Cotton seeding latest variable rate arena

Ted is Ted Sheely, Kings County, Calif., farmer who has added new meaning to precision agriculture within the last two years employing Global Positioning System (GPS) and variable rate technology to wide array of tasks from ripping to gypsum, nitrogen and Pix applications. This year’s variable rate technology was applied for the first time in the San Joaquin Valley to cotton planting and the agenda later this season calls for variable rate anhydrous ammonium applications and an attempt at aerial variable rate applications of a plant growth regulator.

The Sheely operation west of Lemoore, Calif., has become the test track for a wide array of precision ag technology involving everyone from NASA to the local agrichemical retailer. Much of it has been under a program called Ag 20/20, an ambitious partnership spawned by NASA to link USDA and various universities to growers to improve profits for commodity producers.

The idea is simple; develop new technology that will keep American farmers in business. Central to the idea is to use remote sensing to assist farmers in making key decisions during the year.

Sheely is an unabashed cheerleader for precision agriculture because as he sees it will be technology and technology alone that will keep him competitive in world markets where just about everyone he competes with has cheaper labor, water and other inputs and fewer regulations.

"I have to change the way I farm to stay in business," said Sheely, who has farmed on the West Side of the San Joaquin Valley for three decades.

Must be practical

However, those changes must make economic sense. University of California Cooperative Extension farm advisor in Kings County, Bruce Roberts, said the work at Sheely’s Azcal Management farm must be driven by practicality. Using new technology must be physically manageable and it must be affordable. "You cannot throw $2 at 50-cent problems," said Roberts.

"When I go to my banker and want to spend money on computers or tractor guidance systems it had better make sense and offer a return of $1.50 for every $1 spent, particularly in this agricultural economy," said Sheely, who farms cotton, tomatoes, pistachios, wheat, garlic, garbanzo beans and upland and Pima cotton.

So far he has been able to achieve that goal. Last year’s variable rate nitrogen trial saved him enough money on nitrogen to pay for the $7.50 per acre fee charges by Britz Fertilizers, Five Points, Calif., to sample, map and apply variable rates of N. The payoff was 50 pounds more cotton per acre with the technology.

He used a similar technology to apply the growth regulator Pix to four 160-acre cotton fields. Aerial photographs of the field detected various growth rates, and Hanford, Calif., consultant Nick Groenenberg went into those areas to determine how much Pix would be needed based on his plant mapping.

A ground rig equipped with Global Position System directed an onboard computer to apply either 18, 12, 8 ounces or no Pix to four different identifiable zones in the field. The computer could change the Pix rate in 20-foot increments.

Used less Pix

"I have never used 18 ounces of Pix in my life," said Sheely. "Tops for me has been 12 ounces.

"The bottom line is I used less Pix on those fields than had I use a one-rate fits-all like we normally do," said Sheely, the 1999 Farm West Western Farm Press/Cotton Foundation High Cotton Award winner. He saved money on Pix and is confident that final ginning reports will record a yield increase.

"Anytime you can improve uniformity in highly variable conditions, you are being more efficient with your inputs," said Sheely.

And uniformity is what he and the others in variable rate cotton seeding trials are looking for this year.

The goal is to mitigate high salinity levels in establishing a cotton stand.

Two fields were mapped with a mechanical salinity-measuring device called an EM38, according to consultant Brock Taylor of Clovis, Calif., who is working with California State University’s Center for Irrigation Technology (CIT) and others in the AG 20/20 project.

The device pulled down a furrow by a Spra-Coupe measures salinity down to four feet with a technology called magnetic induction.

Florence Cassel, CIT soil and water scientist, said the devise measured salinity across 100 feet of rows and every 30 feet down the measuring row.

The readings were mapped and put into an onboard computer that regulated the seeding rate from the planter via a hydraulic motor.

Tim Stone, precision ag coordinator for Britz Fertilizers, said the fields were divided into three salinity zones and 10-, 15- or-18 pound seeding rates, the later for the highest salinity readings.

The GPS Beeline tractor guidance system on board the tractor told the Raven AMS computer exactly where the tractor was in the field. The salinity map downloaded into the computer then managed the seeding rate.

Maps fields

Dan Wiens is precision farming coordinator for Britz and maps fields based on information gleaned from satellites, aircraft or from devices like the salinity measurement apparatus developed by CIT.

These maps, he said, save time by identifying variations by pinpointing where differences are and then putting people in the field to find what those differences are so a farmer can correct them.

Stone said he has used variable rate technology on about 4,000 acres since Britz began offering precision ag services.

The interest in variable rate technology, said Roberts, has been on the most highly variable fields. That is not unexpected, but he anticipates as growers like Sheely get results from it, it will grow.

"What we are doing at Ted’s is putting a value on this technology," he said.

"When prices for what farmers produced were higher than they are now, they were operating in a well-buffered environment. Prices no longer offer that buffer," said Taylor. Profit must come from new technology.

Variability is evident to farmers like Sheely. "But variability is not in one spot. It is spread all over a field," he said.

What this new technology offers is a way for the farm owner to better mitigate variability without personally riding a tractor.

"The people who work for me see that variability just like I can, but I don’t want them making decisions visually…it is not right to expect them to do that because they do not have to go to my banker and deal with the financial aspects of my farm," said Sheely. ‘I do not want to put that responsibility on my tractor drivers."

"I don’t have time to drive a tractor…I have to worry about water and so many other issues off the farm that effect my farm," he said.

However, he knows what goes on that tractor impact his bottom line as much as every other aspect of his farm.

He now owns five Beeline GPS guidance systems. He’s already realized a 30 percent savings in disking and ripping because the satellite-guided tractors are more efficient.

Quicker, more accurate

His employees can operate equipment at night and they can spend a longer day in the tractor without mental fatigue. "We planted our cotton in 10 days this year rather than the normal 14. The men knew it meant overtime, but they were willing to do it because they knew we would get finished quicker and it would be accurate."

Tractor drivers quickly embraced the new technology, said Sheely.

"It was interesting, we had a Beeline-equipped tractor in the shop for repairs, and the guys kept asking when we were going to get it back," he said.

"We have a profit sharing plan for the people who work here, and they knew that the Beeline system allowed them to be more efficient and hopefully improve the bottom line," said Sheely.

Wiens put precision agriculture in perspective when he said it mimics early-day valley farming.

"When farmers were farming hundreds of acres instead of thousands like today, they knew their fields and made what we today call variable rate applications. When they were spreading manure, they know where the bad spots were and put a little extra on there," said Wiens. "Grandpa practiced variable rate technology, they just didn’t call it that.

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