Computer Modeling of the Perennial Groundcover System

The Perennial Groundcover (PGC) system is a potential shift away from conventional land management and crop production in the U.S. Unlike traditional cover crops that are terminated and replanted annually, the PGC system provides year-round living cover that grows simultaneously with row crops. PGC has all the benefits of traditional cover crops, including erosion control, water retention and nutrient conservation, but extends these benefits to the entire year.

My research as a FFAR Fellow at Iowa State is focused on modeling the ecosystem services in this novel system. Field trials, while essential, are limiting because they can’t include a broad range of scenarios. Modeling allows us to move beyond the limits to simulate, test and forecast the behavior of PGC across various climates, soils and management practices. Yet, modeling PGC is not a plug-and-play endeavor. Because the system involves growing two plants simultaneously, we need to adapt known parameters (like soil moisture, leaf area index etc.) and calibrate new ones (like grass planting operation, soil layer thickness etc.) to fit existing process-based models like Environmental Policy Integrated Climate (EPIC) and Agricultural Production Systems Simulator (APSIM).

What makes this research effort unique is the collaborative foundation on which it is built.  

As a FFAR Fellow, I’ve come to appreciate the power of relationship-building, how to work and communicate across different personality types and the way interdisciplinary collaboration fuels better science. The PGC project is truly team science in action, harnessing the strengths of plant breeders, seed scientists, soil ecologists, social scientists, engineers and policy researchers. While “team science” sounds great in concept, researchers need to ground the concept in concrete practices where collaborators can freely interact often. Every Friday, we gather in what we call “Friday Café,” a casual, cross-functional space where I, as a modeler, get to ask questions and absorb insights from other teams and vice versa. These conversations often lead to clarity and better objective deliveries for the work.

It was through one of these collaborations that we realized the need to incorporate runoff and erosion monitoring into our existing field plots. This effort wasn’t part of our original project scope. To fund the addition, I applied for and secured a mini-grant to support a summer rainfall simulation study from Iowa State University’s Water Security Initiative (now Water Resilience Collaborative).

That study has since become important to understand the nuances of modeling this new PGC system and what to change going into the future. One key takeaway from the experiment is the compelling evidence of PGC’s potential, including a 90% reduction in soil erosion and a 60% reduction in runoff.

Bolstered by the excellent scientific communication skills I learned as a FFAR Fellow, I have been able to translate technical findings into impactful stories for broader audiences. I’ve had the honor of presenting to over 50 farmers during field days across Iowa, all thanks to a collaboration with Dr. Dan Andersen, an Extension Professor at Iowa State. From Black Hawk to Boone, I shared how the PGC system is saving soil and lowering water loss in farm fields. After one session, an attendee asked for help in implementing an erosion control strategy. I shared a mini-guide on how to set up a simple, low-cost erosion pad tailored to their plot. It was an experience that I will value forever.

The research has also led me to test species like Poa bulbosa, a grass that goes dormant during the summer, minimizing competition for light, water and nutrients while it re-emerges in the fall, an ideal candidate for long-term perennial cover. We have used the erosion pad tech to track sediment transport and better quantify nutrient loss.

To ensure our work continues to advance, I have taken on leadership roles that strengthen our RegenPGC network. I owe some of this to the preparation and confidence-building I’ve experienced as a FFAR Fellow. I led a team of graduate students in organizing guest lectures and initiated a field visit to The Land Institute (TLI) in Salina, Kansas, where we connected with Dr. Brandon Schlautmann to exchange ideas on perennial systems. These experiences have deepened my understanding of the plant side of the model which is crucial for someone with an engineering background.

Leveraging my mentor network within the FFAR Fellows, I was invited by one of my mentors, Luis Jurado, to present to his Sustainability and Outreach Team in the Digital Farming Solutions group at Bayer. That meeting generated ideas on making our models more accessible not just to scientists, but also to farmers.

I look forward to a future where we can turn the model into a smartphone application, allowing farmers to estimate how much their investment in a PGC leads to savings by limiting erosion and runoff. This could all be done directly from the field, using localized data and simple interfaces.

Ultimately, building robust ecosystem models isn’t just about codes and calibration; it’s also about working with people. Understanding what experts in plant breeding, soil health, genetics and social systems are doing helps refine the assumptions we make in our models and ensures our outputs are grounded in reality. Being able to communicate clearly across research areas and develop trusting relationships are critical for the kind of innovation that can regenerate America’s working landscapes for generations to come.