2016 Annual Report for ONE16-281c
Nitrogen contribution from cover crops for vegetable crop uptake
Summary
Years of research on nitrogen contributions from cover crops to following cash crops have been conducted all over North America, but farmers still struggle to manage timely nitrogen (N) release from cover crops on their own land to match their cash crop peak demand. Managing N demands of vegetable crops on diversified farms in New England is particularly challenging given the high crop diversity with different nutrient needs (amounts and timing). Prior research resulted in the development of the Pre-sidedress Nitrate-nitrogen Test (PSNT) as a tool for nitrogen management in corn. We believe that the same test may be used effectively to monitor N mineralization from various cover crops to improve timing of N contributions to other vegetable crops beyond corn. There are over 1,400 vegetable farms in Massachusetts covering over 17,700 acres (USDA Agriculture Census, 2012) who could benefit from improved cover crop management and use of soil nitrate testing to determine crop N sufficiency. This proposed project will evaluate cover crop mixtures with diversified vegetable farmers to measure nitrogen availability and sufficiency in the spring to subsequent summer cash crops.
Objectives/Performance Targets
The main goals of this project are: 1) to expand evidence based N management for vegetable farmers who plant cover crops and 2) select cover crops with N mineralization rates that best match cash crop demands.
Project activities
Demonstration trials
Five farmers who participated in an August 2016 workshop conducted by the MA SARE state program titled “How to conduct an on-farm trial” will be trained in implementing the specific trial for this project on their own farms in the Fall of 2016. The project team will distribute cover crop seed at the beginning of the trial, assist in cover crop establishment, and review methods for rating % ground cover. At the time of cover crop incorporation in May of 2017, the team will visit each farm again to collect biomass samples and receive training in PSNT sampling protocols. Experimental design will be identical for all farms (except for one “farmer choice” cover crop treatment) in order to gather a large data set and to simplify implementation of this project.
Educational activities
A field walk will be hosted on 2 of the farms conducting the trial in 2017 and the farmers will present their experience with the trial (expected attendees: 10 Agricultural Service Providers and 30 Farmers). Advertising events and results of this trial will be published in Vegetable Notes and Crops, Dairy, Livestock Newsletter. Event notifications will also be distributed by MA team member mailing lists such as: NRCS, Southeastern MA Agricultural Partnership (SEMAP) and the New England Vegetable and Berry Growers Association (NEVBGA). Trial results will be published in 2 Extension publications reaching over 3,000 subscribers and submitted to HortScience if conducted for 2 years.
Accomplishments/Milestones
Appendix: 2016 Annual Report Nitrogen contribution from cover crops for vegetable crop uptake
| Date | Planned Task | 2016 Annual Report Update |
| September, 2016 | Deliver seed and assist farmers in planting cover crop trials at 5 farms around MA | Plots were seeded between August 26th – September 8th, 2016 on 6 farms across MA (see Fig.1 map attached). A baseline soil sample was taken from all locations before seeding and we expect differences in pH, organic matter, and starting soil nitrate levels among locations to affect the mineralization of N in this trial next season (Table 1). |
| Sept 2016 – May 2017 | Farmers collect % ground cover data from trials monthly | Percent cover was rated using Canapaeo Phone App and visual ratings by the farmer in October and November, 2016. Differences were observed among treatments within and between farms. Farmers guessed that their ‘Farmer Choice’ treatments often had better coverage or more biomass than the rye/vetch treatment and wondered how weed coverage would affect N mineralization next season. (Figure 3 a and b) |
| May 2017 | Incorporate cover crops and collect the following data with farmers (biomass, tissue analysis, C:N ratio, soil nitrate) | Biomass samples were taken from all plots with any plant matter that will winter kill: annual weeds, oat, pea, tillage radish. Biomass was weighed and will be analyzed for nutrient content to calculate C:N ratios and total N becoming available over winter. Data not available yet. |
| May 2017 | Incorporate cover crops and collect the following data with farmers (biomass, tissue analysis, C:N ratio, soil nitrate)- | |
| May-July 2017 | Farmer takes soil nitrate samples from each treatment biweekly 4 times over a period of 8 weeks and ships samples to UMass for analysis.- | |
| June-July 2017 | Plant cash crop and rate vigor: 2 weeks and 4 weeks after transplant or germination- | |
| August-October 2017 | Rate yield and Host 2 Field Walks or Twilight meetings on participating farms.- | |
| December 2017 | Present results of trials at New England Vegetable and Fruit Conference or at a NEVBGA winter meeting along with farmers and educators from other states who conducted similar trials. Publish results in Vegetable Notes.- | |
| 2017-2018 | Repeat the trials if more funding is made available and possibly submit paper to HortScience in December 2018.- | |
Collaborators:
Graduate Student, Research Assistant
Stockbridge School of Agriculture
University of Massachusetts
Amherst, Massachusetts 01003
UMass Extension Faculty
Stockbridge School of Agriculture, Crop Dairy Livestock Equine
University of Massachusetts
Amherst, MA 01003
Resource Conservationist
Natural Resources Conservation Service
451 West Street
Amherst, MA 01002
Langwater Farm
Route 138
North Easton, MA 02356
Graduate Student, Research Assistant
Stockbridge School of Agriculture
University of Massachusetts
Amherst, MA 01003