A satellite image of the Lemoore area with crazy patchwork of reds, yellows, greens, blues and pinks might not mean much to the average viewer.

To Tim Stone, it's a key toward unlocking the secrets of Kings County's vast agricultural acreage.

Welcome to the world of aerial imagery -- satellite, airplane and even remote-controlled drone -- that is helping a new generation of growers get even more out of their fields.

Stone's official title is precision ag coordinator for Britz-Simplot in Five Points, a lonely agricultural outpost in the vast Westside fields of Fresno County. Among other services, he provides aerial images for a price, all the way from $1.75 an acre for basic satellite pictures to $3.75 an acre and up for high-resolution airplane photos that can get down to the detail of individual plants.

Ever see a corn or cotton field with the plants growing at different heights?

Aerial imaging is designed to prevent that by telling farmers exactly where their fields need more fertilizer or other additives to achieve uniform productivity and yield across a given plot.

It's hard for growers to visually see what's going on from the ground, especially in large fields.

Westside grower Tim Larson ties aerial photos from airplanes to soil samples on the ground that show where more nutrients are needed.

"There's a bunch of different things (it) can tell you. I know where the crops are growing more lush," Larson said.

Farmers have long used variable rate fertilizer applicators to even things out.

But people in the industry are hoping similar technology will one day apply to irrigation.

The vision is that growers will be able to identify areas with high or low water needs with data transmitted to their computers and, using either a drip or sprinkler system, adjust irrigation levels based on the data.

The technology could be particularly useful to farmers facing waters shortages and an ever-increasing need for conservation.

At the moment, there's no way to adjust microsprinklers or drip lines to apply different amounts of water at each emitter. Every nozzle gives the same amount. So growers adjust by adding more sprinklers/drip emitters at certain spots, or by adding additional water lines.

The ideal would be to take a soil map, figure out exactly how much water each part of a field requires, and match it up, Stone said. The soil maps are already available. But more precise technology may be on the way.

U.S. Agriculture Department scientists are working on a system of remote ground sensors that, when combined with aerial imagery, would allow farms to make daily irrigation adjustments.

Farmers are doing a better job of "ground truthing" -- understanding exactly what the image is saying about actual field conditions, said Larry Schwankl, a University of California Cooperative Extension irrigation specialist.

Schwankl called aerial imagery "one more tool" as water becomes more valuable.

Efforts are also being made to improve the imaging beyond what a small aircraft can provide from 4,000 feet. The idea is to develop remote-controlled aircraft that can fly slow and low to take more accurate pictures.

Federal Aviation Administration restrictions make it difficult to operate such "drones," according to Stone.

But farmers, especially those on the large-scale Westside, see a future for the concept.

"I think there's probably some merit to that. We've seen a lot of changes in the last 10 years," Larson said.

The reporter can be reached at 583-2432.

(Sept. 25, 2009)