New technologies for improving sustainability of corn N management

New technologies for improving sustainability of corn N management

Summary

This project aims to enhance N management while also increasing the adoption of cover crop and soil health management practices in corn production. The Adapt-N tool was validated using 113 paired field strip trials conducted in New York and Iowa during the 2011- 2014 growing seasons. In 93 of 113 trials (82%) the Adapt-N tool recommended lower N application than the respective Grower rate, with an average reduction of 45 kg ha^-1(34%). These reduced rates resulted in an increased profit in 83 of the 113 trials (73%), and an average increase of $65 ha^-1 over the Grower rate (See attached figure) when all trials were considered.  While recommending lower rates, average yield was not significantly different between Adapt-N and Grower rates therefore Adapt-N provides the opportunity for a win-win scenario, as applying a more precise rate at each location results not only in producer profits, but also in decreased GHG losses, and reduced N losses to surface and groundwater.

Adapt-N was licensed at the end of 2013 and became available for commercial use in the spring of 2014.  Walmart named Adapt-N the top-rated nitrogen management tool, it has been praised by the Environmental Defense Fund and was recently named a winner in General Mill’s Global Innovation Challenge, which aims to reduce the environmental impacts of farming. We have collected most of the 2015 trial data and are in the process of gathering the rest and beginning analysis.  We offered new indicators for the Soil Health Assessment in 2015 and for the first time offered a new, “basic” assessment as a streamlined introductory alternative to the comprehensive assessment. In 2016, we will begin examining how data from soil health assessments can be used in a beta version of Adapt-N to better inform recommendations. We continue to make progress educating stakeholders about the importance of adapting N inputs in corn systems to weather impacts by moving to dynamic N rate decisions made at sidedress time, and about the contributions of soil health to nitrogen dynamics through outreach and field demonstrations. 

• Profit differences between Adapt-N and Grower Conventional Practice over 4 yrs of trials

Objectives/Performance Targets

By 2015, users will simulate locations representing 80,000 corn acres in Adapt?N, and will implement recommendations on at least 20,000 acres. Although dependent on seasonal conditions, environmental losses through leaching and denitrification are expected to be reduced by 40%, saving on average 40 lb N/acre over conventional recommendation systems. Participating farmers will realize estimated savings of at least $550,000 and prevent over 800,000 lb of excess N from polluting the environment.

Accomplishments/Milestones

• 1500 farmers and advisors gain understanding of dynamic, in?season N management with tools like Adapt?N and multi?purpose/high?clearance equipment for sidedressing and cover crop establishment, through field days, winter meetings, and newsletterarticles. 1,602 achieved by December 2015
• 300 farmers and advisors learn the above and also how to use Adapt?N and the new preliminary cover?crop module through webinars, and 80 of these will also gain in?depth knowledge of Adapt?N use in 2 intensive hands?on workshops provided by the team. (Feb?Apr 2014). As of 10/30/15 there were 50 collaborators with grower accounts and 13 Ag Service Providers with accounts on the research version of the tool alone. Specific numbers on Adapt-N users on licensed accounts are not available to us at this time but every indication is that this business is adding users. We are very close to achieving this milestone if we haven’t already.

• 30 new farmers and 10 new advisors request accounts to use the updated Adapt?N version in 2014. (Jan?June 2014) See above. We cannot access licensed accounts at time of reporting, but every indication is that the business is growing.
• 12 farmers, working with 8 project collaborators, implement strip trials, comparing current N management with Adapt?N rates, gaining direct experience and training with dynamic, in?season N management. (Apr?Nov 2014) As of December 2015 we have accomplished this milestone during 2014 and 2015. In 2015 we worked with 12 project collaborators who in turn worked with 34 farms implementing 41 field trials.
• 15 additional farmers implementing CIG funded cover?crop inter?seeding trials in MD, PA and NY learn how to use Adapt?N and implement Adapt?N rates using the new covercrop module. (Apr?Nov 2014) The CIG Funded project was completed in 2014. Research was completed and code was written for including cover crop information but the user interface is still in development. We are dependent on the private company who licensed Adapt-N to decide to include this update into their software. We continue to work with them to get this in there.
• At least 50 users answer end?of?season survey questions on their experience with Adapt?N. (Mar 2015) As of 10/30/15 there were 50 collaborators with grower accounts and 13 Ag Service Providers with accounts on the research version of the tool. Specific numbers on Adapt-N users on licensed accounts was not available at the time of reporting but every indication is that this business is adding users. The survey is in the process of being developed.
• 1500 farmers and advisors learn about Adapt?N performance results from prior growing seasons, and updated cover cropping and soil health indicator input features, through 4 field days and 4 fall/winter meetings (Aug 2014?Mar 2015) 1,602 achieved in 2015 through 9 field days and 14 summer/fall/winter meetings
• 300 farmers and advisors will gain in?depth understanding through webinars, training modules and 2 further in?depth workshops including hands?on interactive material. (Aug 2014?Apr 2015) The 12 advisors affecting 34 farms was achieved in 2015. Since the tool has been licesensed, some of the education responsibilities have transferred to them. However, we published the Adapt-N manual in 2014 (http://adapt-n.cals.cornell.edu/manual/pdfs/adapt-n-manual.pdf) and held a webinar in March 2015 to 20 Ag Service Providers. Work continues to prepare training modules for 2016.
• 150 new growers and 20 new consultants sign up to use the enhanced Adapt?N version, better incorporating cover crop and soil health effects, by 2015. As of 10/30/15 there were 50 collaborators with grower accounts and 13 Ag Service Providers with accounts on the research version of the tool alone. Specific numbers on Adapt-N users on licensed accounts are not available to us at this time but every indication is that this business is adding users. We are very close to achieving this milestone if we haven’t already.
• For 20 locations, farmers shift N applications to later in the season, and/or will use multi?purpose/high?clearance equipment to apply N and/or plant cover crops. (Apr?Aug 2015) As of 10/30/15 there were 50 collaborators with grower accounts and 13 Ag Service Providers with accounts on the research version of the tool alone. Specific numbers on Adapt-N users on licensed accounts are not available to us at this time but every indication is that this business is adding users. We are very close to achieving this milestone if we haven’t already.
• At least 100 users reply to an end of season survey on their experience with and implementation of Adapt?N (Nov?Dec 2015) This survey is in development and will be distributed in winter 2016.

Outreach/Education

Adapt-N was licensed to Agronomic Development Corporation and is now available as a commercial tool (Adapt-N.com).  This has greatly expanded the reach of the tool through (i) significant software improvements and (ii) professional marketing.  Adapt-N now operates as a “public-private partnership” where Cornell University remains responsible for the research component and scientific enhancements, and ATC focuses on the business aspects.  This has worked very well, as ATC remains committed to the scientific integrity of the tool and acreages being used continues on an upward trend.

To date, over 200 strip trials have been conducted on commercial farms to test the Adapt-N tool and function as demonstration trials. For the 2015 trial season we continue to  work with 5 Ag Service providers (IA,IL,NY,MD) 5 University Extensionists (ME,NY,VT) and 2 research farms (NY).  We communicated with advisers and collaborators on the progress of field trial implementation and to collect Adapt-N results. In addition, we continue to receive feedback from collaborators on the utility of the Adapt-N Tool. 

Over 20 presentations have been given at various outreach events, including field days, winter meetings, conferences, and scientific meetings, with an approximate total audience of 3,000 people.  In addition, we are actively working with other organizations like Environmental Defense Fund as part of the NutrientStar evaluation process, and also to perform Adapt-N simulations in the context of the development of policy recommendations.  We have communicated regularly with NRCS leadership in Washington, DC (Honeycutt, Widman, etc.) about updates related to Adapt-N. 

We have published several newsletter articles in 2015 that demonstrate Adapt-N’s usefulness in monitoring N availability and provide precise N recommendations in the field in addition to using it as a modeling tool to demonstrate how Adapt-N can reduce environmental losses and how dynamic N rate tools for corn compares to static ones. Furthermore, we have prepared and submitted an academic paper titled “Adapt-N Outperforms Grower-Selected Nitrogen Rates in Northeast and Midwest USA Strip Trials” to the American Society of Agronomy Journal.

Research and Adapt-N Improvements

The tool’s accuracy and precision have been evaluated through on-farm trials and improved in response to performance and user feedback.  As of December 2015 we have successfully completed 200 trials, either involving side-by-side comparisons (Adapt-N vs Grower-selected) or multiple N rates. The results are very positive, and provide direction for improvement.  Adapt-N performs well when used correctly, and can improve profits while reducing environmental losses through leaching and denitrification (win-win). We have been able to reach more than the target number of professionals on the use and benefit of the Adapt-N approach.  We have achieved high exposure throughout the US corn growing region, and Adapt-N is regarded as a leading dynamic N management tool. We have been able to complete the training sessions and reach many professionals.  The strip trials indicated that farmers and consultants require guidance on the use of the tool, especially as it relates to yield estimates.  The tool performed very well when the yield goals were well estimated.

In addition, a significant research effort is being completed to improve the soil water and drainage code in the Adapt-N model.  Artificially-drained soils will be simulated through a computational routine based on the Hooghoudt equation, which will allow for better simulation of N dynamics on artificially-drained soils.  Other model upgrades related to water flow and N dynamics have also been implemented (e.g., denitrification constraints by soil wetness).

• Outreach at research farm field day

Impacts and Contributions/Outcomes

The economic optimum N rate (EONR) that a corn crop needs is highly variable from year to year and field to field, and this is heavily influenced by weather, especially by early-season rainfall. The project team recommends that producers and their service providers use the Adapt-N tool to aid in N rate decision making at sidedress time, and as a learning tool to guide more in-depth understanding of N dynamics and management options. 

Primary beneficiaries of Adapt-N are Northeast and Midwest corn producers using a variety of management styles and scales (Adapt-N is scale-neutral), but particularly those who already have sidedressing equipment. However, many of our collaborators report that the Adapt-N tool, and associated learning opportunities, are encouraging growers in their area to shift N application toward sidedressing, away from pre-plant application. The project is also benefiting agricultural service providers including consultants, extension personnel, NRCS and SWCD staff, and researchers, who can use the tool to teach about N dynamics and to provide better N management advice. Society is a secondary beneficiary through improved water quality, reduced greenhouse gas losses, and mitigation of climate change associated with better N management on the most common and environmentally impactful crop in the U.S. Using average N savings of 44 lb/ac and an approximate 100,000 acres using Adapt-N recommendations, 2015 use of the tool can be estimated to have reduced the amount of N applied to these fields by over 4,000,000 pounds, saving producers a total of at least $2-3M. 

In 2015 we continued our field trials in collaboration with Agronomic Technology Corporation. We will use existing data to examine the relationship between yield in zero-N or low-N field plots and soil health to calibrate and improve performance of the initial soil health beta-module, which will be available in the research-version of Adapt-N (not commercially available in 2015). We will provide new model calibrations based on these data, as well as feedback for necessary or suggested user-interface improvements, to our collaborators at ATC. They will implement user- and research-informed enhancements to the tool for each new growing season.  For the 2016 year, we are also expecting a cover crop module in Adapt-N, which is highly anticipated by NRCS staff.

The ability of the Adapt-N tool to adjust sidedress N rates to account for early season weather was demonstrated for the 2013 season in New York and Iowa. At the NY 2013 trials, heavy rainfall events occurred shortly following the crop planting, when large amounts of mineralized N and early applied N were vulnerable to losses. Adapt-N accounted for these weather effects and recommended higher N sidedress rates in 81 of the 113 trials (72%) compared to the Grower-selected rates (an average increase of 22 kg ha^-1). Trial number 24 is a prime example of this (see attached figure). Similar to a third of the trials in the NY 2013 season, the Grower in this trial chose to rely solely on large pre-plant application (197 kg ha^-1) to supply crop N requirements. Following planting, a series of heavy rainfall events (a) led to large simulated N losses and the soil became mostly depleted of available N by the middle of the growing season (b). In the absence of an additional sidedress application, the deficit in soil N led to a low seasonal crop N uptake of 89 kg ha^-1 (b). In contrast (c), Adapt-N recommend an additional sidedress N application of 67 kg ha^-1, which replenished soil N deficits and led to a 99% increase in the simulated seasonal crop N uptake and an increase of 2605 kg ha^-1 (42 bu ac^-1) in measured yield compared to the Grower (c). Overall, higher rates were recommended by Adapt-N for the 2013 NY trials. These results demonstrate that an adaptive N management approach that accounts for weather effects can be highly profitable, especially during years with high early-season precipitation.

The project team concludes that use of the Adapt-N tool for informing sidedress application rates in corn should be strongly recommended and widely implemented in corn systems. New York and New Hampshire NRCS have already written the Adapt-N tool into their advanced 590 nutrient management practice options, and there is potential for the tool’s use to be widely incentivized through cost-shares by NRCS, non-profit, and other organizations. Implementing such additional incentives along with the inherent risk- and profit-related incentives from Adapt-N will aid in improving water quality, decreasing greenhouse gas emissions, and helping producers adapt to variable early season weather and maintain profitability on broad acreages.  All recent publications are available on our website (http://adapt-n.cals.cornell.edu/pubs/index.html).

• Adapt-N adjustments to sidedress N recs in wet season leads to increased yields

Collaborators: