Digital Farming

Digital Farming header image
OSU's Tim Righetti and colleagues are helping growers increase their precision.

When I was growing up in a farming community in southern Oregon, I spent five summers working on a farm. I was hired to do one simple
chore: to irrigate 1,200 acres of barley and oats. I did everything I could to liven up this boring and seemingly endless job. That might mean racing the four-wheeler at top speed down narrow dirt roads and jumping it across ditches or any bump I could find. But I had to keep that to a minimum, for fear of breaking the four-wheeler. So sometimes I watched how the plants were growing.

I saw certain peculiarities. Year after year, they became more noticeable. The plants germinated faster in some fields than in others that had been planted earlier, and in some areas they didn't germinate at all throughout the entire growing season.

The growth pattern in one field, split in half by a levee, interested me. One side grew faster than the other. In other fields, the plants in certain spots would produce fuller and riper grain heads, even though every field was fertilized and watered equally.

Illustration showing aspects of digital farming.

Illustration: Tom Weeks

I never knew that these kinds of things were going to trigger a new kind of farming, one that used things like Global Positioning Systems,
Geographical Information Systems, yield maps, grid maps, soil samples,
aerial photographs, satellite imagery and defense satellites. What do these have in common? They all offer the potential of increasing crop yield and profits. And they're all part of a movement often called "precision farming."

"Precision farming is the capability to use management practices
appropriate for specific areas," explains Tim Righetti, a professor in
Oregon State University's Department of Horticulture who's experimenting with the approach.

A lot of the technology linked to precision farming isn't brand new. It's just becoming affordable. Much of it was developed during the mid-1980s in the Midwest. Here in Oregon, precision farming started gaining a foothold in the early 1990s. Today, "farmers spending $2,000 can get more computer power than was needed to send astronauts to the moon in 1968," says Righetti.

He offers an example of how farmers can benefit: Consider a 100-acre field that would require three tons of lime per acre to bring the pH (level of acidity) into a favorable balance. At $60 per ton, this would cost a grower approximately $18,000. "Wouldn't it be better to spend $1,000 to do a GPS (Global Positioning System) workup, do it more precisely, spend only, say, $15,000 on lime, and take the $2,000 left over and go to Hawaii?" says Righetti.

With GPS, farmers can pinpoint an exact spot on their fields, with help from U.S. defense satellites. With GPS and another device, called the Geographical Information System (GIS), farmers can use computers in their homes or offices to keep track of field data and create grid maps to make fertilizer applications and other farming activities more efficient.

Researchers standing on a large silver berry harvester.

A computer-equipped berry harvester at OSU's North Willamette Research and Extension Center near Portland. Photo: Bob Rost

"The first order of business in precision farming is yield monitoring,," notes Righetti. "The best way for growers to map their fields so that inputs can be properly and economically applied is to first learn how various sections of the field actually perform in terms of yield."

By recording the areas of lowest to highest productivity, a farmer can devote more attention to the less productive regions, the problem areas.

If the problem is unsolvable- for example, if a farmer comes across a gravel bar that is inhibiting growth-he or she can avoid wasting resources and devote more attention to productive and profitable areas. "It's only by yield monitoring that a low-yield area can be identified, mapped and then passed over when inputs are applied," says Righetti.

Imagine a farmer in a big, green John Deere tractor fertilizing a field: Instead of spraying the fertilizer uniformly, a computer in the tractor cab monitors the application. It applies more or less as needed. The plants get what they need more precisely, and the computer helps prevent over-fertilizing. All the farmer has to do is keep the front wheels straight.

Three men looking at a berry harvester.

Researcher Tim Righetti, left, and graduate students Craig Greenwald, middle, and Mike Halbleib on a berry harvester fitted with a Global Positioning System antenna and receiver wired to a scale. This allows them to pinpoint the yields throughout a field. Photo: Bob Rost

The farmer also can use the GPS for recording areas where soil acidity and fertilizer are low or high. By taking soil samples once every acre or every other acre, or wherever the farmer wants, he or she can plot each of those points with the GPS. Later, with the GIS, the farmer can create a map to use for future reference.

Righetti explains that "knowing one's location as samples are collected allows the user to evenly space the collection of samples in the field. Once these samples are analyzed, each analysis is assigned to its exact location." The farmer now has a clear understanding of a field's makeup. Precision farming has many other applications.

For example, in a study on Sauvie Island near Portland, OSU researchers are using the same technology to answer questions about a struggle between farmers and Canada geese. [See "A Goose on the Loose?" Oregon's Agricultural Progress, Spring/Summer 1998, page 30.]

On Sauvie Island, wheat grows well. Or at least it used to. But geese love wheat, and Sauvie Island is part wildlife refuge. With an estimated 180,000 of the birds using the island, and the number increasing, farmers are upset about perceived damage to their crops. Farmers in others parts of western Oregon are concerned about geese damage to their crops, too.

Bearded man standing next to an ATV in a field.

Movinir Louhaichi, an OSU graduate student in rangeland resources, uses a GPS device to map a wheat field scientists plan to monitor for geese damage. Photo: Bob Rost

Doug Johnson, Mike Borman and Movinir Louhaichi, all of the OSU
Department of Rangeland Resources, have been working with two
farmers and five fields of different sizes and shapes.

The researchers fence small exclosures in the fields so geese won't graze there. Then they use a harvester fitted with a GPS satellite system, plus aerial photography and other information, to compare yields where geese did and did not graze.

"We're hoping it will help the farmers get a clearer handle on things," says Johnson, noting that more precise knowledge of any damages could help public agencies decide how to handle the situation.

Another study involved a golf course.

"Aerial photos can show poor fairway irrigation distribution or accurately reveal the drainage layout on the green you just rebuilt," says Richard Matteson, a former graduate student in OSU's Department of Horticulture. "We were looking for a method that would allow us to
photograph turf plots and analyze differences using a computer."

Graduate student pulling wire from a cardboard box.

Craig Greenwald, a graduate student in agricultural sciences, rewires a GPS antenna that will be attached temporarily to a berry harvester. Photo: Bob Rost

An 18-foot advertising blimp and a balloon 6 feet in diameter with
mounted cameras seemed perfect for the job.

Aerial photography gave a better representation of the land than
ground-level photos in golf course maintenance. "The ground photo
showed what appears to be a good stand of grass emerging," said
Matteson. "But when contrasted against the aerial photos, the difference was striking. Dry and weak areas were apparent in aerial photos."

Aerial images and special software allowed the construction of maps that show the golf course's irrigation system along with other features such as drainage systems, bunkers, ponds and trees.
The researchers used a GPS unit for more precise pesticide application. Eventually, ground and aerial photos, GPS data and a GIS yielded a computer-based display of the entire golf course that could be used in decision making.

Tractor harvesting grass seed.

Grass seed harvest yield monitoring near Corvallis: The white device on top of the cab is an antenna. With GPS, defense satellites send signals to earth. A tiny computer in the combine uses the data to "triangulate" its position. Photo: Bob Rost

Aerial photos can help farmers, too.

"Linking GIS, image processing and GPS has tremendous agricultural
potential," says Righetti. For example, farmers might find it hard to
remember where weeds grew the previous year, but a computer can.
When it's time to apply herbicides, farmers can program locations to
receive either a high or low dose.

The use of such computer, satellite and aircraft-based technology is spreading. For example, Oregon pear and apple growers are using
precision farming techniques in an emerging approach to production
that's been dubbed "Integrated Fruit Management." The goal is to grow
fruit in a more consumer-oriented, environmentally sensitive and
cost-efficient manner.

Precision farming has been proven to work. So why haven't more
farmers jumped at the opportunity? "It's the learning curve," says

"If I were to let a student pay $2,000 more each term for tuition and take 12 credits more, would it be worth it? No, because that's just too much for the student to handle," explains Righetti.
In the case of precision farming, "technology is ahead of management," he says, adding that if farmers are interested in precision farming, they need to ask themselves the question, "Do I have the time and energy to make it work?"

According to Righetti, there is so much to precision farming that it is nearly impossible to learn on short notice. "Farmers shouldn't expect results right away," he says, "but for the future of their farms, they should go out, educate themselves and use the technology bit by bit."

Published in: Economics, People