How OptiGro Can Help With N-Deficiency

Cindy Zimmerman

KCIMCrop stress associated with nitrogen deficiency is showing up in some fields in the Midwest.

Tracy Blackmer, an Iowa farmer who is director of research for the Iowa Soybean Association, recently talked with Neil Trobak of KCIM in Carroll, IA about the situation.

“We do a lot of field research projects around the state focusing on nitrogen in corn,” said Blackmer. “Last year we had over 250 replicated nitrogen trials that we collected yield data on and over 1000 fields that we evaluated with aerial imagery and stock nitrate.”

BlackmerIt has been a wet spring in Iowa and Blackmer says one of the biggest issues with nitrogen management is the amount of spring rainfall. “When you have enough rain to move the soil profile, the nitrate will leach out with that water.”

With rainfall this spring in western Iowa well above normal, Blackmer says they have seen a lot more nitrogen stress in corn fields than normal, which means growers should be doing late spring soil tests and monitoring their crop carefully.

“Aerial imagery is one of the better tools that will let people evaluate the entire field at one shot,” he says. “Nitrogen stress doesn’t show up uniformly across the field and an aerial image will let you look at the entire field and see any small part of it at any point in time.”

Blackmer says John Deere’s OptiGro system is one tool that provides aerial imagery and processes it so a grower can see the amount of N-stress in the field and exactly where it is located. “So a grower can go in and actually go in and correct the N-stress with equipment at any point in the field.”

“With the high price of corn right now, this is something people really want to watch closely for the bottom line.”

More information about OptiGro can be found on-line from

Listen to MP3 KCIM interview with Blackmer (4:30 min mp3)

Audio, Farm Broadcast Reports, General

Producer Profile: Steve Hafner

Melissa Sandfort

The Precision in Practice column brings you the latest reports from producers across North America who have put precision farming into practice in their own operations. Visit this column regularly to see what your neighbors are saying about precision farming and how they use it on their farms.

Short broadcast interviews with these and other producers can be found in the Precision Ag Minute archives.

corn.jpg Steve Hafner
Leroy, MN
2,200 acres of corn and soybeans
John Deere components used: Starfire RTK

Q: How do you utilize your guidance system?
A: I strip till in the fall, place dry fertilizer, build a burm and record all my passes. I put the data card in, come back in the spring and plant right on the fertilizer I just placed the fall before, on the same exact tract. The repeatability is a necessity. It also takes the fatigue out so I can watch the implement work.

Q: What system would you recommend?
A: For my operation and no-till/strip-till when you need repeatability and the ability to stay in the same track, I’d recommend RTK. For someone doing the same work I’m doing, I would go right to the RTK system – I wouldn’t start out on a “lower,” less expensive system. Within a year, I ended up with RTK because it’s that much more accurate.

Once people see what it does, it sells them. It almost has to be experienced to be fully appreciated. Guidance systems have just cracked the tip of the iceberg with what they can do now compared to what they’ll be able to do down the road.

Precision in Practice

N Losses May Affect Growers

Melissa Sandfort

Poplar Grove, IL 2 NDVI.bmp The issue: Nitrogen deficiency stress in corn due to heavy rainfall and other factors in the Midwest this spring which may soon become more apparent in the next few weeks to put the corn crop at risk and reduce yields.

What does that mean?
1. N losses always exist.
2. Mineralization always exists. This year will probably more erratic than usual.
3. The heaviest N use begins at row closure. Imagery allows you to asses the nitrogen situation. If necessary corrective action can still be taken this year.

The solution? The OptiGro system from John Deere Agri-Services that allows growers and fertilizer dealers to assess and adjust mid-season nitrogen management.


Producer Profile: Randy Reznicek

Melissa Sandfort

The Precision in Practice column brings you the latest reports from producers across North America who have put precision farming into practice in their own operations. Visit this column regularly to see what your neighbors are saying about precision farming and how they use it on their farms.

Short broadcast interviews with these and other producers can be found in the Precision Ag Minute archives.

Randy Reznicek
John Deere systems used: GreenStar Yield Mapping System

Yield Monitoring Q: What exactly is yield monitoring?
A: Yield monitoring is often the first step that producers take in precision farming. This device is an electronic tool that collects data on crop performance for a given year.

Q: What are some of the benefits of yield monitoring?
A: Yield monitoring helps to identify weak areas so growers are able to properly target these specific areas. After targeting deficient areas growers are then able to properly fertilize. This process helps improve weak areas while also saving money. Instead of fertilizing the entire field, yield monitoring makes it possible to single out and fertilize only the segments that are considered weak and lack a proper amount of nutrients.

Q: Can you use yield monitoring by itself?
A: Yes. However, it seems to work better with other avenues such as grid and soil sampling. With grid sampling we find that different areas need different amounts of fertilizer.

Q: How has yield monitoring benefited growers?
A: Growers gain knowledge and insight from devices such as yield monitoring and grid sampling. This allows them to better manage their farms while also making better management decisions. When weak areas are identified and addressed, growers see positive environmental benefits while also seeing economic gain.

Q: Do growers save a significant amount of money while using this technique?
A: Through yield monitoring and the maps they provide, growers are able to identify the most underperforming areas. Growers can then sample the soil of these specific areas while not having to do the rest of the farm. This allows growers the ability to cut back on products. Not every part of a farm needs the same amount of fertilizer, and yield monitoring, with the help of soil and grid sampling, helps producers be selective in what parts of their farms need special treatment.

Precision in Practice

Another “Reach for the Stars” Winner in Illinois

Cindy Zimmerman

Brownfield NetworkDave RussellThere were a total of 15 growers nationwide who won the American Soybean Association/John Deere Reach for the Stars contest this year, and two of them were from Illinois.

Dave Russell of Brownfield Network recently caught up with Chris Von Holten of Walnut, Illinois to ask how he is enjoying the use of a John Deere precision technology package for one year free. Chris was already familiar with precision ag, but he has found new benefits with this system.

Listen here to Dave’s interview with Chris here: Listen to MP3 Chris Von Holten (2 min mp3)

Check out all of the interviews with Reach for the Stars winners in our audio archive section and check back regularly for updates throughout the growing season.

Audio, Equipment, Farm Broadcast Reports, General, Reach for the Stars

John Deere OptiGro helps manage N levels

Melissa Sandfort

Soil and weather conditions this spring in Iowa and surrounding states could have a major impact on development of the region’s corn crop going into the heart of the growing season, says an area agronomist. Crop stress associated with nitrogen deficiency should be a big concern for corn growers who experienced a cool, wet spring. That stress may start showing up soon in some fields.

According to Tracy Blackmer, an agronomist with the Iowa Soybean Association, the large amounts of rain and extended wet growing conditions this spring in some parts of Iowa and neighboring states resulted in higher than normal leaching and denitrification of earlier applied nitrogen fertilizers. In addition to wet weather, Blackmer adds that numerous other field and soil conditions, including crop residue levels, soil pH and type of nitrogen fertilizer used, can impact nitrogen availability and cause deficiency stress.

OptiGro.jpg “Nitrogen stress is critical to plant development from the eighth leaf stage to silking when the plant’s need for nitrogen is at its peak,” says Blackmer. He notes that similar wet weather in the spring of 2004 resulted in nearly 75 percent of tested fields in some areas of the state being nitrogen deficient during the growing season. This year could follow that same pattern.

Blackmer says remote sensing using aerial photography can be an effective tool to help detect nitrogen deficiency in plants early so that additional nutrients can be applied in a timely fashion.

Crop images provided by remote sensing services, such as the OptiGro™ system from John Deere Agri Services, make it even easier to detect even subtle changes in chlorophyll levels within the crop canopy, which correlate directly to nitrogen availability to the plants. “Remote sensing can be effective in detecting problems early, before it results in significant yield losses,” Blackmer adds.


3 colors or less

Melissa Sandfort

As mentioned in a previous post, as we get deeper into the “precision revolution,” compatibility is growing, and practitioners are choosing their brands of equipment more carefully. That seems to be supported by the results of a recent reader poll, showing that nearly 60% run their operations with 3 brands or less of equipment.


Q: Counting self-propelled equipment, electronic controllers, GPS receivers, in-cab computers, yield monitors, and implements, how many different brands of these types of equipment do you use in your operation?

1-3 brands: 57%
4-6 brands: 33%
7-9 brands: 2%
10 or more brands: 8%
Total Responses: 46

Content courtesy of Paul Schrimpf, PrecisionAg, a Meister publication.


New Self-Propelled Sprayers

Cindy Zimmerman

SprayersJohn Deere has just introduced a completely new line of sprayers – the 4730, 4830 and 4930 Series Self–Propelled Sprayers.

According to Deere, this new line–up sets new standards for sprayer performance, versatility and productivity.

“We’ve put together a complete family of self–propelled sprayers to meet the productivity demands of all markets, from growers to commercial applicators,” says Craig Weynand, product marketing manager, John Deere Des Moines Works.. “And all the sprayers are loaded with integrated performance–enhancing technology which includes precision guidance, mapping and variable rate software. These machines truly are the most efficient sprayers ever built by John Deere.”

The 4830 also features the standard GreenStar 2™ monitor pre–loaded with precision guidance, mapping, and variable rate software. The optional Boom Trac Pro automatic boom leveling maintains a consistent height over the crop while Swath Control Pro automatically turns nozzle sections on and off at end rows, waterways and other non–spray areas. This intelligent technology is designed to help operators cover more acres in less time, spray product more efficiently and reduce operator fatigue with the assisted–steering system of optional AutoTrac™.

Read more about these new sprayers on John Deere’s website.

Equipment, General, Media Room

Nebraska “Reach for the Stars” Winner

Cindy Zimmerman

KFRMToewsDuane Toews of KFRM, the “Voice of the Plains” in Clay Center, Kansas has been keeping in touch with Todd Swanson of Wahoo, Nebraska who was one of the John Deere/American Soybean Association Reach for the Stars contest winners.

Duane sent in two reports with Todd about how the precision ag technology package he is getting to try out for a year free of charge is helping him so far this season.

Listen to MP3 Duane and Todd 1 (2:30 min mp3)

Listen to MP3 Duane and Todd 2 (2:30 min mp3)

Audio, Equipment, Farm Broadcast Reports, General, Reach for the Stars

Illinois “Reach for the Stars” Winner

Cindy Zimmerman

Brownfield NetworkDave RussellBrownfield Network had a couple of “Reach for the Stars” winners in their coverage area, which includes Missouri, Illinois, Indiana, Nebraska, Iowa, and Wisconsin.

In this interview, Brownfield reporter Dave Russell interviews Ted Vinson of Fithian, Illinois who was one of the lucky winners in the promotion by John Deere and the American Soybean Association that allows him to use John Deere’s precision ag technology for a year free.

Listen here to Dave’s interview with Ted here: Listen to MP3 Ted Vinson (3 min mp3)

Stay tuned to for more interviews throughout the 2007 growing season with the Reach for the Stars winners.

Audio, Equipment, Farm Broadcast Reports, General, Reach for the Stars