Roy Pfaltzgraff has spent many years analyzing various aspects of his no-till operation, including row spacing, soil health and the seed he uses.

The fourth-generation, 2,000-acre farm in northeastern Colorado, which he farms in partnership with his father, is a combination research farm and education center that produces sustainably grown farm-to-table products.

When he’s not in the field, Pfaltzgraff works to create a supportive and collaborative community where fellow producers are encouraged to grow and succeed. Through his on-farm experiments, he inspires them to challenge the status quo and to question every aspect of their operations.

Recently, after having a discussion with Hickory, N.C. no-tiler Russ Hedrick, Pfaltzgraff began to question his program for treating seed, and he carried out an informal experiment where he applied a sugar-based seed treatment and 10 pounds of urea starter to peas.

“Does nitrogen make a difference?” Pfaltzgraff asks, reflecting on the experiment. “It makes a difference. Does sugar make a difference? It looks like sugar makes a difference. My sugar cost per acre that year was 16 cents. If it’s wrong, it’s the cheapest mistake I made. If it’s right, it’s guaranteed to be the best ROI you will ever have on input. Peas were $15 a bushel. That’s a good return.”

Early Corn Experiments

Further consideration led Pfaltzgraff to question whether his seed, treated with fungicides to prevent rot, might be harming the soil microbiota he was diligently attempting to colonize. He decided to reach out to some contacts.

Pfaltzgraff reflects on some frustrating moments at the start. “I wanted untreated seed. They said, ‘No,’ we can’t do that. It drives me nuts. You buy a bag of seed and you open it up and it’s not a natural color. It’s blue, or purple, or red. This way you have optimum conditions. That plant can survive any soil conditions. I say, ‘Do you have a seed treatment for hot and dry? I don’t have a problem with cold and wet. I have a problem with hot and dry.’”

Eventually, Pfaltzgraff’s persistence paid off and he was able to purchase untreated seed. “My corn seed shows up in a tote, now,” he chuckles. “That way you can’t return it. And, it’s funny when you load that seed into the drill, it doesn’t look right. It looks like corn. It’s not red or blue or whatever color they’re putting on your seed.”

In 2022, Pfaltzgraff grew 80 acres of treated seed and 80 acres of untreated. But with only 4.5 inches of rain that season, the crops failed. Notably, the untreated corn lived 3 weeks longer than the treated corn and, in 2023, Pfaltzgraff found volunteer corn in the untreated plot. “I got volunteer corn, on 4.5 inches of rain,” Pfaltzgraff says. No volunteer corn was observed in the plot that had received treated seed.

Replicated Plots

Intrigued, Pfaltzgraff ordered more corn seed and set up test plots, 3 replications of 4 acres each. He reached out to several suppliers and offered to test any commercial treatments they were willing to provide.

He settled on 6 different treatments: a standard commercial seed treatment, compost liqueur, 8 strains of fungal spores (Mycormax), a micronutrient for root elongation (by Amway), a biological and micronutrient combination, and untreated.

All non-commercial treatments were treated with an organic biological for wireworm and all plots were seeded on the same day.

From left to right, these plants were treated with standard commercial seed treatment, compost liqueur, 8 strains of fungal spores (Mycormax), micro-nutrient for root elongation (by Amway), a biological and micro-nutrient combination, and untreated. The mycorrhizal pack exhibited the best overall results. Note the untreated plant developed a more robust root network than the commercially treated one.

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Upon reviewing initial root development, Pfaltzgraff says he could see the difference, “straight out of the gate.” The worst was the standard seed treatment, which had very bare roots compared to a particularly fibrous root system with the mycorrhizal pack. “I have never seen a root system develop like that. It is crazy how that stuff put rhizosheath on,” he says.

What effect, if any, did the treatments have on yield? In the end, all of the test plots demonstrated similar productivity. Pfaltzgraff had yield potentials up to 200 bushels per acre and the difference between the highest and lowest test plots was 12 bushels. “Not 12 bushels per acre, 12 bushels,” Pfaltzgraff says. “Well within the standard of error that you would introduce on something like that.”

Curious about the less tangible impacts of the treatments, Pfaltzgraff reached out to the lab. “I’m like, there’s got to still be a story there, there’s got to be more to it.” Pfaltzgraff ran diagnostics on weight, moisture, and protein to better understand the effects.

Lab results indicated that plants grown from commercially treated corn seed dried out the quickest, exhausting their water supply first due to the limitations of their underdeveloped root systems. The mycorrhizal pack had higher water retention and lower protein content, indicating less stress from water scarcity.

If moisture had not been a limiting factor, Pfaltzgraff believes the mycorrhizal-treated plants would have outperformed the others – which he says is proof that seed treatments are “no longer relevant where moisture is a limiting factor.”

The graph presents laboratory findings from Pfaltzgraff’s corn trials. While the plots all yielded similarly, the standard commercial treatment corn showed a reduced water-holding capacity and higher protein content. The mycorrhizal pack showed more moisture retention and lower protein levels, indicating less stress from water scarcity.

What Works for You?

Pressure is a constant companion for farmers and Pfaltzgraff believes large corporations often pressure consumers into using their products, even when they aren’t necessary.

Within a community, traditional ideas can be deeply ingrained, and growers are often expected to follow established methods. 

Pressure exists within families, as well. Pfaltzgraff recalls a conversation with a neighbor who managed the research farm at Colorado State University. Pfaltzgraff inquired as to why his neighbor didn’t have a stripper head.

“His answer,” Pfaltzgraff recalls, “was, ‘I’d like to have a stripper head, I think there are a lot of benefits, but my Dad thinks there’s just too much header loss, so I’m going to wait until he’s gone before I get one.’”

As no-tillers evaluate their operation, goals should be front and center in their minds. “Are the products I’m using aligned with those objectives? Pfaltzgraff says. “You always hear, ‘I bought this biological and it worked great for me, and somebody else tried it and it didn’t do a thing.’ Well, it’s because, in each circumstance, the soil’s different. You’ve got to figure out what works for you and what will ultimately return the best.”