Crop Express – October 2026: Herbicide Weed Control, Midwest Yields and Corn Diseases
This October edition of Crop Express covers six updates from the field: herbicide weed control research, Midwest soybean and corn yields, western Corn Belt diseases, Carbon Cycle trials, Brazilian AGNYTE research, and a new member of our team. We also have details on our 2027 Research Tour.
Jump to any section below.
Herbicide Weed Control: Florida and Purdue University Herbicide Extender Study
Herbicide weed control is the focus of research presented this month from the University of Florida and Purdue University. The studies examine herbicide performance over time and differences in weed control with Satchur 8 and other treatments.
Why Residual Herbicide Weed Control Can Decline
Preemergence herbicides help control weeds before they become established. But residual weed control depends on more than the product applied. Soil moisture, texture, organic matter, application timing, and weather can all influence how well herbicides perform.
According to University of Minnesota Extension, many preemergence herbicides need approximately 0.5–1 inch of rainfall or irrigation within about 10 days of application to activate in the soil. Insufficient moisture can delay activation, while excessive rainfall can move some herbicides below the weed-germination zone.
Soil characteristics matter too. Herbicides can bind more strongly in heavier soils or those with high organic matter. In sandy soils, some herbicides move more freely, potentially reducing their concentration where germinating weeds are located.
Thinking About Making Fall Herbicides Last Longer?
Dr. Ramdas Kanissery of the University of Florida conducted replicated research at the Southwest Florida Research and Education Center evaluating the addition of Satchur 8 to preemergence herbicides.
The treatments were applied to sandy soils, using the same herbicide rates with and without Satchur 8 at 0.1% v/v.
The trial data show differences in weed control over time, particularly at the later evaluation dates.
University of Florida Trial — Pendimethalin Treatment
Evaluation date | Without Satchur 8 | With 0.1% Satchur 8 |
April 29 | 99.2% | 99.4% |
May 7 | 97.8% | 98.9% |
May 15 | 90.3% | 96.6% |
May 22 | 85.8% | 93.4% |
May 30 | 80.0% | 92.0% |
June 5 | 69.3% | 83.0% |
June 13 | 53.8% | 75.8% |
June 21 | 41.3% | 69.3% |
June 27 | 34.5% | 67.3% |
July 10 | 18.8% | 55.5% |
July 17 | 8.8% | 48.0% |
July 29 | 4.5% | 38.5% |
August 12 | 1.0% | 29.0% |
University of Florida Trial — Flumioxazin Treatment
Evaluation date | Without Satchur 8 | With 0.1% Satchur 8 |
April 29 | 99.7% | 100.0% |
May 7 | 99.6% | 100.0% |
May 15 | 99.2% | 99.8% |
May 22 | 98.1% | 99.8% |
May 30 | 96.0% | 99.7% |
June 5 | 93.2% | 99.6% |
June 13 | 89.2% | 99.4% |
June 21 | 84.8% | 98.8% |
June 27 | 84.1% | 98.3% |
July 10 | 80.3% | 96.9% |
July 17 | 68.3% | 96.6% |
July 29 | 63.0% | 95.0% |
August 12 | 58.0% | 83.8% |
By August 12, the pendimethalin treatment had 1% observed weed control without Satchur 8, compared with 29% with Satchur 8. In the flumioxazin treatment, the corresponding figures were 58% and 83.8%.
These results suggest improved persistence of weed control in the conditions of this particular replicated trial. They should not be assumed to predict performance under all soil and weather conditions.
Purdue University Herbicide Extender Study
The Purdue University study included weed-control comparisons across several herbicide treatments and weed species.
The research charts cover four herbicide programs and measure percentage control of weeds including barnyardgrass, velvetleaf, lambsquarters, amaranth, crabgrass, and ragweed.
The charts allow us to compare Satchur 8 with other treatments across different weed species rather than relying on one overall weed-control figure.
Planning Herbicide Weed Control for the Next Season
University of Minnesota Extension recommends beginning with effective preemergence weed control, selecting herbicides appropriate for the weed species present, and considering multiple effective sites of action to help manage herbicide resistance.
Fields with weeds that emerge over an extended period, such as waterhemp, can require particular attention to residual activity and follow-up scouting.
These considerations make it useful to evaluate not only initial weed control but also how treatment performance changes through the season. Always follow the applicable herbicide labels, including crop restrictions, rates, tank-mix compatibility, and application timing.
Sources:
Overview of Yields from the Midwest
The Bean Yields Across the Region Are Above Average
Across the Midwest, growers are reporting higher soybean yields than expected considering the early-season frosts, a wet start, and a dry midseason.
The low disease pressure in fungicide-treated fields, coupled with wider use of biostimulants and biologicals, led to higher performance in the field and in our trials.
Big Bean Plots — Imperial, Nebraska
The Imperial, Nebraska plots included Big Bean treatments, with reported yields of 112.07 bu for YieldEdgeFX followed by Big Bean, 110.54 bu for Ultra Fluent Followed by Big Bean, X19 followed by Big Bean — 114.28 bu
Corn Yields Are Disappointing Across Our Trade Area
Corn yields have been disappointing across our trade area.
Three major challenges affected yield potential:
Frost damage early in the season reduced yield potential in the western region.
Heat stress and dry weather during pollination affected corn development.
Nutrient losses due to heavy rains reduced nutrient availability.
Western Corn Belt Diseases
Corn fields across the western region are showing northern corn leaf blight, bacterial leaf streak, and nitrogen deficiency.
Northern Corn Leaf Blight
Bacterial Leaf Streak
Nitrogen Deficiency and Northern Corn Leaf Blight
Carbon Cycle Trials
Precision Soil Management — Carbon Cycle Trials
Precision Soil Management conducted Carbon Cycle trials examining soybean yields following a fall application of Carbon Cycle.
Soybean Yields Following a Fall Carbon Cycle Application
The yield maps below show soybean yields following a fall Carbon Cycle application. The Carbon Cycle treatment areas are identified on each map.
Brazilian AGNYTE Study
AGNYTE Maize Trials — Brazil 2026
The Brazilian AGNYTE study evaluated corn yield, plant growth, nitrogen uptake, and different rates of top-dress urea.
Trials were conducted at four sites:
Londrina, Paraná
Piracicaba, São Paulo
Uberlândia, Minas Gerais
Vicentinópolis, Goiás
The study included eight treatments with four replicates. The corn was sown in March 2026, and AGNYTE was applied once at V4–V8 at either 50 or 100 g/ha.
The top-dress urea comparisons included a half rate of 217 kg/ha and a full rate of 434 kg/ha.
Half Rate of Top-Dress Urea Plus AGNYTE Compared with Full-Rate Urea
The trials showed that half-rate top-dress urea plus AGNYTE at 100 g/ha produced numerically equal or higher corn yields than full-rate urea alone at all four locations.
Corn Grain Yield (t/ha, 13% moisture)
Trial location | Half-rate urea alone | Full-rate urea alone | Half-rate urea + AGNYTE 100 g/ha |
Londrina | 5.34 | 5.94 | 7.15 |
Piracicaba | 5.01 | 5.90 | 6.15 |
Uberlândia | 5.04 | 5.88 | 5.98 |
Vicentinópolis | 5.18 | 6.08 | 6.55 |
Four-site average | 5.14 | 5.95 | 6.46 |
The four-site average was 6.46 t/ha with half-rate urea plus AGNYTE at 100 g/ha, compared with 5.95 t/ha for full-rate urea alone.
The chart also includes statistical groupings for the individual locations; a numerical yield advantage should not be interpreted as a statistically significant difference at every site.
New Team Member
Welcome Taylor Moore
Taylor Moore is the newest member of the Planet Earth team.
She grew up on a farm in Indiana and graduated from Purdue University. Taylor worked in soil biology and crop insurance before joining us in September.
She and her husband, Drew, live on a farm in Attica, Indiana.
Taylor will work in Indiana, Illinois, and Michigan.
Thank you for your support of our people and products.
Save the Date: 2027 Research Tour
August 10, 2027
Join us for our 2027 Research Tour.
The tour will include five agronomic stations covering:
Crop residue management and tillage
Plant nutrition
Herbicide stress
Disease management
Weed control
Biological fungicides
A private dinner is also planned.
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