Interest in growing soybeans in far northern regions continues to increase as farmers adapt to disruptive fluctuations in markets, climate, and farm economics. Despite this interest, there is limited research-based information on production methods for soybeans in this region. To overcome these economic and environmental challenges, farmers need region-specific agronomic information to maximize soybean yields while enhancing conservation efforts. This project meets the Eastern Region Soybean Board priorities of high yielding soybeans and soil health. Through the project research trials will be initiated to determine best varieties for the northeast and cover cropping practices will be evaluated to determine their feasibility in soybean systems. Research material will be delivered to farmers through local conferences, field days, and online webinars. The project is expected to deliver soybean research to over 800 stakeholders.

Objective 1 is to identify soybean varieties that produce maximum yields in the far north. Working with seed companies and farmers in the region, we will identify 20-30 short season soybean varieties in maturity groups 000 to 2. The experimental design will be a randomized complete block with 3 replicates. Data to be collected will include yield, moisture, test weight, oil content, and oil yield. Soybeans will also be monitored for pest and disease pressure through routine scouting.
Objective 2 is to develop cover crop termination strategies for soybean production systems that maximize yield, protect soil health, and minimize pest and disease pressure. This objective will investigate the impact of cover crop termination method and residue or cover crop biomass level on soybean yield and soil health. The experimental design will be a randomized complete block with split plots and four replicates. Main plots will be cover crop termination methods including tillage and herbicide applied before or following planting. Sub-plots will be varying levels of cover crop biomass created by seeding winter rye at rates ranging from 0 to 150 lbs/acre. Data to be collected will include weed pressure, slug and insect pest pressure, soybean establishment, soil health metrics, soil moisture and nutrient content, and soybean yield and test weight.
Objective 3 is to develop interseeding strategies for soybean production systems that protect soil health while supporting high soybean yields. This objective will investigate the impact of interseed timing and species selection on cover crop establishment success, soybean yield losses, and soil health. The experimental design will be a randomized complete block with split plots and four replicates. Main plots will be interseed timings that coincide with best planting dates for winter rye and annual rye grass should coincide with the R6-R8stage of soybean development. The subplots will be cover crop species (no cover, winter rye, or annual). Data to be collected will include soybean yield, cover crop establishment, ground cover, and biomass, and soil health metrics.

The information produced through through the research projects will be shared broadly through our extensive Extension contact network. We will highlight the project at our annual Crop and Soil Field Day and No-Till Cover Crop Symposium, which attract a combined 500 attendees from around the region. Project results will be summarized into farmer-friendly reports that will be published to our website and linked to social media. In the event that the pandemic continues we will shift to virtual outreach methods. In addition, one YouTube video will be produced to highlight cover crop termination and interseeding strategies in soybean production systems. Research findings will also be made available at winter conferences and outreach events held throughout the region. We expect to reach an audience of at least 800 stakeholders.

Updated August 27, 2021:
Due to continued economic and climatic pressures, farmers in the Northeast are looking for ways to increase on-farm feed production and diversity their operations to increase resilience and profitability. Soybeans could be grown for human consumption, animal feed, and biodiesel in Vermont. However, farmers face challenges due to the relatively short growing season and limited research-based information available in our area. The purpose of our trials is to evaluate soybean yield and quality to determine cover cropping management practices that enhance soil health while supporting high soybean yields. Understanding how soybeans perform under various cropping systems can help producers make important management decisions that lead to better crop success. With a growing concern of agriculturally related water quality implications in Vermont waterways, farmers are now required in some instances to cover crop their annually cropped fields. However, with this increase in cover cropping there is a need to investigate potential impacts on following cash crops and best practices for establishing cover crops into and following soybeans. Similarly, with the concerted effort to reduce nutrient loading in waterways due to soil erosion, farmers are becoming more interested in adoption reduced and no-till practices. Understanding how to best combine these two practices into soybean cropping systems specifically for the Northeast is critical to the success of soybean crops in Vermont.

This year we initiated several soybean trials at Borderview Research Farm in Alburgh, VT. These trials include a variety evaluation trial, a cover crop trial in which soybeans follow fall planted cover crops under varying tillage regimes, and a soybean interseeding trial. This report will summarize our research and outreach activities around these trials thus far this season.

Variety Evaluation Trial

The conventional variety trial includes 29 varieties from four different seed companies spanning maturity groups 0.70 to 2.4. The trial was planted on 25-May 2021 into a Benson rocky silt loam at a rate of 185,000 seeds ac-1 treated with soybean inoculant and with 5 gal ac-1 9-18-9 liquid starter fertilizer. Throughout the season the trials were inspected for insect and disease issues however due to extremely hot and dry conditions very little disease and insect pressure has been seen thus far. With recent rainfall, we have been observing instances of downy mildew. We will continue to monitor the trials and will conduct additional assessments to capture differences between varieties if warranted. The trials will also be evaluated for populations, yield, and quality upon harvest.


Cover Crop Trials

In the fall of 2020, four cover crop seeding rate treatments, summarized in table 1 below, were planted at Borderview Research Farm in Alburgh, VT on 6-Oct. Rates ranging from 50 to 150 lbs ac-1 of winter rye and a no cover crop control were used to produce varying levels of cover crop biomass leading to varying levels of residue that precedes soybean planting the following spring. These four treatments were replicated four times each within three termination systems: conventional tillage, pre-plant herbicide application with no tillage, and post-plant herbicide application with no tillage. Establishment of the cover crop was later than normal due to overly dry conditions extending field preparation and delaying planting. Due to this later planting, no biomass was collected in the fall of 2020.

In the spring of 2021, soil health samples were taken from four replication from each of the seeding rate treatments including the control. Samples were collected according to the Cornell Soil Health Laboratory protocol and were submitted to that laboratory for analysis. At this time, biomass was collected in each plot within a 0.25m2 quadrat on 12-May in the plow and pre-plant herbicide blocks, and on 21-May in the post-plant herbicide block. Ground cover was also captured at this time using the Canopeo smartphone application. Soil moisture and temperature were measured in each plot at approximately 6” prior to planting and every other week following planting.

Ground cover and biomass increased with seeding rate as expected, however statistical analysis has not yet been performed to determine if these differences are significant. Soil moisture was approximately 2% higher in the control plots than all the cover cropped plots prior to planting. This suggests that, in years with wet springs cover crops can help absorb and utilize excess soil moisture which may allow for earlier field preparation. However, it is also possible that, in dry years, this could be detrimental to crop establishment. To investigate this, we continued to take soil moisture and temperature reading every other week to track changes across treatments throughout the growing season. In addition to soil moisture, soil temperature was measured prior to planting. Although little difference was seen between treatments prior to planting, difference in soil surface residue could influence soil temperature over the season. These data will be analyzed for the final report.

Cover crop residue was incorporated into the soil in the plow block with disc harrows and the soil finished for planting with a spike-tooth harrow on 12-May. In the pre-spray block, cover crops were terminated using an application of Roundup® PowerMax herbicide at a rate of 1 qt. ac-1 on 12-May. Finally, cover crops were terminated with a post-planting application of Roundup® PowerMax at a rate of 1 qt. ac-1 on 22-May. Soybeans were planted in all plots on 21-May at a rate of 185,000 seeds ac-1, treated with soybean inoculant, and planted with 5 gal ac-1 9-18-9 liquid starter fertilizer. To understand the nutrient release rates of the various levels of cover crop biomass and how this is impacted by termination method, soil nitrate content was assessed in each plot prior to termination and biweekly following termination and planting. At this time these analyses have not all been completed. Soil temperature and moisture were also measured weekly in all plots to understand differences between cover crop and tillage treatments. The soybeans were also scouted for slug damage in early June to investigate differences between residue levels and potential slug harboring habitat between termination methods and cover crop treatments. However, with dry conditions persisting from late spring through early summer no slug damage was observed in any treatment. Soybeans will continue to be monitored for insect and disease pressure and will be evaluated for populations, yield, and quality at the time of harvest.

We also plan to implement a soybean interseeding trial this fall. Specific details surrounding treatments and experimental design have yet to be solidified, however, a topic of interest to farmers in our region is interseed timing. Soybeans typically reach maturity and are harvested beyond the optimal times for establishing cover crops, even the most hardy and vigorous species like winter cereal rye. Therefore, looking towards other establishment strategies that can be utilized pre-harvest, such as interseeding, could provide farmers opportunities to be able to implement cover cropping to aid their conservation and soil health promoting efforts (Figure 2). Compared to post-harvest seeding, interseeding presents additional challenges related to equipment and timing seeding with crop growth stage to avoid damage while getting good establishment. Soybean plants that are too young and bushy may be damaged by equipment pushing them over if interseeding occurs too early. Conversely, if done too late, shattering damage may occur. We plan to investigate the efficacy of interseeding cover crops at various growth stages leading up to harvest in order to identify practices that support both high soybean yields and successful cover crop establishment.

Outreach
Outreach this year has continued to be very difficult. Our main mode of outreach during the summer months typically are workshops and field days attracting hundreds of farmers, technical service providers, and other agricultural professionals. Similar to last year, with most in-person events still unable to occur, we continued to provide farmers with valuable, research-based, and season relevant information through other modes of communication. Reports summarizing our research have been posted to our website (links below) and shared through our blog and social media networks. On August 4, we were able to host an on-farm field day in Franklin, VT. The participation had to be capped at 75 due to COVID-19 restrictions. Farmers were able to learn about previous soybean research and also view variety evaluation plots. A second workshop will be held in October and will focus on cover cropping and other conservation practices across multiple cropping systems including soybeans. At the conclusion of our season, we will still create research reports which will be made available through our website and in-print in our office. In lieu of conferences if we cannot hold them this winter, we will continue to prioritize performing cover cropping, no-till, and soybean production outreach to our farmer and agricultural professional stakeholders to the best of our abilities.

View uploaded report

Updated March 31, 2022:
As farmers in the far northeast region look for ways to reduce feed costs and diversify their operations, soybeans are becoming increasingly popular. However, these farmers need region specific information to help them succeed in producing high yielding soybean crops while protecting the natural resources on and around their farms.

This project met several of the Eastern Soybean Growing Region Board research priorities including a focus on high yielding soybeans and soil health.

All projects were conducted in the most northwestern corner of VT. The soil type is characterized as a silt loam with 1 to 2% slope. The weather during the 2021 growing season can be characterized as warm and dry. Above average temperatures and below average precipitation persisted throughout the growing season.

Objective 1 was to identify soybean varieties that produce maximum yields in the far north. The experimental design was a randomized complete block with 3 replicates. The treatments were 19 varieties with maturity groups ranging from 0.7 to 2.8.

The average yield for the entire trial was 62.3 bushels of soybeans per acre. The top performing variety yielded 73.7 bushels per acre and had a maturity grouping of 2.0. Other varieties that performed statistically similar to this top performer had maturity ratings ranging from 1.2 to 2.8.

The data from this growing season indicates that high soybean yields can be obtained from a wide range of maturity ratings in far northern regions. However, it is important to note some large differences between varieties even within similar relative maturities. For example, the three varieties with relative maturity 1.2 ranged in yield from 46.9 to 71.4 bu/acre. These data highlight the importance of utilizing local variety evaluation information in variety selection.

Objective 2 was to investigate the impact of cover crop termination method and residue or cover crop biomass level on soybean yield and soil health. The experimental design was a randomized complete block with split plots and four replicates. Main plots were cover crop termination methods including tillage, herbicide applied before planting or planting green where herbicide is applied following planting. Sub-plots were varying levels of cover crop biomass created by seeding winter rye at rates ranging from 0 to 150 lbs/acre.

The seeding rates of winter rye had little impact on the soil health and soybean yields. However, the termination treatments had a much greater influence on soybean yields. The plant green block was terminated a week later and produced statistically higher biomass compared to the other two treatments. The plant green treatment had statistically lower yields, about 1.3X less, compared to the tillage and pre-plant herbicide treatments.

As noted earlier, the entire growing season was dry. The additional cover crop biomass and longer period of growth likely dried out the soil more than the other cover crop treatments. Since rainfall was in a deficit all season, the plant-green plots may have been more water stressed than the other treatments. Average, across the season soil moisture was significantly lower in the plant green plots. This additional moisture stress may have contributed to lower yields.

Objective 3 investigated the impact of cover crop interseeding dates timed with later soybean developmental stage R6-R8 on cover crop establishment. The experimental design was a complete randomized block with four replications and the treatments were four cover crop planting dates. Annual ryegrass (var. Centurion) was interseeded into soybeans at four different planting dates: 14-Sep, 21-Sep, 28-Sep, and 4-Oct. Soybeans were harvested on 27-Oct. A week after soybean harvest, percent ground cover from the cover crop and cover crop biomass yields were measured.
The annual ryegrass planting date had no significant impact on soybean harvest. Ground cover and cover crop yields were significantly impacted by planting date. The first planting date, 14-Sep, had statistically higher ground cover, 52.9%, and dry matter yield, 1426 lbs. or 0.71 tons/acre, compared to the other three planting dates. The latest planting date, 4-Oct, had the lowest ground cover, 13.6%, and dry matter yield, 235 lbs per acre. This trial indicates that interseeding cover crops a month prior to soybean harvest will provide for timely seeding and adequate cover crop establishment with hopefully minimal impact on soybean yield.

Soybean production information and research results were shared with over 300 growers and stakeholders throughout the region. Virtual events were still largely the avenue to share education on soybeans. However, in the fall of 2021 a fall field day was held drawing 126 stakeholders. Attendees were able to walk the research plots and learn about research results. Soybean cover cropping information was shared with farmers and service providers at the annual NECCC Annual Conference with 185 attendees. These soybean research materials including full soybean project reports will be continually available to growers and other interested parties through our website and shared at relevant virtual and in-person outreach events through 2022.

View uploaded report

As farmers in the far northeast region look for ways to reduce feed costs and diversify their operations, soybeans are becoming increasingly popular. However, these farmers need region specific information to help them succeed in producing high yielding soybean crops while protecting the natural resources on and around their farms. This project met several of the Eastern Soybean Growing Region Board research priorities including a focus on high yielding soybeans and soil health.

All projects were conducted in the most northwestern corner of VT. The weather during the 2021 growing season can be characterized as warm and dry. The first goal was to identify soybean varieties that produce maximum yields in the far north. We were able to evaluate 19 varieties with maturity groups ranging from 0.7 to 2.8. The top performing variety yielded 73.7 bushels per acre and had a maturity grouping of 2.0. However, the data indicates that high soybean yields can be obtained from a wide range of maturity ratings in far northern regions. It is important to note some large differences between varieties even within similar maturities. For example, the three varieties in maturity group 1.2 ranged in yield from 46.9 to 71.4 bu/acre These data highlight the importance of utilizing local variety evaluation information in variety selection. The second goal was to investigate the impact of cover crop termination method and cover crop biomass level on soybean yield and soil health. A range of cover crop biomass was created by seeding winter rye from 0 to 150 lb/acre. The cover crop termination methods included tillage, herbicide applied before planting or planting green where herbicide is applied following planting. The amount of cover crop biomass had little impact on the soil health and soybean yields. However, the termination treatments had a much greater influence on soybean yields. The plant green treatment was terminated later and produced more cover crop biomass compared to the other two treatments. The plant green treatment yielded 1.3X less, compared to the tillage and pre-plant herbicide treatments. As noted earlier, the entire growing season was dry. The additional cover crop biomass and longer period of growth likely dried out the soil more than the other cover crop treatments. Since rainfall was in a deficit all season, the plant-green plots may have been more water stressed than the other treatments. Average, across the season soil moisture was lower in the plant green plots. This additional moisture stress may have contributed to lower yields. Lastly, the impact of cover crop interseeding dates on cover crop establishment and soybean yields were evaluated. The cover crop interseeding was timed to occur between the R6-R8 stages of soybean development. The interseeding occurred on 14-Sep, 21-Sep, 28-Sep, and 4-Oct. Soybeans were harvested on 27-Oct. The annual ryegrass planting date had no impact on soybean harvest. Ground cover and cover crop yields were significantly impacted by planting date. The first planting date, 14-Sep, had statistically higher ground cover, 52.9%, and dry matter yield, 1426 lbs/acre compared to the other three planting dates. The latest planting date, 4-Oct, had the lowest ground cover, 13.6%, and dry matter yield, 235 lbs/acre. This trial indicates that interseeding cover crops a month prior to soybean harvest will provide for timely seeding and adequate cover crop establishment with hopefully minimal impact on soybean yield.

Soybean production information and research results were shared with over 300 growers and stakeholders throughout the region. Virtual events were still largely the avenue to share education on soybeans. However, in the fall of 2021 a fall field day was held drawing 126 stakeholders. Attendees were able to walk the research plots and learn about research results. Soybean cover cropping information was shared with farmers and service providers at the annual NECCC Annual Conference with 185 attendees. These soybean research materials including full soybean project reports will be continually available to growers and other interested parties through our website and shared at relevant virtual and in-person outreach events through 2022.

Farmers need region-specific agronomic information to maximize soybean yields while enhancing conservation efforts. This project will evaluate variety performance in northern New England. These are the only soybean variety trials in the region. This will provide farmers with critical information to aid with crop success. Farmers in the east are adopting cover crops to improve soil health, enhance farm resiliency, and meet environmental goals. Cover cropping is popular in corn and multiple strategies have been developed that work well in that crop production scheme. Farmers have been more challenged to find practices to successfully integrate cover crops into the soybeans. This project will continue to evaluate the impacts of cover cropping on the preceding soybean crop and also how best to integrate cover crops during the soybean year.