Labor Webinars Planned for Agricultural Employers

College Park, MD – The University of Maryland and the University of Delaware will host the Hiring and Retaining Farm Employees – What you Need to Know and Do four webinars every Friday in April at noon starting on April 5th and ending on April 26.  The free webinars will cover developing an employee handbook for your operation, basic legal requirements, and how to incorporate benefits that agricultural employers deal with. The funding for this program is thanks to the Northeast Risk Management Education Center. 

The webinar schedule includes: 

  • April 5: Introduction to the Employer Guide and Workbook – Nate Bruce, Farm Business Management Specialist, UD Cooperative Extension;
  • April 12: Finding the right person, Employee Handbook, Paul Goeringer, Sr. Faculty Specialist and Extension Specialist, UMD 
  • April 19: Overview of health insurance options with case study, Jesse Ketterman, PhD, AFC, Senior Agent, University of Maryland Extension
  • April 26: Overview retirement savings options with case study, Maria Pippidis, Extension Educator, Financial Wellness, University of Delaware Cooperative Extension;

“This program will be a great opportunity for agricultural employers to get valuable information on their legal responsibilities and options,” said Paul Goeringer. “This information will be useful for any employer, regardless of the size of the operation,” said Goeringer.

For more information or to register for the webinars, go to https://bit.ly/3uwXmdx – and do not hesitate to reach out to Paul Goeringer at lgoering@umd.edu if you have any questions.

This material is based upon work supported by USDA/NIFA under Award Number 2021‐70027‐34693.

Back in a Wait-and-See Mode With Recent Dicamba Ruling

Paul Goeringer, Extension Ag Law Legal Specialist
University of Maryland

The article is not a substitute for legal advice. Reposted from the Ag Risk Management Blog

A recent Arizona federal district court ruling has vacated the 2020 registrations for dicamba products used over the top in cotton and soybean production. The ruling is based on violations of federal law requiring the public to have an opportunity to comment on the proposed “new uses” in 2020. This ruling currently means for growers that these products might not be available for the 2024 growing season. Based on the ruling, we are waiting to determine what the defendants will do next. Update: On Feb. 14, the EPA issued an existing stocks order to allow for limited continued usage for the dicambas at issue for stocks no longer in control of the pesticide companies. A table of what is allowed is below; to read that order, click here.

Court’s Decision

This litigation stems from the registrations issued in 2020 and amendments made in 2022 and 2023 by the Environmental Protection Agency (EPA) for the “new use” over-the-top applications of dicamba products. At issue in this is did EPA violate the Federal Insecticide, Fungicide, Rodenticide Act (FIFRA), the Endangered Species Act (ESA), and the Administrative Procedures Act (APA) when approving the “new use” registrations in 2020.

The court agreed with the plaintiffs that the 2020 registration was a “new use” because the 2016 and 2018 registrations had been vacated and canceled by an earlier court ruling. EPA had to treat the 2020 registration for over-the-top applications of dicamba products as a new use. This “new use” registration required the EPA to publish the 2020 registrations and allow the public to comment.

Because of the violations in issuing the 2020 registration for over-the-top use of dicamba products, the court turns to whether an exception should be granted to EPA to remand the registrations without vacatur. Vacatur is a Latin term meaning it is vacated. Based on the record, the court determines that vacatur is warranted and an exemption should not be granted. EPA had failed to consider many potential risks when assessing the new uses, and based on prior court rulings, it had effectively allowed the dicamba products on the market with no registrations since 2016.

What Does All This Mean?

We are currently back in a wait-and-see mode regarding whether dicamba will be available for over-the-top uses during the 2024 growing season. It is unclear at this time if EPA will appeal this ruling and request a stay while the Ninth Circuit is hearing the appeal. If the EPA does appeal and receive a stay, this will allow sales of dicambas used in over-the-top applications to continue. If EPA does not appeal, we could see what we did in 2020 with EPA canceling the registration based on a court ruling but allowing already purchased products to be used during the growing season.

One vital issue to note in all this is that Bayer (the parent company of Monsanto) in 2023 began to bring lawsuits claiming growers saved seeds for replanting the new Xtendimax technology. These are similar to those brought when growers would save Roundup Ready technology before the patent expired, but a few have one difference. Several lawsuits highlight that growers additionally violated patents by spraying dicambas that were unapproved for over-the-top applications. Why is it important to note this here? Many growers may assume that they can spray dicambas unregistered for over-the-top applications, but that can come with stiff penalties from state agencies and EPA and, at the same time, may open growers up to claims of patent violations.

Updated: Table from order highlighting what is allowed.

References 

Ctr. for Biological Diversity, et al. v. U.S. Envtl. Prot. Agency, No. CV-20-00555-TUC-DCB, 2024 WL 455047 (D.Ariz., Feb. 6, 2024).

Farmers May Fertilize Small Grains With Commercial Fertilizer Beginning February 15

Reposted from the Maryland Department of Agriculture

The Maryland Department of Agriculture today announced that farmers who planted small grains for harvest last fall may “top dress” these crops with commercial fertilizer in accordance with their nutrient management plans, beginning February 15, provided that crop and field conditions remain favorable.

University of Maryland researchers have determined that crop growth stages vary across the state. The Lower Eastern Shore of Maryland and Southern Maryland appear to have met the appropriate time to top-dress. However, the Maryland Department of Agriculture has given approval to all Maryland farmers to begin applying fertilizer to small grains, as long as crops have reached the “green-up” stage before applying fertilizer. The University recommends split applications of spring nitrogen with the first application occurring at “green-up” and the second application when the crops begin to joint. Check individual field conditions and avoid running heavy equipment across saturated soils.

The determination follows Maryland’s nutrient management regulations. As a reminder, manure may not be applied to fields until March 1.

For additional information on Maryland’s nutrient application requirements, contact the MDA’s Nutrient Management Program at 410-841-5959.

For a directory of University of Maryland Nutrient Management Planners, visit: https://extension.umd.edu/resource/ume-nutrient-management-advisors/.

University of Maryland Extension Peak Plan Writing and Implementation Reports Due

University of Maryland Extension Peak Plan Writing and Implementation Reports Due

The University of Maryland Extension (UME) Nutrient Management Advisors are diligently working on nutrient management plans as farmers make critical decisions for the upcoming 2024 growing season. Balancing crop needs with input costs is a major decision, making nutrient management planning an essential tool in optimizing agricultural practices. Farmers requiring a plan for the 2024 season are urged to contact their local Extension office promptly. Collecting necessary information and documents early will ensure timely plan development.

For farms February marks a busy reporting season including federal and state taxes, crop insurance, and nutrient management. Alongside financial preparations, it is important not to overlook the completion of Annual Implementation Reports (AIRs). These reports, documenting nutrient applications for the 2023 calendar year, are due by March 1, 2024. Farmers can submit their reports conveniently through mail or online via the MD OneStop Portal. Most information required for AIR completion can be found in nutrient management plans and fertilizer records. For more information on AIRs visit https://mda.maryland.gov/resource_conservation.

UME is committed to supporting farmers through February and March with regional agronomy, fruit, and vegetable production meetings. Many of these sessions offer Nutrient Management voucher credits. Interested individuals are encouraged to connect with their local UME office or refer to the Extension calendar for upcoming events: UME Events Calendar https://extension.umd.edu/news-events/events/.

UME continues to expand its team and is actively hiring advisor positions available across various counties. Interested individuals are encouraged to explore these opportunities at https://ejobs.umd.edu/postings/115994. Additionally, the UME ANMP team is excited to welcome four new advisors. The new hires are: Zoe Askew in Baltimore County, Andrea Uphold in Garrett and Allegany Counties, Rashmi Sahu in Anne Arundel County and Sabrina Summers in Frederick County. We are very happy to have them as part of the team and begin their training as UME ANMP advisors.  

University of Maryland Extension Strengthens Agricultural Expertise with Four New Nutrient Management Advisors

The University of Maryland Extension announces the addition of four Agricultural Nutrient Management Advisors to its statewide team. These hires strengthen the organization’s commitment to advancing sustainable and efficient agricultural practices across the region.

The newly appointed advisors bring a wealth of experience and expertise in the field of nutrient management, aligning with the university’s dedication to environmental stewardship and enhanced farm productivity. Dr. Darren Jarboe, Agriculture and Food Systems Program Leader at University of Maryland Extension, expressed enthusiasm about the new additions to the team stating, “We are thrilled to have such accomplished individuals join our Extension team. Their diverse backgrounds and deep knowledge in nutrient management will significantly contribute to our mission of supporting farmers and fostering sustainable agricultural practices.” 

The four new advisors include:

  • Zoe Askew, Baltimore County, is a recent graduate of Delaware Valley University, receiving her bachelor’s degree in Sustainable Agriculture and Organic Farming. She has had several years of hands-on experience working on various vegetable and livestock farms. 
  • Andrea Uphold, Garrett and Allegany Counties, is a 2013 graduate of West Virginia University where she obtained her bachelor of science degree in Animal and Nutritional Sciences as well as Agribusiness Management and Rural Development. She grew up and lives on her family’s dairy farm where she is actively involved in its daily operations. She is certified and has been writing nutrient management plans for her family’s farm and extended family and friends for ten years and recently worked as an hourly coordinator for the University of Maryland throughout the state before being hired full time.
  • Rashmi Sahu, Anne Arundel County, earned a master of science degree in Agricultural and Biological Engineering from Penn State University. She has extensive work experience in agricultural operations.
  • Sabrina Summers, Frederick County, is a Frederick County native, representing the seventh generation of farmers in her family. Her agricultural experience stems from growing up on a dairy farm, and she now assists with her brother’s crop farming operation, and has her own operation raising pastured pigs and chickens. 

The University of Maryland Extension remains committed to addressing the evolving challenges faced by farmers and the agriculture industry. The addition of these talented advisors enhances Extension’s ability to provide cutting-edge solutions and support to farmers in nutrient management planning. For more information about the program visit go.umd.edu/anmp.

Transition to Organic Production

Are you contemplating a transition to organic production, currently undergoing the transition process, or just curious about organic farming?

The University of Maryland Extension invites you to register for a half-day seminar from 8 am to 2 pm on March 19, 2024 at the Eastern Shore Higher Education Center – Chesapeake College. The agenda for the day includes presentations by Klaas Martens, Chris Johnson and Brian Kalmbach covering key topics such as the direction and future of organic production, insights into organic grain markets, and navigating certification, regulations, and requirements. Additionally, there will be a farmer roundtable discussion featuring panelists representing various aspects of organic farming, including grain, vegetable, animal, and research. Light breakfast refreshments and lunch will be served. 

Space is limited so register todayhttps://go.umd.edu/TOPP

For more information or any inquiries contact Dwayne Joseph at dwaynej@umd.edu or by calling 443-480-8369.

2023 Soybean Variety Trials

Nicole Fiorellino, Extension Agronomist | nfiorell@umd.edu
University of Maryland, College Park

Please find attached a copy of the 2023 Soybean Variety Trials results. The trial is performed annually at multiple UMD Research and Education Centers and we thank the managers at the facilities for their assistance with these trials. The factsheet can also be downloaded from the MD Crops website at https://psla.umd.edu/extension/md-crops. Many thanks to Louis Thorne, Joe Crank, and Shana Burke for their leadership and management of the trials, from seed organization, to planting, to harvest. These trials could not be completed without them.

We are grateful for the funding provided by Maryland Soybean Board to support these trials. MSB provides our program with checkoff funding to support applied agricultural research and generate results that directly benefit Maryland soybean growers.

For more information on how to interpret and utilize hybrid/variety trial data, check out our fact sheet, What do the numbers really mean? Interpreting variety trial results.

Click here to download the full report

Maryland Regional Crop Reports: November 2023

Reports are for crop conditions up to November 16, 2023.

Western Maryland

Harvest is winding down. Nearly all of the corn and full-season beans are in the bins. Some of the double-crop beans weren’t even worth the cost of the fuel to harvest them. Cover crops are looking good as is the commodity wheat and barely. There are still a few acres that will get some rye. Manure is flying as we race to beat the December 15 deadline. Hay stocks are short but FSA has had the county designated a disaster area so there is some assistance available to make up for the shortfalls. Yields are all over the place depending on when the crop was planted and when the showers arrived. As always everyone is looking forward to 2024 being a better year.—Jeff Semler, Washington Co.

Central Maryland 

No Report.

Northern Maryland

2023 harvest has been about as smooth as anyone could ask for with very few weather interruptions. All but a few acres of corn and double-crop soybeans remain. Some rains here and there have been just enough to get cover crops and small grains off to a good start, especially those fields planted early, which have put on substantial growth and tillers. Corn yields have been very strong across most of the region and even record-setting on some farms. Soybeans on the other hand are average to below average in many fields and double-crop beans range from very poor to good. All things considered, yields (especially corn) were impressive considering how dry we started and finished the season; timely rains sure do make or break yields!—Andy Kness, Harford Co.

Upper and Mid Shore

Both corn and soybean harvest is finishing up. The high yields across the region have made grain delivery the last fewPreview (opens in a new tab) weeks a little frustrating. Tanks and piles are full. Granaries have been working to move grain out, but purchasing grain with reduced hours. On a positive note, that seems to be resolved now. The weather has cooperated to make harvest as easy and stress free as possible. We are finally receiving some rain to replenish ground water. Small grains are off to a good start.—Jim Lewis, Caroline Co.

Lower Shore

Corn harvest is 95% complete. Most full season soybean has been harvested. It has been very dry in the region, and soybean moisture is below 13%. Soybeans are dusty and farmers are blowing off combines due to fire hazard. Soybean yields are coming in average to slightly above average depending on how much rain fields received. Double crop soybean following wheat is still a few weeks from being harvested. Wheat planting is underway and farmers are planting into dry fields. In many fields, cover crops are already seeing substantial growth and some farmers continue to drill winter cereal cover crops following soybean harvest.—Sarah Hirsh, Somerset Co.

Southern Maryland

Wrap-up: The last acres of soybeans and corn are making their way off fields as we wind into the last chapters of 2023 season. The season started early, with ideal planting conditions in early April. Many growers planted beans and corn during that early window. Conditions turned dry and cooler through the latter part of April and into May and June. Growers struggled with annual ryegrass burndown control. Rains returned as we turned the page into summer and crops responded well. Concerns over the wheat and barley crop, which appeared uneven through he late spring, were unfounded. The small grain crop was of great quality and yield. Growers struggled during the later harvest period as rains delayed harvest well into July. Most corn made it through the pollination window with adequate moisture. Dry conditions returned once again in August and September, resulting in drought stress to beans and corn. Corn harvest started a little earlier than normal. Overall yield reports are above average, and something to be grateful for given the dry conditions later in the season. Beans were more of a mixed bag. Early planted beans performed well for the second year in a row, with most of the crop made by the time the rain ran out. Double crops beans ranged from very poor to very good depending on rain timing and stage of beans. The fall harvest season has been good. Wheat and barley has germinated well and is growing fast with warmer than normal fall temperatures.—Ben Beale, St. Mary’s Co.

*Regions (counties):
Western: Garrett, Allegany, Washington. Central: Frederick, Montgomery, Howard. Northern: Harford, Baltimore, Carroll. Upper & Mid Shore: Cecil, Kent, Caroline, Queen Anne, Talbot. Lower Shore: Dorchester, Somerset, Wicomico. Southern: St. Mary’s, Anne Arundel, Charles, Calvert, Prince George’s

2023 Maryland Tar Spot of Corn Research

Andrew Kness, Senior Agriculture Agent | akness@umd.edu
University of Maryland Extension, Harford County

Summary

Tar spot is a new foliar fungal disease of corn first discovered in the United States in 2015 and confirmed in Maryland in 2022 and was estimated to be the most significant yield-limiting disease of corn in the US in 2021 and 2022. As a new disease for our state, this project collected preliminary data on the distribution of tar spot in our state and compared the efficacy of different fungicide application timings. Through field surveys we identified and confirmed tar spot in eight Maryland Counties at a frequency of approximately 47% and at a relatively low severity rate (not exceeding 30%). These observations suggest that the tar spot pathogen can overwinter in Maryland, as it has expanded its range from two counties in 2022 to at least eight in 2023. Field evaluations of two fungicide programs: one pass program at VT and a two-pass program at VT followed by R2, we observed a significant difference in tar spot severity and plant lodging compared to the control; however, there was no difference in yield. Additional research on fungicide timing and the spread of this disease should be conducted in the future to help develop improved management recommendations.

Survey of Tar Spot Distribution in Maryland

Several fields were scouted for tar spot starting during late vegetative growth stages and frequency and intensity of scouting was increased from tassel through harvest. Initial scouting was focused in fields in Harford County near fields where tar spot was confirmed in 2022. In addition, reports were solicited from other Extension Agents and crop consultants/scouts throughout the state. Suspected positive samples were confirmed by laboratory technique and all positive samples were uploaded to the tar spot tracker map on corn.ipmpipe.org.

The first reported and confirmed incidence of tar spot in Maryland for 2023 came from a corn field in Cecil County on August 22. The second came from Carroll County on August 31, followed by Harford County on September 3. We confirmed tar spot in the additional counties of Kent and Queen Anne’s on September 19; Baltimore County on September 22; Caroline County on September 25, and Dorchester County on October 6 (Figure 1).

Figure 1. Map showing confirmed distribution of tar spot for the 2023 growing season (yellow). Map from corn.ipmpipe.org.

Several fields were scouted in Northern Harford County throughout the year surrounding fields where tar spot was confirmed in 2022. By the end of the season, tar spot was found in over 50% of these fields (9/16) at levels ranging from 2% to 25% severity (Figure 2). It was observed that tar spot severity continued to increase after black layer for as long as there was green, living tissue remaining on the plants. This increase in severity after physiological maturity does not affect yield but does make for a notably increased level of severity present at harvest and thus the potential for an increase in overwintering spores that will provide inoculum for the following year.

Figure 2. Corn leaf with approximately 10% tar spot severity. Tar spot symptoms include raised, black specks on the leaves.

An additional survey of 12 fields on Maryland’s Eastern Shore from Cecil to Queen Anne’s County was conducted on September 19. During this time, two fields were confirmed with tar spot. Severity was very low (<2%) in the field in Queen Anne’s County, and high in the field in Kent County (30%).

Altogether, tar spot was confirmed in 16 out of 34 fields (47%) scouted/reported throughout the state (Figure 3), with samples coming from as far west as Washington County (no confirmed samples) east to Cecil County (two confirmed samples) and south on the Maryland Eastern Shore as far as Dorchester County (one sample confirmed).

Figure 3. Google Earth map of fields scouted (blue markers) and confirmed (red markers) presence of tar spot. Markers are approximate locations and not precise to protect the identity of the landowner and/or farmer.

Weather conditions were favorable for tar spot on the Eastern Shore and Northern Maryland; however, severe drought conditions from Frederick County west may have prevented its widespread establishment in Western Maryland.

Based on this survey, tar spot appears to be established in all the northern counties east of Frederick and south on the Eastern shore to at least Dorchester County, at a frequency of approximately 40-50%. Judging by the confirmed occurrences in other counties in different states, it is likely that tar spot is present in more Maryland Counties than determined by this survey.

On-Farm Fungicide Trials

Fungicides are an effective management tool for foliar diseases of corn, including tar spot. Research from the Midwest has shown a positive response to fungicide applications in fields where tar spot disease severity is high. However, there is debate as to if one fungicide application made around VT is sufficient to control tar spot, as yield losses have been reported as late as R4. In 2023 we established an on-farm trial to evaluate the response to a single fungicide application compared to a two-pass program for managing tar spot in corn.

Field plots were established at a farm in Harford County, MD in a field immediately adjacent to where tar spot was found in 2022. Corn (Revere Seed ‘1307 TCRIB’) was no-till planted into soybean residue with a John Deere 1775 NT ExactEmerge™, 30-inch, 16 row planter at the rate of 35,000 seeds/acre. Rows 1, 2, 15, and 16 on the planter were shut off to create alleys between adjacent plots and to eliminate treatment overlap, as well as to ensure harvest accuracy. This resulted in 12-row plots that were between 75 and 150 feet long. Plots were arranged in the field in a randomized block with three treatments and five replicates (Figure 4).

Figure 4. Tar spot fungicide timing research plot layout.

Fungicides (Table 1) were applied at the VT and R2 growth stages using a DJI T30 drone calibrated to deliver 2.8 gallons per acre spray volume to the entire length of the 12-row plots. VT applications were made on July 12 and R2 applications were made on August 5. Trivapro 2.1 SE was used for all applications. Trivapro was selected because previous research has demonstrated that multi-mode-of-action products have the best efficacy against tar spot.

Table 1. 2023 Fungicide Treatments.

Treatment Product Name

Active Ingredient(s)

Application Rate (& Timing)
Nontreated Control N/A N/A
1X Pass Trivapro 2.1 SE

Benzovindiflupyr + Azoxystrobin + Propiconazole

13.7 fl oz/A (VT)
2X Pass Trivapro 2.1 SE

Benzovindiflupyr + Azoxystrobin + Propiconazole

13.7 fl oz/A (VT) & 13.7 fl oz/A (R2)

Foliar diseases were rated prior to fungicide application and approximately every two to three weeks following until harvest. Disease severity from tar spot was visually rated as the percent leaf area infected in the canopy from 10 random plants from the center two rows of each plot.

Lodging scores were collected at harvest by conducting a “push test” on 10 plants from the center two rows of each plot. The push test consists of pushing a corn plant approximately 30 degrees from vertical; plants that break have compromised stalk strength and were considered lodged.

Yield data were collected by harvesting 12 rows of each plot using a John Deere S780 combine on October 13, 2023. Yield data was exported from the combine monitor and RTK was used to correlate yield with plot locations since we were not able to collect individual plot weights. All yields reported are adjusted to 15.5% moisture. All data were analyzed using ANOVA and significant differences between treatments were separated using Fisher’s Least Significant Difference (LSD; α=0.10).

On-Farm Trial Results

Tar spot was first observed in the plots on August 29 present at a very low level (less than 2% severity). Overall tar spot disease severity was low throughout the season in these plots. One possible explanation for this is the early planting date, which likely allowed the corn to complete its critical reproductive growth stages before weather conditions were favorable for tar spot development.

Early disease ratings revealed a significant difference in tar spot severity (p=0.0176) in treated plots vs nontreated plots (Table 2). However, late disease ratings collected at harvest show an overall increase in tar spot severity, but no difference between treated and nontreated plots. This is likely due to the fact that fungicides can only offer around 14-21 days of protection. In this trial, the second fungicide application did not provide improved tar spot control compared to the single pass treatment; however, the single fungicide application at VT delayed tar spot infection compared to the nontreated control.

Table 2. 2023 Tar Spot Disease Rating and Harvest Data.

Treatment Tar Spot Severity (%) Lodged Plants (%) Grain Yield (bu/acre) Grain Moisture (%)
9/11/23 10/12/23
Control 3.05 a* 3.75 10.0 a 192.56 19.06
1X Pass 1.18 b 2.88   5.0 a 199.05 19.41
2X Pass 0.85 b 4.00   0.0 b 201.56 20.31
p-value 0.0176 0.4133 0.0680 0.2123 0.4343

*Treatments connected by the same letter are not significantly different from each other (α=0.10).

The control plots averaged 192.56 bu/acre with a low of 169.7 and high of 214.6; the single pass (1X pass) program yielded an average of 199.05 bu/acre with a low of 177.5 and high of 228.6 bu/acre; and the two-pass (2X pass) fungicide treatment yielded an average of 201.56 bu/acre with a low and high of 194.4 and 222.7 bu/acre, respectively. However, there are no statistically significant differences in yield between treatments (p=0.2123). Likewise, there was also no significant difference in grain moisture. Tar spot disease severity was relatively low; likely too low to impact yield in this trial, leading to no yield response.

The 2X pass fungicide program did improve standability of the crop at harvest, with 0.0% lodging, significantly better than the 1X program (5.0%) and the control (10.0%).

This work was supported by funding through the Maryland Grain Producer’s Utilization Board and in-kind support from The Mill. Special thanks to Clear Meadow Farm for their use of land and equipment making this research possible.

2022 Soybean Fungicide Trials

Andrew Kness, Senior Agriculture Agent | akness@umd.edu
University of Maryland Extension, Harford County

Trials were established at the Wye Research and Education Center in Queenstown, MD (WYE), Central Maryland Research and Education Center in Ellicott City, MD (CMREC), and Western Maryland Research and Education Center in Keedysville, MD (WMREC) in 2022 to assess the efficacy of select fungicides for the suppression of soybean foliar diseases. Soybean ‘MAS3521E3’ were no-till planted into soybean residue at 150,000 seeds/A on 1 Jun at WMREC and 31 May at CMREC and WYE. All plots were 30 feet long and arranged in a randomized complete block design with 5 replications. Data was collected from the center 5-ft of each plot. The trial consisted of eight foliar fungicide treatments and a non-treated control. Fungicides were applied with a backpack CO2-pressurized sprayer. Fungicides were applied at the R3 growth stage on 5 Aug at CMREC and WYE and 8 Aug at WMREC. Treatments with subsequent applications were made 14 days later. Yields were collected by harvesting the center 5-ft of each plot and adjusted to 13% moisture. Plots were harvested on 8 Nov at WYE, 18 Nov at CMREC, and 22 Nov at WMREC. Data were analyzed using ANOVA, and significant differences between treatments were separated using Fisher’s Least Significant Difference (LSD; α=0.10).

The most predominant foliar pathogen at all locations was frogeye leaf spot (Cercospora sojina); however, growing conditions were generally very favorable and no disease was observed at a ratable level. This is likely due to the weather conditions around pod fill, as well as the resistance package in the soybean variety, which has a frogeye leafspot resistance rating of 7 on a 10-point scale (10 being the most resistant). Yields were above average, and no significant differences were observed between treatments at any location. No phytotoxicity was observed with any of the fungicide treatments. Data for 2023 is being processed and will be uploaded to the Agronomy News Blog once available. This work was funded by the Maryland Soybean Board.

Treatment, rate/A

and timing

Grain Moisture (%)   Test Weight (lb)   Yield (bu/A)
WMREC CMREC WYE   WMREC CMREC WYE   WMREC CMREC WYE
Non-treated control 10.6 12.6 10.7   54.7 56.3 54.3   78.4 72.1 52.0
Headline 2.09 EC/SC, 6.0 fl oz at R3 10.5 12.2 10.5   54.7 56.5 54.4   91.0 74.0 59.8
Veltyma 3.34 S, 7.0 fl oz at R3 10.5 12.5 10.5   54.2 56.5 54.3   90.3 72.0 70.9
Miravis Top 1.67 SC, 13.7 fl oz at R3 10.6 12.2 10.5   55.4 54.0 54.3   86.5 63.0 59.2
Adastrio, 8.0 fl oz at R3 10.5 12.7 10.5   54.9 55.4 54.7   84.6 58.0 58.0
Revytek 3.33 LC, 8.0 fl oz at R3 10.6 12.4 10.4   54.9 55.2 54.3   82.3 76.1 62.9
Revytek 3.33 LC, 8.0 fl oz at R3 fb

Revytek 3.33 LC, 8.0 fl oz 14 days after R3

10.6 12.7 10.5   54.8 55.4 54.2   83.6 58.9 60.9
Lucento 4.17 CS, 5.0 fl oz at R3 10.5 12.4 10.5   54.6 55.4 54.4   83.4 67.2 62.6
Lucento 4.17 CS, 5.0 fl oz at R3 fb

Lucento 4.17 CS, 5.0 fl oz 14 days after R3

10.6 12.4 10.5   54.6 55.7 54.4   81.9 64.0 55.5
p-value 0.8716 0.3464 0.7067   0.2440 0.7375 0.9531   0.6583 0.7095 0.3133
z Means followed by the same letter are not significantly different based on Fisher’s Least Significant Difference (LSD; α=0.10).

Optimizing Early Season Pest Management for Maryland Field Corn

Maria Cramer, PhD Candidate and Kelly Hamby, Entomology Extension Specialist
Department of Entomology, University of Maryland

Background

Research Questions

  1. Are the NST Poncho 250® and the in-furrow pyrethroid Capture LFR® effective at controlling pests and increasing yield in high-input (Bt) or low-input (non-Bt) field corn in Maryland?
  2. Do Poncho and Capture hurt slug predators and flare up slug damage?

Study Design

In order to capture the range of pest pressures and growing conditions in Maryland, we replicated our study across 3 UMD research farms (Keedysville, Beltsville, and Queenstown) and over 3 years (2020-2022). At each location we planted one field of a Bt hybrid and one field of a similarly-yielding non-Bt hybrid as early as possible in the growing season (Table 1). In 2020 our Bt hybrid was LC1196 VT2P (Local Seed, Memphis, TN) which expresses Cry1A.105/Cry2Ab2 proteins. In 2021 and 2022 we planted P1197YHR (Pioneer Hi-bred International. Johnston, IA) which contains Cry1Ab and Cry1F proteins. We planted P1197LR (Pioneer Hi-bred International, Inc. Johnston, IA) for our non-Bt hybrid all three years. All hybrids had excellent yield potential and were grown with standard no-till practices. In each field we established 3 replicates of 3 treatments at planting: 1) an untreated control, with bare seed and no in-furrow product, 2) an in-furrow pyrethroid treatment using Capture LFR® (active ingredient: bifenthrin, rate: 13.6 fl oz/acre), and 3) an NST treatment using Poncho® (active ingredient: clothianidin, rate: 0.25 mg/seed). Each replicate consisted of 24 rows of corn at 30 inch row spacing, and was 200 feet long.

Year Location Planting date Sampling dates
2020 Keedysville May 18 June 8
Beltsville May 21 June 10
Queenstown May 13 June 3 and 4
2021 Keedysville May 14 June 1 and 3
Beltsville May 17 June 2
Queenstown May 4 May 25 and 26
2022 Keedysville May 26 June 10
Beltsville June 2 June 21
Queenstown May 12 May 31

Question 1: Are the NST Poncho 250® and the in-furrow pyrethroid Capture LFR® effective at controlling pests and increasing yield in high-input (Bt) or low-input (non-Bt) field corn in Maryland?

Data Collection

In order to evaluate how the treatments affected pest pressure, we visually sampled V2-V3 corn for types of pest damage (Figure 1), recording the number of plants and area damaged. We counted the number of healthy and stunted plants to determine if the treatments impacted stand. Because neonicotinoids can sometimes stimulate plant growth unrelated to pest damage7,8, we measured plant height to determine if plant growth was impacted by either treatment. At the end of the growing season, we measured stand again and harvested the corn to collect yield data.

Figure 1. Diagnostic seedling pest damage: a) soil pest, b) cutworm, c) armyworm, d) slug, e) stinkbug, f) miscellaneous feeding damage from a spotted cucumber beetle.

Results and Takeaways for Question 1

Poncho reduced insect damage more consistently than Capture LFR (in both Bt and non-Bt corn) and increased Bt corn stand. Capture LFR sometimes reduced insect damage (in non-Bt corn), but never improved stand.

We compared the number of seedlings with any type of pest damage between treatments and found that Poncho decreased damage about 62% in Bt corn and about 66% in non-Bt corn (Figure 2a and 2b). Compared to the control, Capture did not reduce damage in the Bt corn, but did reduce damage by about half in the non-Bt. Poncho increased stand about 8% compared to control in the Bt corn (25,731 ± 456 plants per acre and 23,623 ± 714 plants per acre, respectively), but did not improve it for non-Bt. Capture did not impact stand for either Bt or non-Bt corn.

Figure 2. Mean % ± SE of seedling A) Bt and B) non-Bt corn plants damaged by pests. Data were collected across three UMD research farms from 2020-2022. Within each graph, treatment bars with different letter above them are significantly different from each other.

There were no yield benefits from using either insecticide in either corn. This was likely due to a lack of economic pest pressure.

Non-Bt and Bt yields were the same across treatments (Figure 3A and 3B). This was probably because pest pressure was so low. Even though Poncho and Capture decreased pest damage, pests were below treatment thresholds—for example, armyworm damage in the control ranged from 0% to 5.4% of Bt plants, and 0% to 22.9% of non-Bt plants, in both cases below the treatment threshold of 35%9. Cutworm damage was similarly low ranging from 1% to 6.3% in Bt control and 0.5% to 3.8% in non-Bt control, also below the treatment threshold of 10% feeding damage9.

Figure 3. Mean yield ± standard error in bushels per acre corrected to 15.5% moisture of A) Bt corn and B) non-Bt corn. Yield data from 2020-2022 across three UMD research farms. Treatments did not significantly impact yield.

Takeaway: Pest pressure and yield were similar between the Bt and non-Bt varieties, and non-Bt yielded well without any insecticides. In general, without pre-existing pest problems in a given field, at-planting insecticides are unlikely to pay off in Maryland.

Question 2: Do Poncho and Capture hurt slug predators and flare up slug damage?

Data Collection

To assess the effect of treatments on slug biocontrol agents, we measured slug predatory ground beetles and predation. We measured predatory beetles with pitfall traps for three consecutive weeks. Because the predators that eat slugs also attack caterpillars, we used sentinel caterpillars to see how much predation was occurring (Figure 4). We placed sentinel caterpillars in the plots overnight, collected them the following morning, and assessed signs of damage from predators. To determine if slugs were flared up by the treatments, we measured slug abundance once a week for 6 weeks beginning between 14 to 21 days after planting and measured slug-damaged seedlings during V2-V3.

Figure 4. Sentinel caterpillars placed in field overnight and collected in the morning to determine predator activity.

Results and Takeaways for Question 2

Predation on sentinel caterpillars was not decreased by insecticides.

We measured the percent of sentinel prey that were damaged by predators overnight (Figure 5) and saw no relationship between treatment and predation rates (Figure 6). This suggests that the insecticides did not decrease predator activity in treated plots. We did generally see some level of predation all weeks at our locations, indicating that predators are usually present in seedling corn.

Figure 5. Top: predators feeding on sentinel prey. Bottom: examples of damaged prey proportions. Images: M. Cramer, University of Maryland.
Figure 6. Mean ± SE % sentinel prey caterpillars consumed across three UMD research farms from 2020-2022. Control, Capture, and Poncho did not significantly differ.

Predator abundance was not altered by insecticides.

When we measured the weekly counts of ground beetles, we found similar results between treatments. This was true when we looked at all ground beetles (predators, omnivores, and seed-eaters), as well as when we looked only at predatory beetles (Figure 7A and 7B).

Figure 7. Mean ± SE count of A) all ground beetles, and B) specifically predatory ground beetles, caught per week in pitfall traps across three UMD research farms from 2020-2022. No significant differences.

Slug natural enemies did occur throughout the study, suggesting that biocontrol could be more intentionally leveraged.

The two most abundant ground beetle species in our study were both predators. One of these species, Chlaenius tricolor (Figure 8) is a slug predator that consumes slugs in agricultural ecosystems5,10. Although its abundance was not affected by treatments, it was present at all locations in all years, suggesting that it is a particularly important slug natural enemy in Maryland crops.

Figure 8. Chlaenius tricolor, a slug predator that was found throughout the study. Photo credit: ©Molanic 2023: https://www.inaturalist.org/photos/314013175.

Neither insecticide increased slug abundance or slug damage.

If treatments had negatively affected predators, we would expect to see more slugs and damage in the insecticide plots. However, when we compared slug counts between treatments, we found that the insecticide treatments were not different from the control (Figure 9). Slug damage to the seedling corn was also similar across the control and insecticide treatments (Figure 10).

Figure 9. Mean number of slugs per replicate plot ± SE the week closest to seedling sampling across three UMD research farms from 2020-2022. No significant differences.
Figure 10. Mean ± SE % of corn seedlings damaged by slugs across three UMD research farms from 2020-2022. Control. No significant differences.

While slugs can be damaging in many crops, the worst slug damage in our study did not affect corn stand or yield, suggesting that corn is generally tolerant of slug damage at the levels we observed in this study.

Slug damage was scarce across years and locations except in 2021 at Keedysville. Even in that case where a high proportion of seedlings (42% ± 4% on average) were damaged by slugs, we did not see an associated decrease in stand or yield. Corn seedlings were able to outgrow the slug damage as the weather warmed, even when they appeared severely defoliated. The seedling resilience we observed is supported by work on hail damage in corn which shows that as long as the growing point is intact, corn can regrow from complete defoliation11.

Even though we did not see non-target effects in this study, both pyrethroids and neonicotinoids can decrease natural enemies in crop fields6,12–14.

Acknowledgments

We would like to thank the farm managers and staff of WYEREC, WMREC, and CMREC Beltsville for their expertise and assistance. We would also like to thank the Hamby lab’s many undergraduate researchers for helping complete this project with all their hard work.

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