OREGON STATE UNIVERSITY

Unmanned aircraft aims to simplify inventory for Oregon nurseries

03/07/2011

ORVALLIS, Ore. – It fits in the back of a pickup and looks like a hobby helicopter, but the aerial remote sensing system under investigation in the Willamette Valley soars high above traditional inventory methods of nurseries and Christmas tree farms.

Starting this year, a team of researchers from Oregon State University, the University of Florida and the University of Arkansas will test a new remote sensing system in three Oregon nurseries using an unmanned multi-rotor aircraft. The researchers hope the system will deliver real-time inventories of nursery and Christmas tree crops.

If so, growers no longer would need to estimate their inventory – or walk their fields to manually count thousands of trees or potted plants.

"Many in agriculture feel the unmanned aircraft could play a critical role in the future to monitor crop health and estimate yield," said Jim Owen, an OSU researcher. "The team hopes to also use the aerial system to measure plant size and recognize from above regions or patterns of crop stress."

The research, supported by grants from the Oregon Department of Agriculture and the Oregon Association of Nurseries, is expected to let growers know what's in stock and help predict future inventory, Owen said. "Nursery containers can be moved every day, and numbers change as plants are removed or sold."

The remote-sensing vehicle has four or more propellers and looks like a hovercraft. The research team used off-the-shelf technology to attach an every-day digital camera to the craft, which costs between $2,000 and $5,000 to make.

Although the vehicle is four feet by four feet and can be operated with a radio-controlled transmitter, it takes expertise to fly it and keep it within low-altitude limits, no more than 400 feet above ground level, Owen said. The craft also can be programmed to retrieve specific images at exact locations using GPS.

As images are collected, a commercial software program will be used that teaches itself to recognize individual plants and analyze the information, and then separates the plants from the background to provide a count. The team has already used this approach to count the number of citrus trees in a Florida grove, with an accuracy rate as high as 94 percent.

A portion of nursery license fees collected by the Oregon Department of Agriculture support the annual grants for this research.

"Oregon has a great reputation for high quality nursery stock," said Gary McAninch, supervisor of the department’s nursery and Christmas tree program. "Research helps the industry improve and maintain that quality while keeping Oregon competitive in the marketplace."

Until now, the research has been supported only by gifts from the J. Frank Schmidt Family Charitable Foundation. "We still have a long way to go," Owen said, "but the nursery industry is excited that this unmanned aircraft is cost-effective and could dramatically improve accuracy of inventory."

Sales of greenhouse and nursery crops in Oregon in 2010 was $561.6 million, second only to cattle in sales, according to information from OSU Extension. Oregon also is a major producer of Christmas trees. Oregon trees purchased to celebrate the holidays number more than any other state, about seven million each year.