From North Carolina to ISU – Meet Preston

Preston Marrable

It’s summer, and we welcome another class of Undergraduate Research Interns. This year we have three interns. Today, meet Preston Marrable from North Carolina Agricultural and Technical State University. Preston will be working with RegenPGC CoPD Dr. Shuizhang Fei.

Preston’s goals for the summer are to “gain more knowledge and strengthen my work ethic and attention to detail. As much as I want to improve on a professional level, I also want to build friendly relationships with my fellow peers.”

We are pleased to welcome Preston to Iowa State University,  where we know he will learn a lot with Dr. Fei!

Meet Preston Marrable

Brief Bio. I grew up in Los Angeles while moving around Southern California as a kid. I currently live in North Carolina, and I attend North Carolina Ag & Tech State University as a rising junior. My favorite subjects are English and History. My personal hobbies are cooking, exercise, and listening to music. Something unexpected about me is that I went to Japan last year, and I enjoyed every minute of it.

Why I applied… I applied to the program because I want to gain research experience in STEM and mathematics. I also want to gain professional insight and experience by building a coalition of connections among my Iowa State colleagues before, during, and after the program has finished.

My expectations for the REU program include… I want to gain more knowledge and strengthen my work ethic and attention to detail. As much as I want to improve on a professional level, I also want to build friendly relationships with my fellow peers.

Malcolm Yusuf St Cyr completes his Master’s degree

Malcolm Yusef St Cyr Headshot

Today, we congratulate RegenPGC Graduate Education Community member Malcolm Yusuf St Cyr for his successful thesis defense and completion of his Master’s studies at Iowa State University under the mentorship of RegenPGC CoPd Dr. Marshall McDaniel. Learn more about Malcolm’s thesis, Perennial ground covers: A mitigation strategy to nitrous oxide (N₂O) emissions for maize cropping systems, at www.regenpgc.org/wp-content/uploads/2026/05/2026-05-19-StCyr-OFFICIAL-THESIS.pdf

ABSTRACT
Agricultural intensification in the U.S. Midwest has led to widespread of nitrogen (N) losses through nitrate (NO₃⁻) leaching and nitrous oxide (N₂O) emissions, two processes that threaten water and atmospheric quality. Traditional winter cover crops (WCCs) have proven to be effective in reducing NO₃⁻ leaching but remain limited in adoption due to economic and management challenges. Perennial ground cover (PGC) systems integrate non-leguminous perennial grasses in between annual row crops offering a potentially optimized alternative that maintains continuous soil cover without requiring annual replanting. However, their influence on soil nitrous oxide emissions and soil nitrogen and carbon pools remain poorly explored. In this study we used three PGC treatments: 1) Zea mays L. without PGC (Maize Control), 2) maize with Poa bulbosa, a summer-dormant grass commonly called bulbous bluegrass (Maize+BBG), and 3) maize with Poa pratensis, or Kentucky bluegrass (Maize+KBG) to analyze the impact of PGC on N₂O emissions and soil N and C pools. Both PGC treatments reduced interrow cumulative N₂O emissions by 38–81% relative to the control in both years (p < 0.01), although row-position emissions were more variable and influenced by fertilizer placement. Despite these consistent interrow reductions, field-level cumulative N₂O emissions were not significantly different among treatments in either year. Overall, our results indicate that PGC does not affect field-level soil N₂O emissions, while maintaining similar levels of plant-available N, and had no effect on maize yield.

It’s raining awards!

Memis Bilgici Award

They keep coming! Here is another award for a member of our RegenPGC Graduate Education Community. This time, it’s Memiş Bilgici who received an Iowa State University Research Excellence Award (REX).

Per the University, the award’s purpose is to “[…] recognize outstanding research accomplishments as documented in their dissertations. These students are also expected to be academically superior and able not only to do research but also to develop a well-written product. The intent of REX program is to recognize “the best of the best” graduating students who have submitted theses and dissertations.”

Congratulations to Memiş and his supervisor, Prof. Thomas Lübberstedt this significant achievement and recognition.

From Memiş: “I am deeply grateful to my supervisor, Prof Thomas LübbLübberstedtd to the RegenPGC community, with whom I have had the privilege to collaborate. I am proud of what we have accomplished together and excited to continue learning, building, and contributing to sustainable maize breeding, perennial ground cover systems, and controlled environment phenotyping.”

This is how we grow the future!

RegenPGC is a research program, and we define that term broadly, as we should. Every year, we help build the future by introducing existing and prospective science/STEM educators to our research portfolio.

We achieve this by participating in two crucial initiatives at Iowa State University: the Research Experience for Teachers (RET) and the Research Experience for Undergraduates (REU) programs. (https://lnkd.in/dC6HWes6). During the summer months, RegenPGC teachers and undergraduate interns become active members of our research team. This changes not only their lives but also positively impacts countless lives throughout their teaching careers as they apply their newfound knowledge directly to their classrooms.

Alex Haus, a 2025 Undergraduate Research Intern, is set to do the RegenPGC team proud when he presents his work at Wartburg College’s 15th RICE DAY (https://www.wartburg.edu/academic-affairs/rice/) on April 9, 2026. Alex’s poster, “How Perennial Groundcover Affects Maize Growth: Exploring Shade Avoidance Responses,” (https://www.regenpgc.org/wp-content/uploads/2026/03/RegenPGC-Poster-Template-med-QR.pdf), is a wonderful example of how interns can gain by working in a research team.

RegenPGC Team releases Year 4 Q 4 progress report

RegenPGC Yr 4 Q 4 Progress Report Cover

If it’s not documented … is it really complete? Who knows. However, here is our RegenPGC Year 4 Q4 Progress Report, and there is no doubt that we are learning more every day about perennial cover crops. You can access the report at https://www.regenpgc.org/wp-content/uploads/2025/11/RegenPGC-Yr-4-Q4-Progress-Report.pdf.

The report is written in a bulleted, friendly format and divided by topics so you can find your perennial cover crop passion right away! Check out our Research Objectives and Themes:

Objectives: Obj. 1. Crop Ecology & Management, Obj. 2. Plant Breeding & Genetics, Obj. 3. Soil Health & Nutrient Management, Obj. 4. Ecosystem Services, Modeling, Obj. 5. Socioeconomic Impacts & Policy and Project Evaluation

Themes:  Research and Development, Extension, Education, and Commercialization

Jack Moran thesis is available for download

Jack Moran Master's Thesis

RegenPGC graduate student Jack Moran’s master’s thesis, Improving the establishment of Kentucky Bluegrass as a perennial groundcover, is now available to download at https://lnkd.in/gRUhFFDs

Jack’s key research takeaway is: “Strategies such as using Hydroloc™ seed treatment and optimizing seed ratios and rates can significantly improve the establishment of Kentucky bluegrass as a perennial groundcover in corn production.”

Additional topics discussed include:
– Seed treatments for crop establishment
– Impact of irrigation on plant growth
– Economic considerations in agricultural practices

Learn more about Jack and the entire RegenPGC Graduate Education Community at https://www.regenpgc.org/theme-3-education/graduate-education-copy/

Meet Audrey Tucker, Undergrad researcher and trombonist

Audrey Tucker Headshot

Meet Audrey Tucker who come to RegenPGC via Wartburg College. Audrey brings something truly unique to the project… she is a trombone player.

My name is Audrey Tucker. I am 19 years old from Mount Vernon, Iowa. I am currently a first-year student at Wartburg College (Waverly, Iowa). I am studying biology and education and plan to have an endorsement in All-Science. I enjoy running, wrestling, reading, and hiking. Something unexpected is that I play the trombone at Wartburg.

I applied to the REU program because… it will be a good experience, and an amazing way to spend my summer. Participating in this program will help me use new tools to become a better teacher in the future. It could help me understand concepts, so I’m able to help teach students in the future and help others my age as well.

My expectations from the REU program are… for everyone to put in an equal amount of work, and questions, and not be afraid to make mistakes.

Why do you want to become a teacher? I was always frustrated in school because I never understood science. In my sophomore year of high school, my teacher helped me understand the content by drawing diagrams for me. Two years later, I had her as a teacher again. The first thing that she said to me that year was “I remember you learned by diagrams and drawings.” At that point, I realized that I wanted to be able to help students understand science just like my teacher. She made me enjoy science again. I want to be able to do that for others.

New ideas needed? Find them at RegenPGC!

It’s spring! It’s always a good time to be open to new ideas on managing our land and soil in row crop production. Our @RegenPGC Perennial Groundcover Project does precisely that. We are working on new approaches to a lot of old issues, such as how to:
◼ Reduce soil erosion (reduced P losses)
◼ Reduce water runoff
◼ Increase water infiltration
◼ Improve soil quality
AND
◼ How to achieve greater stover harvest

Our Project Director, Dr. Raj Raman, has some ideas on these topics, which he covers in this video presentation, “Perennial Groundcovers in Corn & Soybean Production Systems: Potential & Scalability.” You can find the video at https://youtu.be/MYQcSBZXVXQ  and the accompanying Field Notes at https://iastate.box.com/s/fij94zkojl6kpaofkmepdk66cpzb0ij3.

New RegenPGC Video Series

We realize some of you may be new to perennial groundcover and its potential for modern #agrictulture. So, we have started a new series to acquaint (or reacquaint) folks with @RegenPGC and our vision for using perennial groundcover in row crop fields for all kinds of interesting benefits.. This first video features Dr. Ken Moore and Roger Hintz, two members RegenPGC Team who have the most experience of anyone trying to manage and maintain yields when incorporating perennial ground cover into a row crop system –so, this video – https://lnkd.in/gbdgz9mQ is for you. (See the accompanying Field Notes at https://lnkd.in/gHQsGpXP)

We acknowledge that some of you may be unfamiliar with perennial groundcover and its potential for modern agriculture. Consequently, we have initiated a new series to educate (or reeducate) folks in the agriculture sector about RegenPGC and our vision for introducing perennial groundcover to the row crop landscape.

This video showcases Dr. Ken Moore and Roger Hintz, two individuals with extensive experience managing and maintaining yields when incorporating perennial ground cover into row crop systems. This video, accessible at https://youtu.be/MYQcSBZXVXQ, and you will find the accompanying Field Notes at https://iastate.box.com/s/fij94zkojl6kpaofkmepdk66cpzb0ij3.

Over the next several weeks, we will be dropping in more from this series into our blog. Stay tuned!

 

 

More honors and recognition for the RegenPGC Graduate Education Community

Our 18-member Graduate Education Community (https://www.regenpgc.org/theme-3-education/graduate-education-copy/) never stops impressing us with their dedication to good research and the RegenPGC vision.* But this month shows what an interesting and talented group we have.

Hallie Sandeen (University of Kentucky / Mentor Dr. Erin Haramoto) received a 1st place award at the University of Kentucky’s Integrated Plant & Soil Science Department Fall 2024 Symposium for her poster “Evaluation of Poacae Species and Suppression Application Methods for Permanent Groundcover in Corn.” Earlier this year, Hallie was recognized as the Weed Science Society of America’s 2025 Photographer of the Year! At the Society’s Annual Meeting in Vancouver.

We learned Graduate Student Jack Moran’s (Iowa State University / Mentors Drs. Susan Goggi & Ken Moore) interesting backstory of how he made it from Multyfarnham, Central Ireland, to Iowa State University. Jack’s Iowa State University ‘origin story’ was shared in an article by the ISU College of Agriculture and Life Sciences Office for Global Engagement. You can read “From Exchange Student to a Master’s Degree: a Global Journey to Iowa State University” at https://global.ag.iastate.edu/news/2025/exchange-student-masters-degree-global-journey-iowa-state-university

*Our vision is to create well-adapted PGC systems for a range of farm operations that require low labor inputs, provide significant ecosystem benefits, increase row crop resiliency, and have similar economic profiles as conventional row crop practices.