Two small, remote-controlled aircraft are expected to start flying over potato fields in the Hermiston area this month as part of Oregon State University's efforts to help farmers more efficiently use water, fertilizers and pesticides to bolster yields and cut costs.

While taking photographs, the aircraft will fly over 50 acres of OSU's 300-acre Hermiston Agricultural Research and Extension Center (HAREC), as well as several crop circles totaling about 1,000 acres at a research cooperative farm west of Boardman. The flights will take place at least three times a week until the potatoes are harvested in the fall, beginning with a test run Wednesday at the Boardman farm.

OSU researchers will use various cameras on the aircraft to photograph the potato plants. The cameras will include ones that detect different wavelengths of light. One of these wavelengths, infrared, is reflected by plants, but unhealthy plants reflect less of it, and in infrared photographs sick plants are much darker. Researchers will also explore using other wavelengths of light to determine which ones will be most helpful in identifying troubled plants.

Researchers aim to see if the cameras, which are capable of zooming in on a leaf, can detect plants that aren't getting enough fertilizer and water. They'll purposely reduce irrigation and fertilizer on some plants and will then see how quickly, if at all, the equipment detects the stressed plants. If it works, the scientists hope that the project will continue in subsequent years so they can test the cameras to also find plants that are plagued by insects and diseases. The idea is to help farmers take action before larger crop losses occur and it becomes more difficult and expensive to control the problem.

"The key is to pick up plants that are just beginning to show stress so you can find a solution quickly, so the grower doesn’t have any reduced yield or quality issues," said Phil Hamm, the director of HAREC. "This in turn can save money. It's an early warning system for plants with issues as well as an opportunity for growers to reduce costs by being more efficient in water and fertilizer use."

Potatoes were chosen as the focus of the research because they're a high-valued crop, expensive to raise and must be carefully managed to reduce internal and external blemishes and irregular growth spurts, said Don Horneck, an agronomist with the OSU Extension Service. One of Oregon's leading crops, the state's farmers sold $173 million of potatoes in 2012, according to the U.S. Department of Agriculture. But spuds are prone to devastating problems caused by diseases and insects, said Horneck, who is the lead researcher from OSU on the project.

"They are one of the most difficult and expensive crops to grow," he said, adding that it typically costs Hermiston farmers $4,000 or more per acre to grow them. That equates to about $500,000 for the average size of field in the area.

OSU hopes that the aircraft it tests will reduce these costs. The aircraft that will fly over OSU's land is called a HawkEye and is sold by a company called Tetracam. About the size of a suitcase and weighing only eight pounds, its maximum flight time is 10-30 minutes. The hull-less, battery-operated machine is easy to operate and was made for farmers with plots of land that are less than one square mile. A motor and propeller allow it to take off on four wheels. A parachute keeps it in the air.

A delta-winged aircraft made of plastic foam will fly over the private farm. Made by Procerus Technologies and called a Unicorn, it has a wingspan of no more than six feet and weighs less than six pounds. A bungee cord launches it like a slingshot.

OSU is inviting the public to see the HawkEye fly during its potato field day at its Hermiston research center on June 26.

Allaying concerns about privacy, Hamm said, "These unmanned aircraft are for agricultural research only and will be used to do nothing more than that. This is about helping our local growers do a better job of growing crops, something HAREC has been doing for the past 102 years."

The Federal Aviation Administration has authorized the flights of the aircraft, which aren't allowed to fly higher than 400 feet and must stay within sight of the operator, typically less than a mile away.

OSU is leasing the aircraft from Boeing Research & Technology. n-Link, an information technology firm in Bend, is also a partner in the project. Ray Hunt, a plant physiologist with the USDA in Beltsville, Md., will collaborate with OSU's Horneck on the data analysis.

OSU aims to become one of the nation's premiere universities using unmanned aircraft for research. It is using or has plans to use them in studies on natural resources, wildlife, land-use management, forestry, oceanography and engineering.