editor

Buddy Rivers wouldn’t be farming the way he does without pivot irrigation rigs. During the past 30 years, he and his father, Bud, installed pivots on the larger fields of Rivers Farms, near Sumter, S.C. Now, Rivers and his son J.T. “John” Rivers IV are installing small-field pivots on highly productive fields of less than 60 acres.

“Irrigation is the best thing to happen in my farming career,” Buddy says. “Years ago, we gave up cotton and peanuts, and switched to a corn, wheat and soybean rotation. We can’t grow profitable grain crops year in and year out without irrigation.”

Rivers Farms now has 31 pivots covering 85% of 2,000 crop acres. John graduated from Clemson University six years ago and oversees many of the irrigation-management duties. The Rivers grow 1,000 acres of corn and 1,000 acres of soybeans double-cropped behind 1,000 acres of wheat.

Lindsay Zimmatic 7500P Small-Field Pivots are the newest tool in the Rivers’ expanding toolbox. Rivers Farms was one of the first operations in the Southeast to install a small-field pivot, and the Rivers plan to install additional rigs. Small-field pivots make it possible to irrigate fields of 60 acres and less. Rivers’ small-field pivot covers 25 acres.

“Years ago, we placed full-sized pivots on some smaller fields, and we’ll eventually replace them with small-field pivots now that these are available. Because they’re lighter and don’t require as much water volume, small-field pivots don’t cost as much to install and are cheaper to operate,” Buddy says.

Big Boost From Small pivots. Small-field pivots range from 600 to 800 feet long and have the same clearance (101⁄2 feet) as full-sized pivots to irrigate 12-foot corn. The Zimmatic 7500P has a 41⁄2-inch waterline that delivers 250 to 400 gallons per minute, explains irrigation specialist Benny Altman, of Sparrow and Kennedy Tractor Co., in Bishopville, S.C. Small-field pivots use the same drivetrain and gear boxes as the standard Zimmatic pivots.

Rivers Farms’ corn averages 185 bushels per acre, but irrigated acres produce 225 to 250 bushels per acre. “It’s a shock to watch the combine yield monitor drop from 250 bushels per acre in the irrigated area to 50 bushels per acre in a dryland area. It makes you realize the value of irrigation,” Buddy says.

lofty goals. In 2011, South Carolina’s state average corn yield was 65 bushels per acre, the lowest in the U.S., according to USDA. South Carolina corn growers averaged 91 bushels per acre in 2010 and 111 bushels in 2009. The average corn yield in the U.S. was 147 bushels per acre in 2011.

After watching his yield monitor show yields of 260 bushels in irrigated corn, the Rivers have set high goals. “With today’s hybrids and optimum seeding rates [32,000 seeds per acre], my goal is to average 300-bushel corn over our irrigated acres,” 28-year-old John says.

The combination of irrigation and new varieties makes soybeans pay off for Rivers Farms, too. The Rivers harvest wheat and plant soybeans in June. With pivot irrigation and new varieties, double-cropped beans average 55 to 60 bushels per acre. Without irrigation, most farmers are fortunate to produce 30-bushel beans behind wheat.

“With today’s soybean varieties planted behind a 70-bushel wheat crop, we can gross $1,000 per acre on double-cropped beans and wheat,” Buddy says.

Bright futures. Irrigation is also a key part of Brent Crapse’s farm operation. The 30-year-old farmer, from Hampton, S.C., is counting on small-field pivots to play a big role in the future. Crapse and his father, Ray, plant corn, peanuts and cotton under the pivots.

During the past 10 years, Brent and Ray have installed nine full-sized pivots covering 600 acres of land they own. When Valley Irrigation launched its 5000 Series small-field pivots in 2010, the father/son partners pounced on an opportunity to boost yields on small fields.

“Irrigation doubles our corn yields in South Carolina and takes much of the risk out of growing peanuts plus increases yields,” Brent says.

Many South Carolina farms were hurt by a severe drought in 2011, and Brent reports dryland corn yields were less than 50 bushels per acre. At the same time, his irrigated corn produced more than 200 bushels per acre, and irrigated peanuts yielded 5,000 to 5,200 pounds per acre.

Installing small-field pivots costs $2,000 to more than $3,000 per acre, Brent explains. His estimates include the cost of the pivot, drilling a well and paying the power company to run electricity to a control point for the pivot. The cost of the small-field pivot itself is approximately $1,200 per acre, says irrigation specialist Tyler Fields, of Guess Irrigation, in Hartsville, S.C.

Even with higher yields, the cost of irrigation doesn’t always pay off. In a 38-acre field where the pivot makes a full circle, Brent estimates the cost of installing a small-field pivot at $2,100 per acre. However, the Crapses couldn’t justify the investment on another small field where a pivot couldn’t make a full circle. The field would cost $3,500 per acre.

“We really wanted to put a pivot on a small field near our shop that we drive past every day. This is thirsty [sandy] soil, and irrigation would really bump the yields, but $3,500 per acre is too much,” Brent says.

Valley Series 5000 Small-Field Pivots have an advantage over larger pivots because they use single-phase electric power to run a submersible pump that supplies a 5-inch waterline. The larger 7000 Series pivots require three-phase electricity.

“We plan to install three or four more small-field pivots and try to get them paid for while commodity prices are relatively high. There’s nothing like irrigating your own land,” Brent says.

Smartphone Control. John Rivers uses his smartphone to control and monitor Rivers Farms’ pivots.

To make remote control possible, Rivers subscribes to Lindsay’s FieldNet (www.lindsayfieldnet.com) pivot-control system. The subscription fee (including cell phone control) for FieldNet is $200 (suggested manufacturer’s list price per pivot) for a four-month irrigation season.

Crapse uses Valley Tracker Mobile to monitor and control pivots with his smartphone and by computer. The Tracker communications plan costs $1,900 (depending on model) for equipment and installation plus $24.95 per month (per pivot) for a four-month subscription (suggested manufacturer’s list price). There is a monthly charge of $9.95 during the irrigation off-season.

For a demonstration of pivot control with smartphones, visit m.valleytracker.com.

(BAS)

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