2024 On-Farm Research Report

Page 1


Eric Anderson, MSU Extension Soybean Educator

Mark Seamon, MSC Research Director

CONTENTS

On-farm Research Report Introduction

Trial Location Map

Introduction to Experimental Design, Statistical Analysis and Interpretation

Michigan Soybean Committee Research Priorities

Broadcast Potassium Fertilizer

Planting Rates

Spring Tillage

Planting Date x Maturity Group

Soybean Seed Inoculation

In-Furrow Starter Fertilizer

In-Furrow Radiate® and Accomplish Max™

ILeVO® vs. Saltro® Seed Treatment

ArchiTech Plant Growth Regulator/Foliar Fertilizer

Delaro® Complete Foliar Fungicide for High Yield

Delaro® Complete Foliar Fungicide for White Mold

White Mold Fungicide Application Timing

Slug Damage in Soybeans

Grower Input for 2025

THANK YOU to the farmer cooperators for contributing their land, equipment and time during the season to help improve Michigan soybean production.

For more information on participating in the 2025 Michigan Soybean On-farm Research Program, contact Eric Anderson at (269) 359-0565 or eander32@msu.edu.

This year marks the 14th season of the soybean on-farm research program, made possible by the checkoff investment of Michigan soybean producers. This year, 49 producers around the state conducted on-farm research trials within 12 projects. Contained in this publication you’ll find the results from 60 individual trial locations. The research projects were developed with producer input and represent some of the most challenging production issues confronting producers. Most of the projects were conducted at multiple locations and, in some cases, across several years, improving the reliability of the results presented in this research report.

Agronomic and economic data are presented for each treatment. Break-even yields utilized the projected USDA 2024-2025 average soybean price of $10.80 per bushel, the manufacturers’ suggested retail prices for all products, and application costs associated with the treatments.

Conducting these trials would not be possible without the strong partnership between the Michigan Soybean Committee (MSC) and Michigan State University Extension (MSUE). A few examples of the benefits of this unique collaboration include funding for:

• MSUE state-wide soybean educator and on-farm research program coordinator Eric Anderson who took the reins from Mike Staton this past spring upon his retirement

• MSUE field crops educator Teresa Crook (based in the Saginaw Bay region) who devotes half of her time to soybean research and programming and was instrumental in creating this year’s report

• Six MSUE staff (Jenna Falor, Monica Jean, Phil Kaatz, Steve Whittington, Madelyn Celovsky and Nicolle Ritchie) who were instrumental in lining up and working with on-farm cooperators

• A summer intern, David Apple, who collected and organized soil and tissue samples and took stand counts for several trials

We also want to thank MSUE educator Rich Price and members of the Basso lab for assistance with yield monitor file analysis and Jill Check, graduate student in Dr. Marty Chilvers’ lab, for help with statistical analysis.

2024 On-Farm Trial Locations

Why Does Research Need to be so Complicated?

Replications, Randomizations, Statistics, ugh!

Many well-intentioned people and businesses are looking to sell products and services to farmers with claims of improving profitability for the farmer. As potential buyers, farmers need to know how to minimize risks and only invest in those things that, on average, will make them money or improve their farm over the long term. Research can help minimize risk by learning what works and what does not before getting to field-scale decisions. On-farm research by an unbiased source can evaluate which products and practices actually make more money and distinguish real differences from the white noise of field and weather variability, fertility difference, etc. Scientific methods typically used by researchers to minimize and isolate variability include randomization, replication, minimizing variables and making accurate measurements. Often, accurately measuring a mere one to two bushel difference is the key.

The on-farm research trials coordinated by MSC and MSUE include the use of multiple replications (typically four to six) within a field as well as randomization of trials with more than two treatments (Figure 1). These practices allow for the use of statistics to determine if the differences measured were caused by the treatment or were the effect of other variability (pest damage, water damage, soil pH, etc.) The statistical analysis will provide a least significant difference (LSD). When the crop yield or stand have differences greater than the LSD, the difference is caused by the treatment in at least 90 percent of the cases. This 90 percent is known as the confidence level and can be adjusted in the analysis. As a comparison, many university analyses use the 95 percent confidence level. If you are comfortable with a higher level of risk, you may consider using a lower confidence level.

As you have witnessed, crop yields can vary greatly from one combine pass to the next without changing any management. Since this variability will always be part of production, we strive to learn despite their complicating simple comparisons. The extra effort it takes to replicate treatments across a field many times, collect data on individual strips and analyze the many data points is worth the effort to help everyone be confident in the repeatability of the effect of the practice or product.

A special thanks goes out to all the farmer cooperators who make the extra effort to learn and agree to share the results with their peers across the state through their participation in our on-farm research program. Figure 1. Aerial view of trial field

MICHIGAN SOYBEAN COMMITTEE

FY24 FUNDED RESEARCH CATEGORIES

In FY24, the Michigan Soybean Committee funded nearly $700,000 in soybean production research using soybean checkoff dollars. Funding is divided among the categories listed below to provide well-rounded research that is relevant to Michigan soybean farmers.

Broadcast Potassium Fertilizer Trial

Purpose: Muriate of potash (a.k.a. Potassium chloride, or potash, 0-0-60) has a high salt content compared with other forms of potash such as sulfate of potash (SOP, 0-0-50-18S). Potash has a salt index of 116 while SOP has an index value of 43. However, SOP typically costs 40–50 percent more per pound of K2O than potash. Some farmers believe the high salt index of potash affects soybean’s ability to achieve its yield potential. The purpose of this trial was to determine whether soybean yield and net income are affected by potassium fertilizer source.

Procedure: This trial compared the same maintenance/crop removal rate of potash vs. SOP broadcast prior to planting. Crop removal rate was based on the cooperator’s proven yield goal. Broadcast strips alternated across the field with four replications.

Results: Potash application and planting information are found in Table 1 and soil test levels in Table 2. No significant difference in yield was found between the two potassium sources (Table 3), and tissue nutrient analyses (Table 4) did not reveal any differences between the two treatments. Given the higher cost of SOP, the net income was $22 per acre lower with SOP compared to potash. The lack of difference in yield may be attributed to the fact that the Allegan location received nearly 1.0 inch of rainfall between potash application and planting, which may have allowed the chloride salts to leach out from the initial rooting zone.

If you are planning to use SOP in spring 2025, please consider participating in this trial.

Table 1. Background information for the potassium source trial

* CP - chisel plow, HSD - high-speed disc

** Rainfall data obtained from nearest MSU Enviroweather station

2. Soil test report for the potassium source trial

Bold values shaded in yellow were low or very low

Table 3. The effect of potassium source on soybean yield and income in 2024

Table

Bold values shaded in yellow were low

Planting Rate Trial

Purpose: Soybean planting rates were studied in on-farm trials at 66 locations from 2015 to 2021. Those trials are summarized in Figure 1. Producers continued to express interest in this topic at winter meetings, so the study was revisited in 2024. Many acknowledged reducing seeding rates in the past based on these findings with further reductions considered if these findings were updated and reinforced. The purpose of this trial was to evaluate how reducing planting rates will affect soybean yield and income across yield environments.

Procedure: Four target planting rates (70K, 100K, 130K and 160K seeds per acre) were compared at 11 locations in 2024 with the lowest rate being 10K less than what was used in previous years. Stand counts were taken at all locations, except Van Buren, to determine final plant stands at each location. Projected market prices and conservative seed costs were used to determine the income (gross income minus seed cost) resulting from the four planting rates.

Results: Yield response (Table 2), stand loss rate (Table 3), and net income (Table 2, Figure 2) in 2024 were very similar to previous years. When averaged across all 11 sites, yields in 2024 were similar at the three highest seeding rates. Yield responded to seeding rate at seven locations with the lowest rate yielding the lowest. The 160K and 130K rates yielded the highest at these seven locations with the 100K rate being statistically similar to the highest rates at three of those sites. Income was maximized at the 130K seeding rate with the 100K rate producing just $3 per acre less.

Given the consistency of yield and net economic return results over the eight years of this on-farm trial, farmers who have made incremental seeding rate reductions in the past may want to consider another reduction to improve their bottom line. As always, we encourage the use of strip trials to minimize risk when trying a new practice.

Figure 1. Average planting rate effects on soybean yield and income from 2015 to 2021
Table 4. Soybean tissue nutrient analysis

Planting Rate Trial, continued

Table 1. Tillage, planting equipment, row spacing, CEC, planting date, planting depth and seed treatment in 2021

* CP - chisel plow, D - disc, FC - field cultivator, SF - soil finisher, NT - no-till, VT - vertical tillage

Table 2. Effect of four planting rates on soybean yield and income in 2024

Seed cost: $70 per 140,000 seed unit

Table 3. Target planting rates, actual plant stands and average stand loss in 2024

Stand counts from the Van Buren location were not included.

Figure 2. Effect of four planting rates on soybean yield in 2024

Typical plant from the lowest two planting rates

Spring Tillage Trial

Purpose: The purpose of this trial was to evaluate how a single pass of any tillage implement selected by the trial cooperators affected soybean yield and income in 2019, 2020, 2021 and 2024.

Procedure: A single tillage pass was compared with a non-tilled control at two locations in 2019, three in 2020, two in 2021 and one in 2024. A two-pass system was compared with a non-tilled control at one location in 2020 and 2024. All tillage operations were performed in the spring except for the two-pass system in 2024, and the tillage tools used at each site are listed in Table 1. Stand counts were taken to determine if the tillage operations affected emerged populations.

Results: Tillage increased soybean yield at two of the ten locations (Table 2). Both sites were operated by the same producer. In 2020, he gained 3.5 bushels per acre and increased income by $17.00 per acre. In 2021, he increased yield by 2.8 bushels per acre and income by $34 per acre. When all ten sites were combined and analyzed, tillage increased yield by 1.4 bushels per acre and increased income by $1.00 per acre (assuming a single tillage pass). These results are consistent with other research findings from the northern U.S., Canada and Michigan. Soybean yield increases as a result of tillage are not consistent and typically do not outweigh the lower costs and the conservation benefits of no-till practices.

Tillage produced mixed results on final plant stands. At the Barry-20 site, the two tillage operations increased stands by 16,700 plants per acre. At Isabella-20, a single pass of a disk reduced the final stand by 3,500 plants per acre. Stand counts at all other sites were not statistically different between tilled and the no-till control strips.

Despite the lack of consistent economic returns to tillage, many producers feel tilling the soil prior to planting soybeans offers other benefits including: improved marestail control; improved planter/drill performance to achieve desired stand; burying residue to alleviate slug problems; and the ability to dry out the soil surface allowing earlier planting under wet soil conditions.

Table 1. Background information for the tillage trials conducted in 2019–2021 and 2024

Table 2. The effect of tillage on soybean yield and income in 2019–2021 and 2024

** Two tillage passes used

Cost of one tillage pass: $14.00 per acre

Figure 1. Yield difference produced by one or two tillage passes from 2019–2021 and 2024

*Yield difference was statistically significant

** Two tillage passes used

Table 3. Effect of a single spring tillage pass on soybean plant stand in 2019-2021 and 2024

Planting Dates vs. Maturity Groups Trial

Purpose: Early planting was studied at 25 sites over five years in on-farm trials from 2019 to 2023. Although results were not uniformly positive, on average yield was increased by 1.5 bu/ac when planted approximately two to three weeks earlier than normal. These results agreed with numerous university planting date trials across the country. Conventional wisdom says to choose a longer maturity group (MG) variety to maximize growth potential and yield when planting early. However, research from University of Wisconsin showed a relatively wide range of maturity groups produced similar yields when planted early. The purpose of this trial was to determine whether earlier MG varieties produce higher yields when planted early.

Clear distinction between planting dates and maturity groups Photo taken September 3, 2024

Procedure: This trial had two variables: 1) Planting date—in or near the third week of April compared with 3–4 weeks later; and 2) Maturity group—two varieties nearly one full MG apart, all other traits as similar as possible. All other management practices were similar to isolate the effects of these two variables. Field-length plots were fully randomized and replicated four times at two locations in 2024. Two MGs were planted with only one planting date in Shiawassee.

Results: Planting background information is presented in Table 1 and soil test data in Table 2. Early planting produced higher yields than later planting regardless of MG (Table 3, Figure 1). Early-planted soybeans yielded 11.3 bu/ac higher than later-planted soybeans when averaged across maturity groups for Kalamazoo and Branch combined. No differences were detected between MGs at the later planting at either location. However, the longer MG variety yielded 2.7 bu/ac higher than the shorter MG at the earlier planting in Kalamazoo. When averaged across all three locations, there were no statistical differences between MGs at either planting timing.

Changes in planting date and variety selection can impact stand establishment, and efforts were made to conduct stand counts to determine potential impact. However, due to unforeseen challenges, reliable stand count data were not able to be collected for this trial in 2024.

No differences in number of nodes per plant were found when averaged across locations (Table 4). Node counts were different among treatments at the Branch location but not the other locations or when averaged across locations. Soybean plants with a longer maturity group planted early had one node more than early maturity group varieties whether planted early or late. We want to thank Drs. Manni Singh and Christy Sprague for their input in designing this trial.

Table 1. Background information for the planting date by maturity group trial

Table 2. Soil test levels for organic matter, CEC, phosphorus, potassium, and pH at trial locations in 2024

Table 3. Effect of planting date and maturity group on soybean yield and income in 2024

Two maturity groups planted on a single date

Figure 1. Yield differences produced by different planting dates and maturity groups in 2024

Same letters indicate similar yield at each location

* Only one planting date at this location

Table 4. Effect of planting date and maturity group on node counts

Soybean Seed Inoculation Trial

Purpose: Legume crops like soybeans have a symbiotic relationship with N-fixing bacteria whereby the soybean plant provides sugars to feed the bacteria which then fix atmospheric N into a form the plants can use. These bacteria - Bradyrhizobium japonicum in the case of soybeans - colonize the roots to form nodules which are 1/16 to 1/4 inch in diameter.

Typically, soybean seeds do not need an inoculant added if soybeans have been grown in the field in the past 3–5 years, as the bacteria will survive in the soil. However, under certain conditions such as soil pH below 6.0, soils with high sand content, or past flooding events lasting more than a week, it may be beneficial to introduce B. japonicum via seed treatment or in-furrow. Many farmers routinely inoculate their soybeans without knowing whether they will receive a return on their investment.

Procedure: This trial had two treatments: soybean seed without an inoculant, and seed from the same lot with an inoculant of the farmer’s choice. The trial was conducted by placing the inoculated seed in half the planter and the non-inoculated seed in the other half. There were at least four replications at each of the four locations in 2024.

Results: When averaged across locations, yield was not affected by the inoculant. Inoculated plots produced higher yields than the non-inoculated plots at one of the four locations, resulting in a net return to inoculation of $0.56 per acre.

If you will grow soybeans in 2025 in fields where they have been grown recently, consider hosting a trial to see whether inoculating seed will be beneficial to your operation.

Table 1. Key background information for the inoculant trials

Table 2. The effect of seed inoculant on soybean yield and income in 2024

Different letters indicate statistically different yields

* Yield difference was statistically significant at this location

Figure 1. Yield difference produced by soybean inoculation in 2024

In-Furrow Starter Fertilizer Trial

Purpose: Producers consistently rank nutrient management as a high priority for on-farm research and reference starter fertilizer specifically. They want to know if applying nutrients in-furrow at planting is profitable. They also want to identify the most profitable nutrients and application rates. The purpose of this trial was to evaluate how various products applied in-furrow affected soybean yield and income in 2023 and 2024.

Procedure: Two treatments (in-furrow product vs. an untreated control) were compared at three locations in 2023 and eight locations in 2024. This project is different compared to other on-farm research trials in that the cooperators selected their products and application rates to evaluate on their farms (Table 1). We collected baseline soil samples from each site and nutrient levels are reported in Table 2. Stand counts were also taken, as soybean seed is sensitive to salt injury and stands could be adversely affected by such products touching the seed.

Results: Yield was increased with an in-furrow fertilizer compared with the control at one of the 11 locations and was decreased at one location (Table 3, Figure 1). Yields at all other locations were not significantly different between fertilizer and control treatments. Net income ranged from an increase of $12.45 per acre to a loss of $111.68 per acre when yield differences and cost of fertilizer product were taken into account (Table 3). Plant stands were higher with the in-furrow products compared with the control at two of the locations, lower at three locations, and not different at all other locations (Table 4).

Best practice is to fertilize according to needs identified on a recent soil test. When planting into cold soils, providing small amounts of nutrients may be beneficial until temperatures are warm enough for mineralization. Care must be taken to ensure the salt load in the fertilizer will not injure the seed when applying in-furrow.

We want to thank Herbruck’s for providing the heat-treated poultry fertilizer crumbles applied at the Jackson location and SureCrop for donating product for three locations in 2024.

Table 1. Background information for the in-furrow trials conducted in 2023 and 2024

CP = chisel plow, NT = no-till, FC = field cultivator, DR = disc ripper

*Heat-treated poultry fertilizer crumbles were applied at this location

Table 2. Soil test levels at the in-furrow trial locations

Table 3. Effect of various in-furrow products on yield and income in 2023 and 2024

Bold figures indicate low or very low soil test levels.

Figure 1. Yield difference produced by various in-furrow products in 2023 and 2024

* Yield difference was statistically significant

Table 4. Effect of various in-furrow products on final plant stands in 2023 and 2024

In-Furrow Plant Growth Products Trial

Purpose: Sometimes looking to those who have successfully grown high-yielding soybeans can give ideas for how to achieve higher yields on your own farm. According to one Michigan soybean yield contest winner, applying Radiate® and Accomplish Max™ helped him achieve those record-setting yields. Radiate contains indole butyric acid (IBA), a plant growth regulator in the auxin group that increases root formation and benefits plants under stressful conditions. Applied in-furrow, the early-season root growth could increase water use efficiency and yield. Accomplish Max reportedly feeds microbes to improve the conversion of organic and inorganic fertilizers into plant-available forms, increase nutrient availability and may improve plant tolerance to abiotic stresses. The purpose of this trial was to evaluate the effect of these combined products on soybean yield and income when applied in-furrow.

Procedure: Two treatments (in-furrow products vs. a non-treated control) were compared at four locations in 2024. Background information regarding planting is presented in Table 1. Radiate was applied at 4 oz/ac combined with Accomplish Max at 32 oz/ac. Soil moisture data was collected from nearby MSU Enviroweather stations to determine whether moisture stress may have impacted soybean growth (Figure 1).

Results: Yields were not different between the in-furrow plant growth products and the non-treated control (Table 2). When averaged across locations, a difference of only 0.2 bu/ac was found resulting in a net loss of income of $19 per acre. Yields at all locations fell short of the breakeven yield for the trial (Figure 1).

We want to thank Loveland Products, Inc. for donating product for all locations.

Table 1. Background information for the in-furrow plant growth products trials conducted in 2024

* VT - vertical till, NT - no-till

Table 2. Effect of in-furrow application of plant growth products on yield and income in 2024

Cost of Radiate: $10.00/ac; Accomplish Max : $11.25/ac; Total cost: $21.25/ac

Figure 1. Yield difference produced by in-furrow plant growth products in 2024.

ILeVO® vs. Saltro® Seed Treatment Trial

Purpose: Sudden Death Syndrome (SDS) is spreading in Michigan, and the most effective management tactics are variety selection and seed treatment. The purpose of this trial was to compare the relative effects two commercially available SDS seed treatments (ILeVO from BASF and Saltro from Syngenta) had on SDS foliar disease symptoms, yield and income.

Procedure: This trial had two treatments - base seed treatment with ILeVO vs the same base seed treatment with Saltro. Seed for both treatments came from the same lot. This trial was conducted by placing the ILeVO-treated seed in half the planter and the Saltro-treated seed in the other half. There were four locations each in 2022 and 2023 and two in 2024. All sites had a history of SDS. All fields were sampled to determine the soybean cyst nematode (SCN) population levels.

Results: Visible SDS symptoms were difficult to detect in any of the trials conducted in 2022 and 2023. Disease symptoms were not found at Monroe-24, but pressure was moderate at Lenawee-24. Soybean cyst nematode levels were low or non-existent at all locations except the Macomb site in 2022 and 2023 where they were moderate.

ILeVO produced 2.6 bushels per acre more than Saltro at Calhoun 22-2. However, yields produced by the two seed treatments were comparable at all other locations. When all 10 locations were combined, yield was not different between the seed treatments, and only $1 separated the net income with the two treatments. This is consistent with research results generated by Dr. Martin Chilvers, MSU Extension plant disease specialist, and his colleagues across the U.S. Both ILeVO and Saltro have been proven to protect soybean yield in fields having a history of SDS.

We want to thank BASF and Syngenta for providing the products for these trials and the seed dealers that treated the seed.

Table 1. Key background information for the ILeVO vs Saltro seed treatment trials in 2022–2024

* D - Disc, HSD - high speed disc, VT - vertical till, DR - disc ripper, R - land roller, FC - field cultivator ** Sudden death syndrome (SDS) pressure observations made throughout the plot area between near R6: None: no infected plants found, Low: few infected plants, Medium: several infected plants noticeable from a distance, High: extensive injury observed

Table 2. Effect of ILeVO and Saltro seed treatments on soybean yield and income in 2022–2024

ILeVO cost in 2023 : $13.00/140,000 seeds

Saltro cost in 2023: $14.85/140,000 seeds

Figure 1. Yield difference produced by ILeVO compared to Saltro seed treatment in 2022–2024

Above the line: ILeVO yielded higher; Below the line: Saltro yielded higher * Yield difference was statistically significant at this location

Closeup view of SDS on leaves

ArchiTech Growth Regulator/Foliar Fertilizer Trial

Purpose: ArchiTech is a liquid fertilizer and plant growth regulator combination distributed by AgXplore. It contains 10 percent nitrogen, five percent phosphorus, five percent potassium, and trace amounts of boron, copper, manganese, molybdenum and zinc. ArchiTech is promoted as improving photosynthesis, plant growth and plant development. It is also marketed as mitigating abiotic stresses. The purpose of this trial was to evaluate how adding ArchiTech to a planned post-emergence herbicide application affected soybean yield and income in 2023 and 2024.

Procedure: Two treatments were compared in this trial - post-emergence herbicide plus ArchiTech vs. the same post-emergence herbicide without ArchiTech. The trial was conducted at six locations in 2023 and eight locations in 2024. Soil samples were analyzed and the results are presented in Table 2.

Results: The foliar application of ArchiTech increased yield at one location by 1.8 bushels per acre and decreased yield by 0.8 bushels per acre at another in 2024. Yield was not significantly affected at any other location. When averaged across years and locations, yield was not impacted by the ArchiTech application. Due to the lack of a yield increase, income was reduced by $15 per acre.

We want to thank AgXplore for donating the product for these trials.

Table 1. Application dates, herbicides and herbicide application rates in 2023 and 2024

Table 2. Soil test levels for phosphorus, potassium, zinc, manganese and boron at the trial locations in 2023 and 2024

Table 3. Effect of a single application of ArchiTech on soybean yield and income in 2023 and 2024

ArchiTech cost: $12.00 per acre

* The foliar fertilizer application cost was not included because it was tank-mixed with a planned postemergence herbicide application

Figure 1. Yield difference from a foliar application of ArchiTech in 2023 and 2024

* Yield difference was statistically significant

** Application cost is not included, only the cost of the product

Delaro® Complete Foliar Fungicide High Yield Trial

Purpose: Delaro Complete is a relatively new foliar fungicide from Bayer Crop Science being promoted as having more consistent disease control and improving plant health and yield potential. The purpose of this trial was to evaluate how a foliar application of Delaro Complete applied at R3 affected soybean yield and income when used as a general foliar fungicide, not specifically applied to manage white mold, in 2023 and 2024.

Procedure: A foliar application of Delaro Complete was compared to a non-treated control at 10 locations in 2023 and 11 locations in 2024. The Delaro Complete was applied at 8 ounces per acre at the R3 growth stage (one pod 3/16” long on one of the upper most nodes on the main stem having unrolled leaves). Application dates, application characteristics and rainfall information for each site are presented in Table 1.

Results: Delaro Complete foliar application at R3 increased soybean yields at eight of the 10 individual trial locations in 2023 but only two of the 11 locations in 2024 (Table 2). Yield increases at individual trials ranged from 0.9 to 7.9 bushels per acre. When all 21 locations were combined and analyzed, the fungicide application increased soybean yields by 2.1 bushels per acre.

After accounting for product and application costs, the fungicide was profitable at six locations (Figure 1). The additional income ranged from $11 to $69 per acre at these locations. When averaged across years and locations, the fungicide application resulted in a net loss of $11 per acre using 2024 product/application costs and soybean prices.

We want to thank Bayer Crop Science for donating the product for these trials.

Table 1. Application dates, volume, pressure, ground speed, and rainfall information for the Delaro Complete trial locations

*Rainfall data obtained from the nearest MSU Enviroweather station

Table 2. The effect of a single R3 application of Delaro Complete on soybean yield and income in 2023 and 2024

Complete cost: $22.19 per acre; Application cost: $12.00 per acre

1. Yield difference from a foliar application of

Complete fungicide at R3 in 2023 and 2024

* Yield difference was statistically significant

** Break-even cost includes $22.19/ac for Delaro Complete plus $12/ac application cost

Delaro
Figure
Delaro

Delaro® Complete Foliar Fungicide White Mold Trial

Purpose: Delaro Complete is a relatively new foliar fungicide from Bayer Crop Science promoted as providing protection from white mold, having more consistent disease control, and improving plant health and yield potential. The purpose of this trial was to evaluate the effect of a foliar application of Delaro Complete on soybean yield and income in 2023 and 2024 when specifically applied to manage white mold.

Procedure: A single application of Delaro Complete was compared with a non-treated control at two locations in 2023 and four locations in 2024. All locations had a history of white mold. Delaro Complete was applied at 8 ounces per acre at the R1 growth stage (one open blossom on the main stem of 50 percent of plants). Soybean variety, white mold resistance rating and planting information are presented in Table 1. Application dates, Sporecaster app risk prediction at R1, application characteristics, rainfall information and disease pressure at R5-R6 are presented in Table 3.

Results: White mold pressure was rated as moderate to high at both locations in 2023 but was low or nonexistent at all locations in 2024. The foliar application of Delaro Complete increased soybean yields by more than 12 bushels per acre at Kalamazoo-23 and by 9 bushels per acre at Sanilac-24-1 (Table 2). However, yield was not affected by the fungicide at any other location. When all locations were averaged together, the fungicide application increased soybean yield by 4.4 bushels per acre.

After accounting for product and application costs, the fungicide application increased income by $14 per acre when averaged across locations and years.

We want to thank Bayer Crop Science for donating the product for these trials.

Table 1. Soybean variety, white mold resistance rating, planting dates, planting rates, and row spacing at trial locations in 2023 and 2024
Table 3. Effect of a single application of Delaro Complete at R1 on soybean yield and income in 2023 and 2024

Table 2. Application dates, volume, pressure, ground speed, rainfall information and disease severity ratings for the Delaro Complete white mold trial locations

* Fungicide applications typically recommended when apothecia development forecasts are higher than 40 percent; colors correspond to risk level as depicted in the Sporecaster app

**Rainfall data obtained from the nearest MSU Enviroweather station

**White mold disease pressure observations made throughout the plot area between R5 and R6: None: no infected plants found, Low: few infected plants, Medium: several infected plants noticeable from a distance, High: extensive injury observed

Figure 1. Yield difference from an R1 foliar application of Delaro Complete in 2023

* Yield difference was statistically significant

White mold

White Mold Fungicide Application Timing Trial

Purpose: Foliar fungicides can be an important tactic for reducing yield loss from white mold, especially when combined with other effective management practices such as: resistant/tolerant varieties, wide rows, reduced planting rates, tillage decisions and irrigation water management. Properly timing fungicide applications is essential for success but challenging for producers. The purpose of this trial was to determine the impact of fungicide application timing on soybean yield and income in 2023 and 2024. Another goal was to use the yield data from this trial to validate Sporecaster, a relatively new white mold apothecia prediction app for smart phones.

Procedure: This trial compared three different fungicide application timings to an untreated control at three locations previously infested with white mold. The application timings were: R1 (one open flower on the main stem of 50 percent of plants); 7 days after R1; and 14 days after R1. Propulse® fungicide was applied at 6 oz/ac for all application timings in 2023 and 8 oz/ac in 2024. Dates for the three application timings were entered into the Sporecaster app to determine the apothecia risk level for the dates and locations.

Results: White mold was not found at the Eaton location, was low at the Gratiot location and medium at Isabella in 2024. No yield differences were detected among treatments at any location in 2024.

Sanilac-23 was the only responsive site in either year. The two later application timings increased yield and income over the R1 application timing. Yields were higher compared to the untreated control by 4.3 bushels per acre for the R1 timing, 6.7 bushels for 7 days after R1, and 6.3 bushels for 14 days after R1. Income was increased by $29 per acre at the R1 timing, $60 per acre at 7 days after R1, and $55 per acre at 14 days after R1 at Sanilac-23.

When locations were combined across the two years, no statistical differences were observed among treatments although, numerically, yield and income increased with later fungicide applications.

The Sporecaster app indicated a low risk for all three fungicide application timings in Isabella, medium risk for all timings in Gratiot and high risk for all timings at Eaton in 2024. In 2023, the app recommended a fungicide application at all locations for all application timings with the highest risk predicted for the Sanilac location.

We want to thank Bayer Crop Science for providing the Propulse and Dr. Martin Chilvers, MSU Extension plant pathologist, for his input regarding the three application timings evaluated in this project.

Soybean flower
Table 1. Planting dates, planting rates, row spacing, and fungicide application dates at the trial locations

Table 2. White mold foliar fungicide application timing effect on soybean yield and income in 2023 and 2024

Propulse fungicide cost for a single application: $15.70 per acre; Application cost: $12.00 per acre

Figure 1. Yield difference produced by a single fungicide application at three different timings when compared to the untreated control in 2023 and 2024

* Yield difference between fungicide application timing and the control was statistically significant Bold type indicates yield differences between the later application dates and the R1 application date were statistically significant

Table 3. Sporecaster white mold apothecia development forecasts and observed disease severity at each trial location

*Fungicide applications typically recommended when apothecia development forecasts are higher than 40%, colors correspond to risk level as depicted in the Sporecaster app

**White mold disease pressure observations made throughout the plot area between R5 and R6: None: no infected plants found, Low: few infected plants, Medium: several infected plants noticeable from a distance, High: extensive injury observed

Slugs Control Is Tough, but Some Management Options May Help

Many farmers in Michigan have adopted practices such as no-till and planting cover crops to improve soil health and protect the environment. Over time, these practices provide benefits like improved soil structure, better weed control and increased biological control. However, there can be new challenges such as slugs. In 2024, we both saw situations where entire soybean fields had to be replanted due to severe slug damage; worst cases occur where seed furrows are open and slugs have direct access to germinating seeds.

As molluscs, slugs need cool, wet, undisturbed conditions to thrive. Slugs are always present in low numbers in conventionally-farmed corn and soybean fields, but historically tillage limited them to specific situations (cool wet springs or heavy parts of fields). They fed on the lower leaves of slowgrowing corn or soybean, but significant injury was rare. However, as conservation practices were adopted, slug numbers have built over time and across more acres. No-till fields with heavy residue from previous years provide ideal slug habitat, as do cover-cropped acres with dense live or dead vegetation in the spring. Note that insecticides (including seed treatments) have no effect on slugs, because they are not insects. But insecticides do kill beetles which are slug predators.

Practices that may reduce slug damage to an emerging crop:

• Avoid planting sluggy fields too early or under wet conditions where furrows don’t close. Open furrows give slugs a dark cool hiding place and direct access to seed.

• Burn-down cover crops early and set row cleaners to sweep away residue from the row

• Consider changing your seed treatment to fungicide-only to protect slug predators.

• Spread slug bait pellets if other management fails.

There are two slug baits registered in the U.S. for corn and soybean.

* Iron phosphate (for example, ‘Sluggo’) has a broad label for use on many crops, including corn and soybean in Michigan. In June 2024, MSUE educators treated replicated small areas in an infested field but found no difference in slug numbers.

* Metaldehyde (sold as Deadline) is the most common slug bait used on field crops in the region. While both corn and soybean are on the label, there is an odd state-level restriction related to soybean. This creates a confusing situation where Michigan growers can use Deadline on their corn acres but not on their soybean fields.

For more information, a good source is the OSU Extension Bulletin ENT-20 ‘Slugs on Field Crops’ found at ohioline.osu. edu/factsheet/ENT-20.

Slug damage to soybean, June 2024, near Frankenmuth. High residue and open furrows in this no-till cover-cropped field resulted in high slug numbers and complete stand loss across most of the field (left). The stand emerged as expected in a small area lacking crop residue (right). The farmer replanted twice.

Gray garden slugs on residue in the same field, and closeups of destroyed seedlings
Photos of slug damage at the Kellogg Biological Station Long-Term Agroecosystem Research site in 2024 (credit Jason Stegink)

H ave Trial Ideas? We Want to Hear From You!

Each year at our regional winter grower meetings, we share results from our on-farm research trials using the data presented in this report. We then use audience polling to gather farmer feedback on trial topic ideas for the upcoming year and gauge grower interest in hosting trials. This year, in addition to gathering feedback at our in-person events, we wanted to provide the opportunity to those of you who are unable to join us at a meeting. If you have ideas for a trial or are interested in learning more about hosting one on your farm, you are welcome to fill this form out online, or mail in this paper version.

• What is the biggest agronomic or production issue you see facing Michigan soybean growers?

• What trial topics should we look into for the 2025 growing season?

• Are you interested in learning more about hosting an on-farm trial on your farm in 2025? If yes, please include your contact information below and someone will reach out to you.

Name:

Email Address:

Address, City, State, Zip:

Phone Number:

If you complete this survey on paper, please detach this page and mail to: Michigan Soybean Committee

To complete these questions online, visit www.michigansoybean.org/host-an-onfarm-trial or scan the QR code above using your smart phone camera.

Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.
2024 On-Farm Research Report by michigansoybean - Issuu