Carl Joern

Corn yield gains in the U.S. are no longer tied to higher plant densities. 🌽 Recent genetic progress is driven by increased yield per plant—not improved crowding tolerance—highlighting a clear decoupling between yield and plant density. Full article: doi.org/10.1016/j.fcr.…

Type this prompt into your favorite LLMs and compare the responses to ISU PM-1688: "I have a soil test from Iowa that reports a phosphorus level of 23 ppm using the Mehlich 3 ICP extraction method. What would be a recommended amount of phosphorus for 240 bu/ac corn?"

Met with growers who partnered on ‘25 on-farm trials. Good conversation around real-world results. This year: corn population, Peking rotation, product timing & drone work. NW IN/NE IL growers interested in partnering, reach out. What agronomy questions should we test next?

EPA finalized 2 more seasons of OTT dicamba on DT soybeans & cotton — with tighter rules. Key changes: • Fewer approved products • Lower rates • Temp cutoffs (restricted ≥85°, no use ≥95°) • Higher VRA rates Clearer rules. Less flexibility. brownfieldagnews.com/news/epa-final…

Agronomy Lessons from 2025 Excessively Dry Soybeans at Harvest has cost growers serious $$ past few seasons. Getting soybeans out of the field near 13% has been a real struggle the past few seasons. Earlier planting has often increased yield potential, unfortunately sometimes the beans are maturing in early to mid September w/warmer days that lowers moisture quickly. Green stems have also hindered the ability to harvest when grain moisture is optimal.. Spreading maturity out more has helped... but not a solve all. Hoping to try some seeding rate & fungicide trials this season to try to find a solution. Will take any thoughts..

Agronomy Lessons from 2025 Residue in the seed trench causes frequent delayed emergence and thus runt plants with small or no ear. In evaluating stands over the years I have found it accounts for 40-60% of runt plants. In tillage systems it is nearly impossible to avoid. The more residue that can be left on the surface and moved to the side with planter attachments the better. Of course this can cause cooler & wetter soils. Residue free seed trench IMHO is maybe the largest benefit of strip tillage... right up there with banding nutrients.

Agronomy Lessons from 2025 Horizontal tillage in the spring can create serious density layers. A leaf blower can expose what may look like a great job of tillage on the surface, & very uneven tillage floor. Shallow tillage tools like high speed discs & vertical tillage units can create very uneven tillage floors. Recommend last tillage pass is in the same direction as planting pass so row units do not have to ride over the density layers, creating uneven planting depths and poor ride quality. Resulting in uneven emergence. Be sure to check out your tillage floor this spring! Photos from Ben Covington with ISU Ag & Biosystems Engineering Department.

Agronomy Lessons from 2025 Manure continues to perform as the "ultimate" fertilizer source. Results from the stalk nitrate project in the geography I cover revealed fields that had manure as their main nitrogen source performed exceptionally well. Supplemental N of 40-60# generally maximizes return to N investment. Essential to have applications after soil temps get below 50 degrees (ideally 45) and complete incorporation. Manure value chart I worked thru w/customer yesterday shows value of their manure was $100+/1000 gallons, without giving any credit to micro nutrients and biology enhancements. Working with neighbors on "buying" manure like commercial fertilizer likely has major benefits for both parties. Contact your local Pioneer Sales Representative to help calculate your manure value!

Agronomy Lessons from 2025 Too much of a good thing? With livestock operations being highly concentrated in some areas, repeated manure applications can result in too much of a good thing. Items to watch are: 1) Phosphorous levels 2) %NA in your base saturation and excess salts on your soil tests. 3) P/Zn ratio 4) High early N availability resulting large amounts of vegetative growth 5) Phosphorous risk for movement into surface waters. Visit with your local Pioneer sales rep to review manure plans & cost/benefit of transporting manure to other farms.

Agronomy Lessons from 2025 Cold soils in spring are often times not as "fit" as they appear. A couple very warm windy days makes the top 1" very dry, however the cold soil below has not dried out enough for field operations. Famous saying of "the dust was rolling" without inspection 2-6" down caused many issues again this spring. NH3 burn was extremely common on very early applications and a lot of poor seed furrows/crusting/sidewall compaction on mid April plant dates. Be sure to get out and dig!

Good conversation with @NoTillFarmr on tar spot and what to watch heading into 2026. Big takeaway: if weather lines up, it can show up fast. Early scouting still matters. Give yourself the best start with @PioneerSeeds tolerant genetics no-tillfarmer.com/articles/14921…

Southern rust caught a lot of us off guard in 2025. Joined Agriscience Explained to talk why it showed up so strong, what we learned, and where future disease protection is headed. If it hit your corn, this one’s worth a listen. 👇 podcasts.apple.com/us/podcast/sou… @corteva @PioneerSeeds

When yield ceilings are pushed, @PioneerSeeds shows up.

🌽 Pioneer hybrids earning national hardware: • P18216PCUE — highest yield overall • P13777PCE / V — multiple Top-3 finishes • P1136AM — No-Till Non-Irrigated winner • P1464VYHR — multi-system podiums • P1742Q, P17677, P1572AM — national Top-3

🏆 Pioneer Stacks Up with the Best — and Takes the Top Spot 🌽 In the 2025 NCGA National Corn Yield Contest, Pioneer® hybrids went head-to-head with every major brand and delivered wins, podiums, and the highest yield in the nation.

Dad: “Makes you appreciate it when you write the check…” Son: “…a little bit 😂” Heard this on a production plant tour with a local farming family and our Tipton @PioneerSeeds team. Always a good reminder of the work that goes into delivering high-quality seed every year.

On Farm Testing 2026... If you have soybeans in your rotation in fields relatively often, and yields are stagnant, Soybean Cyst Nematode (SCN) could be what's holding your yields back. Soil testing can reveal this hidden pest that can take 5-10 bu/ac with no above ground symptomology. In many areas the PI 88788 source of resistance has become ineffective to prevent yield loss and/or keep populations in check. Peking source SCN resistance in Z Series soybeans has proven in field trials to protect yield AND reduce populations. Talk to your local Pioneer Sales Rep on soil sampling procedures & Z Series varieties w/Peking that fit your acres!

From genomics to precision ag, @PioneerSeeds has kept pushing what’s possible—earlier trait integration, split-planter research, PROBOX seed handling, and industry-leading seed quality. A century in, innovation is still the habit.