A successful result may not be limited to water conservation.
“The end product is hopefully an irrigation tool that will help water use efficiency — and produce better quality produce,” Frame said.
There is the possibility overall water use will not be reduced, he said.
“Growers might actually increase tonnage,” Frame said. “Even utilizing water use efficiency tools could increase water use, but on a per tonnage basis, it would be less.”
If all the pieces of the puzzle come together, the project will be able to project crop specific ET rates on plots of land as small as 100 feet by 100 feet, less than one-quarter of an acre.
“In practice, the information will be most useful for farms of five acres in size or larger,” Melton said.
With the exception of some wine vineyards, nearly all California farms are a minimum of 20 acres.
A limited pilot project is under way this year. A more aggressive project is planned for 2011 and will focus on the San Joaquin Valley.
“We’re currently working with Western Growers, the USDA, and partner-growers to identify specific locations for deployment of wireless sensor networks designed to support evaluation of satellite-based estimates for different crop types,” Melton said. “The crop coefficient and ET maps for the San Joaquin Valley region will be available for all growers to review and evaluate.”
Key to the project’s success will be the participation of some non-coalition members, Salas said.
“If growers actively participate, they can actually see the advantages of the technology,” she said. “Their involvement will be critical.”
Mapping of crop coefficients and estimation of crop ET can be done directly from satellite information in combination with ET estimates from CIMIS, Melton said.
“However, grower participation is critical to evaluating these estimates,” he said.
Where the growers enter the picture is when scientists and the computer program attempt to translate estimates of crop ET into irrigation system run times, Melton said. That requires additional input from growers.
“We also believe that working closely with growers is the best approach for transitioning this work from a successful research effort to a system that provides useful information to growers, and that can assist growers in getting the most value out of the water they have available,” he said.