For farmers in the Mid West, August is one of the most valuable months to walk your corn.
By now, your crop has largely revealed how it responded to weather, fertility and management throughout the season. While there’s little left to influence yield directly, there’s still plenty to learn. The observations you make now can help you reduce harvest losses, evaluate this year’s program and make more profitable decisions next season.
Here’s where to start.
Before you look anywhere else, pull a few ears from different parts of your field. They tell you more about this season than almost anything else.
What should you be seeing and why does it matter?
Look for ears with consistent kernel depth and good tip fill. Uniform ears are a sign your crop had enough energy, water, and nutrients to finish grain fill. Blank tips or shallow kernels often point to stress that reduced yield and ultimately your profitability.
What should you do?
If you’re seeing poor tip fill across the field, ask what was different. Take notes while the season is still fresh. Those observations will help you make better management decisions next year. Some of the questions to answer are:
Your crop is still working for you. As long as the leaves stay green, they continue producing the energy needed to fill kernels and maximize yield.
What should you be seeing and why does it matter?
The upper canopy should still be green and healthy during grain fill. If plants are shutting down early, they are running out of resources and pulling nutrients from leaves, and sometimes stalks, to finish the ear. That usually results in lighter kernels, lower test weight, and reduced yield.
What should you do?
Walk the field and look for patterns. If the problem is widespread, think back to earlier in the season. Moisture stress, nutrient shortages, disease pressure, or poor root development often become visible now. While you can’t reverse early senescence, identifying the cause helps you improve next year’s program.
The crop above ground only tells half the story. Digging a few plants gives you a much better understanding of how your crop handled the season.
What should you be seeing and why does it matter?
Healthy roots should be firm, well developed, and free from obvious signs of rot. Strong root systems continue supplying water and nutrients during grain fill, helping the crop perform through periods of stress. Weak or damaged roots often explain why one field finished strong while another struggled.
What should you do?
If roots are shallow or unhealthy, think back to planting conditions. Compaction, saturated soils, restricted root growth, and early-season stress often show up at the end of the season. Record which fields struggled so you can address those issues before next spring.
Weak stalks don’t just make harvest more difficult. They can cost you yield, time, and money.
What should you be seeing and why does it matter?
Push a few plants about 30 degrees from vertical. Healthy stalks should spring back. Weak stalks are much more likely to lodge, increasing harvest losses and slowing harvest operations.
What should you do?
If plants fail the push test, move those fields higher on your harvest schedule. Harvesting weaker fields first can help reduce lodging losses, improve harvest efficiency, and protect grain quality.
This is where the real learning happens. Don’t wait for the yield monitor to tell you the whole story.
What should you be seeing and why does it matter?
Compare fields, hybrids, or treated and untreated areas. Look for differences in ear fill, canopy health, stalk strength, and overall uniformity. The differences you see today often explain the yield differences you’ll measure at harvest.
What should you do?
Take photos. Record observations. Mark locations. Once harvest is complete, compare your field notes with your yield maps. Combining what you saw in August with your harvest data is one of the best ways to identify which management decisions delivered the strongest return on investment.
The most valuable asset on your farm isn’t just your yield. It’s your data. Every field walk, every observation, and every harvest result helps you make more informed decisions that protect profitability season after season.
Healthy corn should have a green upper canopy, well-filled ears, firm stalks, and strong roots. The crop should still be actively filling kernels.
Yes. Heat, drought, disease, or nutrient stress during grain fill can reduce kernel weight and final yield, even after successful pollination.
Pull ears from different parts of the field. Look for consistent kernel depth and good tip fill. Blank tips or shallow kernels often indicate the crop experienced stress during grain fill.
Some lower leaf yellowing is normal. If the upper canopy is yellowing early, it may indicate moisture stress, nutrient deficiency, disease, or reduced root function.
Use the push test. Push plants about 30 degrees from vertical. Healthy stalks should spring back. Plants that remain bent or break may be at greater risk of lodging.
Yes. Digging plants helps you evaluate root health, identify compaction or disease, and understand how well the crop supported grain fill.
Prioritize those fields for earlier harvest. Harvesting before lodging occurs can reduce field losses and protect grain quality.
Field walks help you identify what’s working, spot potential harvest risks, and collect observations that improve next year’s management decisions. Yield maps tell you what happened. Walking your fields helps explain why.
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