Koenig Equipment Blog

Reading Yield Maps in Operations Center to Plan Fall Wheat Planting | Koenig Equipment

Written by Koenig Equipment | Aug 18, 2026, 7:59:59 PM

Fall wheat planting for most Ohio and Indiana growers is 3 to 4 weeks out. The seed order is either placed or nearly placed. The drill or air seeder is either serviced or on the schedule. The decision that is often still open at this point is the one that most benefits from actually looking at prior-year data: seed rate and hybrid selection across the specific field zones that are going into wheat this fall.

This is a walkthrough of how to use John Deere Operations Center Field Analyzer, cross-referenced against soil test data and as-applied planting records from the corn or soybean crop that came off those fields, to build a fall wheat prescription that reflects what your fields actually did last season rather than what an average recommendation would suggest.

If you have already gone through the July 22 Operations Center for Small Farms post and have Field Analyzer populated with your last few seasons of yield data, this is the applied use case that generates the highest return on that setup investment.

 

 

Start with the yield map that actually matters

Not all yield maps are equally useful for fall wheat prescriptions. The one you want to lead with is the yield map from the most recent complete crop on that specific field. For a field going wheat this fall, that is usually the 2025 or 2026 corn or soybean yield, depending on the rotation.

Open Field Analyzer, load the field, and look at yield spatially rather than at the field average. The average tells you almost nothing useful for a prescription. What matters is the distribution across the field — where the top 20% of the field yielded, where the bottom 20% yielded, and how those zones relate to persistent features of the field like drainage patterns, soil texture, or slope.

For most Ohio and Indiana fields, the yield distribution follows one of three patterns:

  • Consistent field, mild variance. Top-to-bottom yield spread of maybe 15 to 25 bushels per acre on corn. Zones that vary are small and scattered. These fields do well with a single fall wheat rate and rarely justify a full variable-rate prescription.
  • Clear high/low zones. Top-to-bottom spread of 40 to 80 bushels per acre on corn, and the zones are geographically coherent (a productive south end, a poorly drained north corner, a headland zone that consistently underperforms). These fields are strong candidates for a manual rate zone approach.
  • High spatial variance. Top-to-bottom spread over 100 bushels per acre, and the zones are complex and often follow topography or historical field boundaries. These fields benefit most from full variable-rate scripting and are also the fields where the ROI on precision investment is highest.

The pattern tells you the appropriate prescription approach before you write a single line of the script.

Cross-reference against the soil test

The yield map alone can mislead you. A low-yielding zone on the yield map could be low because of poor drainage, low pH, low P or K, compaction, previous field history, or any combination of the four. Each of those root causes calls for a different fall wheat response.

Pull up the most recent soil test grid results in Field Analyzer or in your agronomic software. Compare the low-yield zones from the yield map against soil test values:

  • Low yield, low pH. Fall wheat is more tolerant of low pH than corn or soybeans, but a zone that has been slowly acidifying is going to keep dropping in productivity across all crops. The right response is a variable-rate lime application before wheat goes in, then a manageable wheat seed rate. Trying to compensate with higher wheat seed rate on acidic soil does not fix the root cause.
  • Low yield, low P/K. Wheat responds well to good P and K fertility. If a zone is low on both, an increased fall fertilizer rate on that zone paired with a modestly higher seed rate is the right combination.
  • Low yield, adequate soil test values. This is the interesting case. If nutrition and pH look fine and the zone still underperformed, the cause is usually drainage, compaction, or timing (was the corn planted late on that zone, was harvest delayed, was there standing water). Wheat may or may not perform better on that zone depending on the specific issue.
  • High yield, high fertility. Do not automatically boost seed rate. High-yield zones often have adequate stand from moderate seed rates, and pushing rate higher can create lodging risk that offsets any yield gain.

The soil test cross-reference is the step most growers skip when moving from yield map to prescription. It is also the step that determines whether the prescription actually improves outcomes or just moves seed around the field.

 

 

Pull the as-applied plant date and stand count

Field Analyzer will also show you the as-applied planting data from the previous corn or soybean crop, if the planter was recording. This is the third data layer that changes prescription decisions in ways the yield map alone does not reveal.

Two things to look at specifically:

Plant date across the field. If the previous corn was planted over multiple days because of weather delays, the zones planted late almost certainly underperformed the zones planted first, regardless of any other factor. That is not a persistent zone characteristic — it is a one-time timing artifact. Do not build a prescription that overreacts to it. Fall wheat on those zones should be at the field baseline rate.

Stand count uniformity. If any zone of the previous corn crop had a stand count problem (skips, doubles, poor emergence), the yield on that zone is partly a stand issue rather than a fertility or drainage issue. Again, do not overreact — the fall wheat drill is a different machine with different failure modes, and the previous corn stand issue does not automatically transfer.

The as-applied data layer prevents the most common yield-map-only mistake: prescribing higher inputs to a zone that underperformed for a reason unrelated to the coming wheat crop.

Build the wheat prescription

Once the three layers are compared, the actual prescription decision falls into one of three approaches.

Approach 1: Single flat rate. If the field is consistent (pattern one) or the low-yield zones are explained by transient factors (late plant date, stand issues, one-time weather events), a single flat wheat seed rate is honest. Do not build a prescription just to have one. Most fields with a top-to-bottom yield spread under 25 bushels per acre are best served this way, and the extra complexity of a variable-rate script does not earn its keep.

Approach 2: Manual rate zones. If the yield map shows clear high/low zones AND the soil test explains those zones AND the as-applied data confirms it was not a timing artifact, a manual zone approach is often the right call. Split the field into 2 or 3 rate zones based on the yield map. A common structure: baseline rate on average zones, +10 to +15% on documented low-productivity zones with confirmed nutrient deficiency, -5 to -10% on documented high-productivity zones with adequate fertility. Write the zones directly in Operations Center or export to the drill controller.

Approach 3: Full variable-rate script. For fields with high spatial variance and multiple confirmed drivers, a full variable-rate script generated in Operations Center or a compatible platform (Ag Leader, Precision Planting, Climate FieldView) delivers the biggest return. The script uses the yield map as the base layer and applies rate adjustments continuously across the field based on the multi-layer analysis. This is the workflow the embedded video above walks through end to end for Operations Center specifically.

Whichever approach fits, write the prescription in Operations Center or your preferred agronomic software, export the file format the drill or seeder controller accepts, and load it before the tractor leaves the shop.

 

 

Hybrid or variety selection using the same data

Seed rate is one variable. The other is which wheat variety goes into which zone. This decision matters most on fields with clear productivity zones.

Modern soft red winter wheat varieties for Ohio and Indiana vary meaningfully in a few characteristics: winterhardiness, straw strength (lodging resistance), disease resistance packages (particularly for fusarium head blight), and yield ceiling under high-input conditions. Match variety to zone:

  • High-yield zones with adequate fertility benefit from higher-ceiling varieties that respond to nutrient availability. These varieties may have moderate lodging risk in low-population stands, so pair with a moderate seed rate on those zones.
  • Low-yield zones with fertility constraints benefit from more defensive varieties with strong disease resistance and consistent yield under stress. High-ceiling varieties are wasted on these zones because the ceiling is not reachable given the soil constraints.
  • Poorly drained zones benefit from varieties with strong winterhardiness and root disease resistance. Yield ceiling is less important than survival through a wet spring.

Most Ohio and Indiana growers plant one variety per field for operational simplicity. If your yield data suggests two very different zones within a field, splitting varieties by zone is a next-level decision that some growers implement and others reasonably choose to skip. The right call depends on operational complexity tolerance and the specific yield differential involved.

Common data gaps and how to close them

The prescription workflow above assumes you have three layers of prior-year data available. Many growers do not, and that is worth being honest about.

If you have yield data but no recent soil test: Get the soil test scheduled now. Grid or zone sampling based on the yield map layers is far more useful than a single composite sample. Turnaround from most Ohio and Indiana labs is 5 to 10 business days.

If you have soil test but no yield map: This is common for growers new to precision. The correct move for this fall is a flat rate wheat prescription based on soil test recommendations, and setting up the combine's yield monitor for the 2026 corn or soybean harvest that is about to happen. Next fall's wheat prescription becomes much stronger.

If you have neither: Fall wheat this year gets planted at the university-recommended flat rate for your region. Focus this fall on setting up Operations Center, calibrating the yield monitor for the coming harvest, and scheduling grid soil sampling for after harvest. By this time next year, you have the foundation.

 

 

Timing this month

For growers who are still finalizing fall wheat prescription decisions, the useful timeline:

  • This week: Pull yield maps in Field Analyzer, cross-reference against soil test data, identify the prescription approach that fits each field.
  • Next 2 weeks: Order any additional soil samples needed for gap fields. Write prescriptions in Operations Center. Send files to the drill controller.
  • 3 to 4 weeks out: Final drill or seeder service. Verify controller reads the prescription files correctly. Do a dry run on prescription execution.

Our precision ag team can support any part of this workflow. Common asks include help interpreting an unfamiliar yield distribution pattern, walking through prescription writing in Operations Center for the first time on a specific field, or troubleshooting a controller that will not read a prescription file. Turnaround on those calls is typically same-day during August and early September.

The Early Order Programs for MY27 planter precision upgrades historically launch in October-November, which is worth noting for growers who identify prescription capability gaps in their current planter setup during this fall's wheat prescription workflow. If you find yourself wishing your corn planter had done more of what you now want it to have done, the fall EOP window is when that gets planned.

When to call us

Two practical touchpoints for this specific workflow.

For Operations Center troubleshooting or prescription writing help, the precision ag team can walk through the workflow on a screen share within 24 to 48 hours of a request. For the fall wheat decision window this year, calls this week or next are the ones that will have material impact.

For drill or seeder pre-fall service, our service teams can typically fit a full inspection within 5 to 10 business days of a call. Later in September the shop fills up fast, so this week is a better week to book than next.

Contact Us

Schedule Service