The results are in. The 2024 Soybean Watch field was harvested Oct. 6. Subtract dry corners, and the field averaged 70 bushels per acre. Historically speaking, that is a more-than-respectable yield. Yet considering many soybean yields were above average this year and this field is irrigated, the yield fell short of expectations.

“One lesson to take from this field in 2024 is that it takes more than water to deliver very high, top yields,” says Steve Gauck, a regional agronomy manager for Beck’s, sponsor of Soybean Watch ’24. Gauck is based near Greensburg, Ind. “We tend to think that if we have irrigation, we should be able to harvest top yields each year. The reality is that other agronomic, weather and even soil-type factors play into the equation.”

Still, it was obvious that irrigation made a big difference in this field. “There is a reason why it is irrigated in the first place,” Gauck says. “About half the field is a soil type underlain with sand and gravel, starting just below 30 inches deep.”

That’s why dry corners underlain by gravel topped out at 50 bushels per acre. Irrigation was worth about 20 bushels per acre of extra soybean yield, he notes.

Yield-limiting factors

“Water is only one key to the puzzle,” Gauck says. “You still need to get the basics right. They include planting date, planting depth, variety, population, disease control and weed control.”

Related:Do you want 4-bean pods or bigger beans?

Here is a closer look at these basics, plus more:

Planting date. This field was planted May 12, still within the window where most data says top to near-top yields are possible. The cutoff is typically after May 15. This likely wasn’t a major factor, Gauck says.

Planting depth. Gauck prefers planting soybeans around 1.5 inches as a minimum depth, giving nodulation an edge with slightly cooler soils. That was the planting depth in this field.

Variety. Two varieties of two different genetic backgrounds were planted here. Tracking on the yield monitor, there was little to no difference by variety.

Population. The grower dropped 140,000 seeds per acre, and hula-hoop counts at V2 indicated around 100,000 or more plants per acre. This was likely not a factor, Gauck says.

Disease control. No fungicides were applied because the grower was concerned about dropping commodity prices by midsummer. However, very few disease issues were observed. “The field was very clean all summer and until harvest,” Gauck says.

Weed control. There were some weed escapes and a bit of volunteer corn, but everything was cleaned up with two postemergence passes. Weeds were minimal at harvest.

Soil type differences. Gauck believes this could be the kicker. A large, red, eroded hill runs across the width of the field. Soybeans were shorter there. The yield monitor dropped to 55 bushels per acre or lower on each pass.

“Soybeans didn’t achieve as much height there during the dry period in June, and that could be a factor,” Gauck says. Irrigation wasn’t used at the time because moisture was still adequate in most of the field.

“This deserves some follow-up work,” Gauck notes. “My suggestion would be testing for nematodes and soil fertility at the same time. There could be another explanation for why soybeans were shorter and less productive there.”

From the field:
Variability describes Upper Midwest yields, too

You know how your soybeans are yielding this year. What about soybean crops across the rest of the Midwest? How are they doing?

This week’s featured season wrap-up column is from South Dakota. Jerry Mathis, a Beck’s field agronomist, reports on how the soybean season unfolded in that region:

“With soybean harvest in full swing, yields have been all over the board. They are a pleasant surprise in some areas, but disappointing in other areas.

“Looking back at the growing season, we started off on the dry side in April. This allowed some growers to get an early start on planting. This dry pattern did not hold. Late April and early May rains kept most planters out of the field. Then, planting progressed from mid-May through early June. Areas with excessive rains and drowned-out areas planted into early July.

“Early June saw little rain and good growing temperatures to get plants started. Mid-June saw storms again, with growers receiving from 5 to 18 inches in a few days. Weed control became a challenge with excess rainfall. Waterhemp controlled early yielded to a flourish late. Add to this aphid pressure, which resulted in a lot of fields being sprayed. Some fields were sprayed more than once. Rainfall was very limited after June 21. Some areas received only about 3 inches for July, August and September combined.

“Fields that were planted early looked very good throughout the season, handling conditions well. Pod set starting in late June looked very good. July and August had some varying temps, with highs in the 90s and little rainfall. Late-planted beans and stress was not a good combination for pod set. Considering everything plants went through, they still looked good overall.

“Overall disease was not excessive. There are cases of charcoal rot, white mold and fusarium, which will impact yield. I would encourage anyone looking at seed for next year to pay attention to what is needed for a disease package by field. Look for a seed treatment program that enhances disease treatment.

“As harvest is happening, the real drought-stressed soils and waterlogged soils are being hit worst with yield losses. Some varieties are showing green stems with dry beans, causing a delay in harvest. We are hearing some disappointing yields, but also some record yields. Overall, I would say it’s a good year for yields. Considering late planting and environmental conditions, there will be areas where 50 bushels per acre will be an awesome yield. Planting early with good fertility has made a big difference in yields. 

“Fields planted early where the grower used a foliar fertilizer program appear to have some of the top yields. It’s not often I talk with growers who see over 100 bushels per acre on the yield monitor, let alone having some averages, so far, falling just under that milestone yield.”