Can auto-steering with RTK correctional signals for sub-inch accuracy pay their way? And, can GPS-based automatic on/off of planter row units and spray boom sections earn their keep through minimized skips and doubled-up applications?

Return on investment (ROI) for site-specific farming is site-specific in itself. You can't necessarily go by what your neighbor or a grower in the next county saves or doesn't save by investment in this technology. ROI depends on field size; field shapes; field features (water-ways, etc.); crop prices; input costs; equipment width; number of “applied acres” (how many times the same acres will be covered by application equipment guided by the technology); and percent reduction in overlaps compared with whatever guidance system the technology replaces.

So, how do you sort it out?

Farmers have formed their own groups to to help with that. The groups are where farmers can come together to compare notes. One is NeATA, the Nebraska Agricultural Technologies Association. Another is KARA, the Kansas Agricultural Research Association. PARA, the Precision Agriculture Research Association in Montana is yet another. Their funding generally comes from grower dues and annual conferences. Officers are primarily growers.

SEVERAL FARMERS AT the NeATA conference who are using one or more of the technologies for RTK auto-steer guidance, automatic spray boom shutoff and auto row-unit shutoff cited such benefits as: being able to run more hours per day because of less fatigue and ability to run after dark; reduced chemical waste and more field efficiency. But these Nebraska growers said it was difficult to put ROI numbers to their investments in the technologies.

Precision agricultural technologies' value “increases tremendously” with high input costs and corn prices, says University of Nebraska-Lincoln agronomist Richard Ferguson. But, quantifying those benefits can be elusive, even for precision ag technologies such as yield monitors, field-mapping and variable-rate technologies whose genesis traces back 15-20 years, according to Ferguson.

Maybe one of the most specific ways to get at ROI for auto-steering and automatic boom/row unit shutoff is an online Excel spreadsheet developed by Kansas State University (K-State) ag economists Kevin Dhuyvetter and Terry Kastens, along with Dietrich Kastens. Go to: www.agmanager.info/farmmgt/machinery/Tools/KSU-GPSguidance.xls.

Marvin Batte, Ohio State University professor of farm management, tackled the ROI question on GPS-based auto guidance and auto spray-boom control for several spray-boom widths on three shapes of 100-acre fields, each with and without two grassed waterways (six different field situations).

Analyses he did in 2006 show average input savings for the six fields ranged from around $2/acre for a 60-ft. spray boom on a 600-acre farm to $2.40/acre for a 120-ft. boom on that size farm. His analyses show return over cost of the technologies (including fixed costs) ranging from a negative $2.72/acre for a 60-ft. sprayer on a 600-acre farm to a positive return of $1.15/acre for a 120-ft. sprayer on a 2,400-acre farm. When updated with 2008 fuel and chemical costs, the net returns ranged from a negative $1/acre to a positive $3.19/acre for the 600- and 2,400-acre farms, respectively, says Batte.

Cost/benefit analyses such as Batte's or spreadsheets such as K-State's are good ways for growers to get at investment decisions on GPS-based auto-steer and auto-boom section/row unit shutoff technologies.

Precision ag organizations such as KARA, PARA and NeATA offer growers an opportunity to compare reliability, compatibility and services from the various technology providers.

KARA

Kansas Agricultural Research Association President and Herndon, KS, farmer Dietrich Kastens (Terry Kastens' son) says the group's goal is to enable “farmers to better assess the economics of adopting precision ag technology and site-specific management.”

KARA began as an informational group linked with K-State. But in the late 1990s, it became a member-supported group with financial support coming primarily from member dues, says Kastens. The group was organized “because so much was hitting us so fast in the late 1990s.”

Members began to ask themselves, “How can we make money with this stuff?” Kastens says. The organization now sponsors an annual precision ag conference, a biennial field day in Kansas (held in Oklahoma in alternate years), need-driven workshops and on-farm research, according to Kastens. Roughly three-quarters of KARA's 70 members are growers, while the rest are industry representatives and university personnel.

KARA will help a grower who wants to set up a precision agricultural technology trial on his or her farm with a “little money,” and will help identify appropriate university researchers and companies in setting up the trial. With so much competition for a grower's time, that kind of assistance can be helpful, he notes.

Visit KARA's Web site at www.ksagresearch.com.

PARA

The Precision Agriculture Research Association in Montana was one of the first precision ag technology user groups in the country, says Christine Sommers-Austin, a Montana State University (MSU) contact for PARA.

Funding for PARA first came mainly from a USDA research grant through MSU for application of GPS and space technologies (i.e., remote sensing) from NASA through MSU and the Upper Midwest Aerospace Consortium (UMAC).

PARA, with its early emphasis mainly on remote sensing for farmers and ranchers, consists primarily of Montana growers, says PARA President Darin Arganbright, a Carter, MT, grower. (He can be contacted at 406-734-5286.)

NeATA

NeATA Past President and Giltner, NE, farmer Brandon Hunnicutt says the Nebraska association isn't just for tech-intense farmers. “We pull guys together with different levels of technology experience. It's a good place to exchange ideas on what works and what doesn't.”

NeATA is “the glue to bring together groups of farmers with common interests (in precision agricultural technology),” says Dave Varner, a University of Nebraska Extension educator and secretary/treasurer of the organization. “They come to the conferences because of networking and contacts there.”

About 125 farmers, researchers and precision ag vendors attended NeATA's annual conference in Grand Island last January. It's a social networking approach, according to Varner. NeATA began as a precision ag technology organization about nine years ago, in which farmer, researcher and technology vendor dues for support of the organization are incorporated into registration fees for the organization's annual technology conference. The conference includes presentations by users, researchers and vendors. Its Web site is www.NeATA.org.

NeATA President Lon Bohn, who farms with brother-in-law Don Blaschko as B&B Partners near Gibbon, NE, sees the organization as a venue that can provide an unbiased evaluation of precision ag technologies. Through organizations like this, growers can make their needs better known to researchers and providers, he says.

Sometimes, it's difficult to see where this technology will lead you and how it will pay off, Nebraska grower Bohn says, pointing to the following example in his and his brother-in-law's operation.

Several years of yield mapping and aerial imagery revealed a bigger problem with irrigation water distribution under center-pivot irrigation than they initially believed. This was on pivot circles where part of the circle is level and part is sloped. The yield mapping and aerial imagery led them to adopt strip-tillage as a solution.

That tillage system has not only saved them a couple of irrigations worth $1,500-2,000 each in a season, but has reduced erosion, as well. “And, what value do you put on reduced erosion?” Bohn asks rhetorically. It's an example of how precision ag technology can lead to benefits you may not always foresee.