Evaluating the Use of Forage Radish to Enhance Winter Rye Cover Crop Performance

2015 Annual Report for GNE14-091

Project Type: Graduate Student
Funds awarded in 2014: $14,998.00
Projected End Date: 12/31/2016
Grant Recipient: University of Vermont
Region: Northeast
State: Vermont
Graduate Student:
Faculty Advisor:
Dr. Sid Bosworth
University of Vermont

Evaluating the Use of Forage Radish to Enhance Winter Rye Cover Crop Performance


As farmers in the northeast are faced with an ever mounting pressure (and desire) to protect water quality, increase soil health, and maintain productive and sustainable farms; they are increasingly turning to cover crops as a way to accomplish these goals. By far the most common cover crop utilized by dairy and forage crop farmers in Vermont is winter rye seeded after corn silage. With our short growing seasons, winter rye has become a dependable cover crop to provide good erosion control and nutrient cycling. However, as more producers become aware of alternative cover crop species and mixtures of species, they are asking to know more about their choices and what the potential benefits may be to planting these alternative crops. This study is evaluating whether the addition of forage radish to a winter rye cover crop could augment and enhance the performance over winter rye by itself. In addition, it will quantify the economic impacts of this combination and basic agronomic recommendations for seeding rates and establishment methods.

This field experiment will occur on two farms over the course of two seasons. Plots were no-till drilled and broadcast after timely corn silage harvest and then received one application of liquid dairy manure immediately after planting. Measurements occurred the fall after planting and the subsequent spring. Results will be shared with farmers and ag service providers in Vermont and around the northeast. There is a large Extension/outreach component to this project. This project is part of a larger USDA-NIFA project.

Objectives/Performance Targets

Objective 1: Determine the effects of combining forage radish with winter rye cover crops and evaluate if the addition of forage radish has impacts on: overall performance of the cover crop, improved nutrient uptake and enhanced ecosystem services.
Progress to date: Spring data was collected from the 2014-2015 plots. This included percent cover, plant height, biomass yield, plant tissue mineral analysis, soil nitrogen, regular soil chemistry analysis, soil temperature, air temperature, soil moisture, soil compaction and pictures. 2015-2016 plots were planted and fall data was collected on those plots. This included plant population counts (emergence by species), baseline soil chemistry analysis (by block), percent cover, air temperature, plant height, biomass yield, and plant tissue mineral analysis. Data is still be entered and analyzed. However the project coordinator has completed her graduate statistics course and is currently analyzing the 2014-2015 data.

Objective 2: Establish the proper seeding rates and planting methods for a forage radish/winter rye cover crop in a corn silage system with manure.
Progress to date: The second year of research commenced during this reporting period. All plots were successfully planted at identical rates and species as the previous year’s experiment. This year, one site is on Vergennes B clay soil, and will provide a good comparison to other site locations with lighter soils. One site was planted earlier than last year on September 9th, while the other was planted very similar timing to last year on September 22nd. All plots had good emergence and establishment.

Objective 3: Quantify the economic impact of different cover crop treatments, both seeding rates/composition and application methods.
Progress to date: Seed cost data and establishment costs are being monitored. Once final data is completely processed and analyzed, we will be able to compare the economic ramifications of those results in conjunction with costs of cover crop establishment for each treatment.

Objective 4: Promote and increase the use of cover crops and share project findings through direct farmer outreach with field days, newsletter articles, social media, Extension fact sheets and presentations. Provide research-based data to support of modify existing cover cropping specifications being used by technical service providers and cost share funding agencies.
Progress to date: As the first year’s data is analyzed, those results will be shared at upcoming conferences and meetings in winter 2016. In 2015, the following outreach occurred:


    • 2015 Vermont No-Till and Cover Crop Symposium, preliminary project information was shared with the 175 attendees. (February 2015|Burlington, Vt.)




    • Soil Health Workshop & Field Day hosted by Champlain Valley Crop, Soil & Pasture Team (CV Crops) with 55 attendees (38 farmers, 10 service providers, 7 agency/govt./university), which included presentations and a field portion focusing on compaction and soil biology, utilizing cover crops to reduce phosphorus runoff, and the economic viability of cover crops. (April 2015 | Vergennes, Vt.)




    • Two CV Crops email newsletter issues featured articles about cover cropping written by the Project Coordinator. One (‘Learning As We Go’) focused on the importance of farmer participation in cover crop research and the other (‘Sponge or Stone: Cover Crops & Wet Weather’) looked at the role cover crops play in farm resilience in extreme weather. This newsletter is distributed to over 700 readers via email and another 425 through regular postal service. (July 2015 and October 2015)




    • A ‘Crop Patrol’ was hosted in conjunction with Champlain Valley Farmer Coalition at the Vorsteveld Family Farm (project participant) looking at the practice of injecting manure to incorporate broadcast seeding of winter rye, oat and radish cover crop following corn silage harvest. The event was attended by 6 farmers, 2 agriculture business representatives and 4 extension staff. (September 2015 |Panton, Vt.)




    • Another Crop Patrol was hosted with CVFC at Cher-Mi Farm looking at several different mixes of cover crops including winter rye, barley, winter peas, and forage radish. There were 6 farmer, 2 agriculture business, 3 agency and 3 extension attendees. (October 2015 |Orwell,Vt.)




    • The CV Crops team hosted a Fall Soil Health Workshop & Field Day at Foster Bros. Farm with guest speaker Ray Archuleta. The Project Coordinator presented preliminary project information during the morning classroom session and then led the field portion of the day looking at a related project with 16 different combinations of cover crops in demonstration plots. The event had 82 attendees with 40 farmers, 11 ag industry professionals, 17 agency staff and 14 Extension/University faculty/staff. (October 2015 | Middlebury, Vt.)



2015 marked the second successful planting season for this research project. Spring entailed collecting final data on the first year’s plots. As we processed fall forage samples, we realized that many of the plots did not have sufficient sample to be processed at the lab. This was particularly true for the broadcast seeded plots, the plots that did not receive manure, and the radish roots that we had collected as part of the root/shoot analysis. Where this was the case, we consolidated samples by treatment by site. For example the samples from all 4 replications of Treatment #1 (112 lbs of winter rye broadcast) from the Clifford East site were combined for tissue mineral analysis. Where there was sufficient sample quantity for all four replications, samples were analyzed individually. For the Spring 2014 and Fall 2015 forage sampling, we did not encounter the same problem. We increased our subsamples from four to six and weather/growing conditions were conducive to good plant growth. The weather in May 2015 was particularly nice. Farmers planted corn earlier than usual. This did impact the project in that we were only able to collect one set of biomass/tissue analysis samples from the Clifford East site as the farmer planted his corn on May 9th. We were able to get a second set of those samples on the Clifford West site prior to cover crop termination.

The 2015 cropping season was unique due to its very nice May conditions that led to earlier than normal corn planting. That was followed by excessive June precipitation, but normal to above average growing degree days. Corn harvest tended to be early where planting occurred early, but yields were lower than expected in many areas of the Champlain Valley with heavier soils. Needless to say, we were able to capitalize on the early corn harvest and plant the first of our 2015 cover crop plots right on target on September 9th. Conditions were very dry, almost to the point that we delayed planting. However, we went ahead and planted. I believe early growth was inhibited by dry conditions, but the late onset of winter made up for that. Our last sampling occurred also right on target in the first two weeks of November. In hindsight, we could have continued to sample plots all the way through December. Follow-up visits to the plots revealed the rye and radishes continued to put on growth at least until Christmas when we saw temperatures above 60-degrees. We should see the results of that in our spring sampling, however.

There were a few small changes in the project in the 2015 plantings. We continued to work with Clifford Farm in Starksboro. However, instead of Conant’s Riverside Farm being our second research site location, Vorsteveld Family Farm in Panton was chosen. This was primarily because they were already showing serious interest in the radish/winter rye combination by planting it on 800 acres, and also because they had an extraordinarily early corn harvest (September 3rd). In addition, they have partnered with the UVM Extension CV Crops Team on other projects and have proven to be reliable and progressive research/demonstration partners. Another added bonus is that we have a great working relationship with their custom manure spreader, which also made that part of the project more practical. The only other unexpected event was that the Clifford site was unable to get the planned liquid manure application. The custom manure spreader was unable to make it to Starksboro immediately after we planted the cover crop plots (September 22nd), and by the time he made it to the farm the plants had germinated but were likely too small to handle the heavy field traffic. We opted to skip the manure application as opposed to risk destroying the plots. While this was unfortunate, we will be able to compare these ‘unmanured’ plots to the extra plots in the 2014-2015 plantings that did not receive manure. In addition to a regular manure application history, the baseline soil analysis from these plots shows adequate fertility for Phosphorus, Potassium and other macro and micronutrient. Spring soil nitrogen sampling should pick up any deficiencies in nitrogen if they exist. All plots had good emergence and fall growth at both sites. We also decided to change the orientation of the plots to go across the corn rows instead of with them. This facilitated more consistent and efficient manure spreading over the plots.

Overall the project is progressing well. The only field work left will be spring sampling that should be identical to Spring 2014 sampling. After that, there will be a lot of data analysis, summarizing and wrapping up the project. This project is the Master’s Thesis for the Project Coordinator. The goal is for the thesis defense to be in December 2016. This project has already proven to be a great catalyst for further research and demonstration projects.

Below is a summary of work in 2015.

Spring 2015
2-Apr: Relaunched air temperature data loggers at both sites
15-Apr: Collected soil nitrogen samples, soil temperatures (2” and 4.5”), soil moisture (Clifford EAST-drilled/control)
16-Apr: Collected soil nitrogen samples, soil temperatures (Clifford WEST-drilled/control)
16-Apr: Joshua Faulkner (UVM Center for Sustainable Agriculture) installed real-time soil moisture sensors @ Clifford West plots 2, 3,7,8, 10, 11 to beta test sensors
21-Apr: Spring Soil Health Workshop & Field Day (Vergennes, Vt.)
30-Apr/1-May: Collected percent cover and soil moisture measurements on all plots
2-May: Took pictures of all plots
5-May: Collected forage biomass samples, plant height, soil temperature and compaction measurements (Clifford EAST)
6-May: Collected forage samples, plant height, soil temperature and compaction measurements (Clifford WEST-drilled/control)
7-May: Collected soil nitrogen samples, regular soil samples, prepped nitrogen samples at AETL (Clifford EAST-drilled/control)
8-May: Collected soil nitrogen samples, regular soil samples, prepped nitrogen samples at AETL (Clifford WEST-drilled/control)
9-May: Eric Clifford no-till planted corn through all plots in Clifford EAST, left flags in place, then terminated cover crop with herbicide. Pulled air temperature data loggers.
14-May: Collected second round of forage biomass samples on plots (Clifford WEST)
29-May: Weighed dried samples, stored in grinding room @ Hort Farm
11-16-Jun: Ground all dried/weighed samples
June: all forage samples inventoried, sent to lab for tissue analysis (crude protein (N), Phosphorus, Potassium), met with Alan Howard (UVM) to go over data processing for proper statistical analysis

Fall 2015
Aug/Sep: Met with Eric Clifford, David Conant, Gerard Vorsteveld to discuss project and identify potential field locations
7-Sep: Weighed out all seed for broadcast plots
8-Sep: Scoped out field locations at Vorsteveld Farm (Panton), made maps, updated grain drill calibration notes
9-Sep: Flagged all plots, planted all plots, talked to Gerard Vorsteveld and Eric Severy regarding manure application
10-Sep: Prepped for manure calibration, programmed air temperature data loggers
11-Sep: All plots received surface manure application, measured manure application rate, collected manure weights/density measurements, collected manure samples for lab analysis, installed aier temperature data loggers, baseline soil samples were collected (by block) prior to manure application (Vorsteveld)
15-Sep: Crop Patrol at Vorsteveld Farm looking at manure injection and rye/oat/radish cover crop establishment.
18-Sep: Scoped out field locations at Clifford Farm (Starksboro)
22-Sep: Prepped and flagged field, planted around outside of experiment area (Clifford)
23-Sep: Planted all plots
29-Sep: Checked emergence (Vorsteveld)
2-Oct: Collected plant population counts, percent cover, pictures for all plots (Vorsteveld)
2-Oct: Launched air temperature data loggers, once it was determined manure would not be applied (Clifford)
7-Oct: Checked emergence (Clifford)
15-Oct: Collected plant population counts, percent cover and pictures for all plots (Clifford)
23-Oct: Crop Patrol at Cher-Mi Farm (Orwell) looking at cover crop mixtures no-till drilled following corn silage harvest.
28-Oct: Fall Soil Health Workshop & Field Day (Middlebury, Vt.)
4-Nov: Collected plant height, percent cover, soil moisture and compaction on all plots (Vorsteveld)
6-Nov: Collected forage biomass samples, pictures on all plots (Vorsteveld)
10-Nov: Collected forage biomass samples, percent cover, heights on all plots (Clifford)
20-Nov: weighed, ground biomass samples @ Hort Farm (Vorsteveld)
24-Nov: Took pictures of all plots (Clifford)
25-Nov: weighed, ground biomass samples @ Hort Farm (Clifford)
1-Dec: All tissues samples sent to lab for tissue analysis (crude protein/Nitrogen, Phosphorus, Potassium)
9-Dec: Checked plots, radishes still growing (Vorsteveld)

Impacts and Contributions/Outcomes

This project, in conjunction with 16 other cover crop research/demonstration projects that were planted this year, is definitely having an impact in the farming community in Addison, Chittenden & Rutland counties of Vermont (and beyond). This year we saw increased adoption of cover crops by farmers in the Champlain Valley and increased use of diverse species. One example is a farm, who is also a project participant, which planted a mixture of winter rye, oats and forage radish on over 800 acres. Particularly significant is that this farm received cost-share dollars for only 200 of those acres. We are seeing more and more of this every season. Another farm that had been only planting winter rye, added tillage radish to his cover crops on two fields, and he utilized our no-till drill to plant them. Another farm that has not been planting cover crops after corn silage planted 30 acres of different cover crop mixes to see what works best on his farm, and then allowed us to host a ‘Crop Patrol’ farmer field day to let other folks take a look. One farm in Addison County used forage radish as a nurse crop for a new alfalfa seeding. A positive impact has been the willingness for farmers to share what they are trying with other farmers. Innovation is catching on and farmers are sharing the information and knowledge they gain with each other. Cover crops are definitely on the rise, and that makes this particular research project even more useful for farmers adopting that practice and going above and beyond the basics. I look forward to doing a lot of data analysis and conveying what we learn with northeast growers. I am happy to be participating in research that has been so well received by the farmers implementing these practices.


Jeffrey Carter

Agronomy Specialist: Field Crops & Nutrient Management
UVM Extension
23 Pond Lane, Suite 300
Middlebury, VT 05753
Office Phone: 8023884969
Website: http://www.uvm.edu/extension/cvcrops
Eric Clifford

Clifford Farm
6147 VT Route 116
Starksboro, VT 05487
Office Phone: 8024343810
Gerard Vorsteveld

Vorsteveld Family Farm
Jersey Street
Panton, VT 05491
Dr. Sidney Bosworth

Extension Professor
University of Vermont
208 Jeffords Hall
63 Carrigan Drive
Burlington, VT 05405
Office Phone: 8026560478
Website: http://pss.uvm.edu/vtcrops/