Indiana farmers considering corn stover as a new revenue stream now have fresh data to inform their decisions, thanks to early findings from a research partnership between Purdue University, FiberX, and the Indiana Corn Marketing Council.
Dr. Dan Quinn, Purdue Extension Corn Specialist, along with graduate research assistant Bruno Scheffer, recently published interim results from the ongoing study examining how corn stover harvesting affects soil health, nutrient levels, and long-term farm productivity.
The Numbers Behind the Stover
The research, conducted at two diverse Indiana locations—Purdue’s Agronomy Center for Research and Education (ACRE) in West Lafayette and the Southeast Purdue Agricultural Center (SEPAC) in Butlerville—revealed some straightforward relationships that farmers can use for planning.
The headline finding confirms what earlier research suggested: there’s roughly a 1-to-1 ratio between pounds of grain produced and pounds of dry stover left in the field. At the ACRE location, corn yields ranging from 280 to 300 bushels per acre corresponded to approximately 7 tons of dry stover per acre.
“As corn yields continue climbing in Indiana, the amount of stover we’re producing continues to climb right alongside it,” explains Quinn. “With Indiana producing roughly 30 million tons of corn stover in 2024 alone, understanding how to manage this resource responsibly is increasingly important.” Interestingly, Quinn’s team found that short-stature corn varieties, which are being planted to provide resistance to high winds and increase planting density, produces comparable amounts of stover per acre as tall-stature varieties.
Understanding What Leaves the Field
One critical aspect of the research focuses on nutrient removal—specifically, what farmers lose when stover is baled and removed rather than left to decompose naturally.
The study examined nutrient composition across different hybrid types, including comparisons between traditional full-stature hybrids and newer short-stature varieties. The findings showed remarkable consistency: both hybrid types exhibited similar concentrations of nitrogen, phosphorus, and sulfur. Potassium levels showed slight variations, running marginally higher in short-stature hybrids.
On average, stover nutrient concentrations measured:
- Nitrogen: 0.81-0.82%
- Phosphorus: 0.12%
- Potassium: 0.72-0.79%
- Sulfur: 0.06%
These percentages translate to real costs. Every ton of stover contains approximately 3.6 pounds of P₂O₅ and 20 pounds of K₂O. For a field producing 4 tons of dry stover per acre, removing 60% through baling means taking out roughly 9 pounds of P₂O₅ and 50 pounds of K₂O—nutrients that would otherwise cycle back into the soil for the next crop.
The Bigger Picture: Balancing Opportunity with Stewardship
For Indiana farmers, the emergence of markets for corn stover—from companies like FiberX producing biocomposite plastics to other bioenergy and bioproduct applications—represents genuine economic opportunity. But the research underscores that this opportunity comes with important considerations.
“Stover isn’t just leftover plant matter,” Quinn notes in the research findings. “It contains essential macro and micronutrients, protects against erosion, helps retain moisture, builds soil organic matter, and contributes to long-term carbon storage.”
The research emphasizes that removing too much stover can deplete essential nutrients, reduce soil fertility and quality, and potentially force increased dependence on synthetic fertilizers. It’s a balance that requires careful management and planning. Quinn suggests that removal rates of up to 50% appear to protect soil health.
What Makes This Research Different
This isn’t the first time researchers have looked at corn stover harvesting. What makes this project unique is its timing and scope. As corn genetics evolve and yields continue their upward trajectory, old assumptions needed fresh examination.
“As corn grain yields continue to increase and as corn genetics and physiological traits continue to change, it is important to reassess dry stover totals, quality and the impacts of stover removal in current production systems,” the researchers explain.
The study is also notably collaborative, bringing together farmers, agronomists, nutrient suppliers, water quality experts, and industry representatives through a stakeholder advisory council. This ensures the research addresses real-world farming conditions and concerns.
Looking Ahead
These findings represent only the first chapter of a multi-year research project. The team expanded the research in 2025 and hopes to continue the program, building a more complete understanding of long-term soil impacts under different stover removal scenarios. Future phases will also examine how cover crops can be integrated with stover harvesting to maintain optimal field conditions.
The study also identified an intriguing finding that it appears that excessive residual corn stover may reduce soybean yield in subsequent years, by as much as 10%, when rotating crops. Since Indiana farmers generally rotate corn and beans this finding has important implications.
“This research is ongoing and will be expanded and repeated in 2025 and beyond to refine results and assess long-term soil impacts,” the team notes.
For FiberX, this research is foundational to our commitment to renewable stover sourcing. We’re not interested in solutions that trade short-term gains for long-term soil health. The goal is developing practices that work for farmers, work for Indiana agriculture, and work for the long haul.
“This isn’t just about research—it’s about building a framework for the future of agricultural residue utilization that benefits everyone involved,” says Wade Lange, FiberX’s Chief Commercial Officer.
The Path Forward
As Indiana positions itself at the forefront of the growing biomass industry, data like these interim findings will be crucial for developing science-based best practices. Farmers need reliable information to make informed decisions about whether and how much stover to harvest.
The research makes clear that farmers must balance the potential for additional revenue against the need to maintain soil fertility, health, and long-term productivity. It’s not an either-or proposition—it’s about finding the right approach for each field, each farm, and each farming operation.
We’ll continue sharing updates as this research progresses. In the meantime, the early data provides valuable benchmarks for understanding stover production levels and nutrient implications across Indiana’s diverse growing regions.
This research is funded by the Indiana Corn Marketing Council in collaboration with Purdue University and FiberX. For more information about the research project, visit FiberX’s research announcement.
Key Takeaways:
- Indiana corn fields producing 280-300 bushel yields generate approximately 7 tons of dry stover per acre
- A 1:1 ratio exists between grain pounds and dry stover pounds produced
- Every ton of removed stover takes about 3.6 pounds of P₂O₅ and 20 pounds of K₂O from the field
- Both full-stature and short-stature hybrids show similar nutrient profiles and produce similar amounts of stover=
- Research will continue through 2025 and beyond to assess long-term impacts
