The most commonly used method of irrigation scheduling has been based on the feel of the soil, the researchers note, which provides no quantitative measure of crop or soil water status. Studies have shown that more than 25 percent of producers base their decision on when to start irrigating on what their neighbors do.

Sensors can also be placed in the rooting zone to measure soil moisture during the growing season. As the plants grow and remove moisture from the soil, depletion below a certain level indicates that irrigation is needed.

While sensors are accurate if properly installed and maintained, they can be expensive, difficult to install and time-consuming to read and record data regularly, and so the researchers did not want to rely on them.

Wise water management requires knowledge of how much water the crop needs and when the water is needed. Irrigation scheduling is a method of managing water to better match the timing and application of irrigation with crop water use.

In high-rainfall areas, like Mississippi, the uncertainty of amount and timing of rainfall makes irrigation scheduling particularly challenging, since a high rainfall event immediately following irrigation can result in waterlogged soils that impede crop growth.

The challenge for Mississippi producers is to manage water resources appropriately and provide sufficient water for crop production during the droughty periods that occur during the growing season, the researchers note.

“Particularly critical to the continued success of agriculture in the Mississippi Delta is the development of accurate and easy to use guidelines for irrigation scheduling and application.

“From previous research, we know that farmer acceptance of new technology is often predicated on their accessibility to scientists and Extension personnel. A significant component of our research is to develop educational tools to enhance understanding and adoption of the new technologies.

“The most important indication that a tool is considered worthy by producers is that it gets used.”

To that end, they have focused on several key points in developing the irrigation tool:

—It must be easy to use, understand, install, and update.

—Data requirements should be minimal.

—Data collection should be as “invisible” as possible through automatic downloading of information such as weather data.

—It should seamlessly integrate with other programs, such as recordkeeping, conservation, etc.

—It should be acceptably accurate, given the data input.

Field and irrigation system data must be entered by the producer. Scheduling is arranged by water source to allow the coordination of fields serviced by particular wells.

The irrigation scheduling Web site would be operated by the Mississippi Extension Service and maintained at Mississippi State University.