Variable rate application technology has been around for a few years. The real innovation, says Alabama farmer Neal Isbell, is that the technology now is farmer friendly, and it works.

Isbell, who farms in north Alabama's Tennessee Valley, shared his experience with variable rate technology during the recent Beltwide Cotton Conferences in San Antonio. He has been farming for 34 years as part of a fifth generation farming operation in north Alabama. With the help of sons Todd and Shane, Isbell farms 3,600 acres of cotton and 1,000 acres of corn.

Variable rate spraying, says Isbell, isn't exactly new technology. “A lot of people have been working with this technology for several years now. The system that gets this technology to the farm is what I consider to be so innovative. We are working with InTime, Inc., a company based in Cleveland, Miss.,” says Isbell.

The system is innovative for cotton production, he says, because you don't have to be a computer expert, and you don't need a computer expert on staff to make the variable rate system work on your farm. “The process works something like this,” says Isbell. “First, you identify your field boundaries, and InTime sets you up on their Web site. You have a password to get access to your information. Next, you set up your sprayer. If you start from scratch, the cost will be from $6,000 to $8,000. If you're already doing some precision work, you'll have some of the parts and software that you'll need to set up the system.”

InTime, says Isbell, flies over your fields to acquire usable images. “This is a vital part of this system, and without images — excuse the grammar — you ain't got nothing. Once the images have been acquired, then InTime processes and places them in your file located on their Web site. Now, you're ready to begin,” he says.

You can go on-line, he says, and request a scout map. This map will show seven different growth levels, with one being the lowest and seven being the highest. At this point, the farmer has the option of viewing a map and making decisions on spray rates or uploading the map onto an iPAQ to carry to the field.

“This map is geo-referenced so you can go anywhere in the field to determine which rate you want. Now, you make the decision of which gallon-per-acre rate you want to spray on the seven different levels,” says Isbell.

The request to create a “prescription” for spraying is done over the Internet with a simple form, he says. “Last year, I made a request once and it took about one or two minutes for the server to return the request. Once this is done, you download the prescription and move it to the sprayer. Then, we look at the prescription report to help us decide which spray tips to use and which rate of chemical will be in each gallon of water.

“This is somewhat different from what we've done in the past. For example, when using growth regulator, we run 1.1 ounces per gallon of water. The 10-gallon rate-per-acre will spray 11 ounces of growth regulator per acre. We use the 1.1 rate because it works out to 7 gallons. On a 4710 with 800 gallons of water, we put out 7 gallons of material, which equals 896 ounces. That works back to 1.1 ounces of material per gallon.

“We did not see a big savings in material costs, but we were able to put the chemical where we wanted it. And, more importantly, we didn't spray where we didn't need to spray. You also can generate a map showing where the different rates will go out,” says Isbell.

Once you have reached this point, you can hit “Go” on the iPAQ and spray, he says. “The amazing thing to me is that it actually works. You stand back and watch the sprayer change rates or it can even cut on and off on its own. As you spray, you'll get a map on the iPAQ that tells you what you've sprayed or, better yet, what you haven't sprayed.”

Isbell used this same system to make variable applications of defoliant and boll opener.

“We didn't see much of a savings on defoliant, but we did see a big savings on boll opener. In addition, we were able to put higher rates where needed to get the whole field ready to pick. Last year, about half of our crop was with InTime. This year, we plan to put our entire cotton crop into this system. For 2004, we plan to make some variable rate applications on side-dress nitrate, insecticide sprays for plant bugs, growth regulators and defoliants. We'll especially be interested to see how it does with growth regulators.”

Last year, says Isbell, InTime did some aerial variable rate applications. “We hope to have the option of using aerial application in the Tennessee Valley for 2004. We think this innovative approach will be one of tomorrow's solutions for today's challenges.”