MISSISSIPPI STATE – A new app is being written to help farmers properly calibrate sprayers, an involved process with the potential for making mistakes.

The Mississippi Soybean Promotion Board gave a $10,000 grant to the Mississippi State University Extension Center for Technology Outreach and the Department of Plant and Soil Sciences to develop an app to help with this process. An app, short for application, is a computer program that runs inside another service. This app will run on Apple Operating System, or iOS, devices such as the iPhone, iPad and iPod touch. Similar apps on other platforms are planned.

Dan Reynolds, a Mississippi Agricultural and Forestry Experiment Station and Extension researcher is co-principle investigator on the project. He said chemicals are frequently misapplied on farms because of improperly calibrated sprayers.

“Proper calibration and use is important for any application of pesticide, herbicide, fungicide or fertilizer,” Reynolds said. “Farm chemicals are often over- or under-applied. This can cause crop damage when too much is applied, or the chemical can be wasted when too little is applied.”

Reynolds said there is a two-step process to making a proper chemical application through a sprayer.

“First, you must check the flow rate to see that the piece of equipment is putting out the correct amount of water,” Reynolds said. “Second, you must make sure the correct amount of chemical is in the tank.”

Many tractors are computerized and calibrate their equipment automatically. Others must be manually calibrated. The app will help producers with these calculations, whether to check the onboard computer or to calculate needs for manual control of the spraying.

“It doesn’t matter if it’s a hand-held sprayer or a 120-foot boom on a commercial sprayer,” Reynolds said. “Proper dispensing of chemicals requires proper calibration, which means you have the proper flow and the proper chemical mix. Each nozzle is responsible for covering a certain area of earth. It’s all about the flow of water coming out of the orifice and the proper mix of chemicals coming from the tank.”

Kelli McCarter, an Extension applications developer, will write the code to develop the app. She is working on the project with Reynolds; Trent Irby, Extension soybean specialist; and Jamie Varner, an Extension instructor and co-principle investigator on the project.

“We start by talking to the experts to understand the subject matter and gather the information we need,” McCarter said. “We do research to understand what the user needs the app to do. Apps must be very intuitive.”

This app will require the end user to enter a variety of inputs, such as orifice size on the spray tips, spray pressure, speed of the tractor, chemical quantity and tank size. The app will use these figures to calculate proper calibration for the sprayer.

In early September, the team went to the Blackbelt Experiment Station in Brooksville for some hands-on learning about how a sprayer operates and what must be done to calibrate one correctly. This information will prepare them to create the app.

Randy Loper, director of the Extension Center for Technology Outreach, said the Extension Service is getting into the apps business because of the pressing need for them within agriculture.

“There is limited availability of commercial software for agriculture, and we have received a great deal of interest from our stakeholders for apps,” Loper said. “The Soybean Promotion Board generously stepped up to the plate and gave us funds to help develop this calibration app.”

When complete, the app will be available as a free download from the iTunes store.

Varner is helping to gather the information that will be used to develop the app. Once it is available to users, she will provide customer support to users.

“Our focus is on supporting the agriculture industry,” Varner said.

The sprayer calibration app will be the second app the MSU Extension Service has developed. McCarter said the first app calculates break-even prices for livestock and is expected to be released soon.