High-Yield Soybean Production Insights
Several Practices Add Up to Yield Gains
Combination of Factors
- I think achieving higher soybean yields comes down to a combination of things. No one thing jumps out as the only way to increase production. We have a lot yet to learn about increasing soybean yields, but we’re on the right track.
- Good organic matter levels and nutrients are critical to raising corn or soybeans. I apply plenty of nutrients for corn, and that helps when we switch the field to soybeans. We’re caring for the soil and not losing it to erosion.
- The best yields came when we applied glyphosate late. We didn’t see much weed pressure. Applying glyphosate and nitrogen late produced top yields for us.
- We grow corn for 3 consecutive years on a lot of our acres before we rotate to soybeans. Planting soybean after 3 years of corn helps break the disease cycle.
- Early planting helps. Planting in late April or early May might be ideal for both corn and soybeans. In the past, we didn’t think about planting soybeans until the end of May.
- Genetics: We have better soybean genetics to work with today.
- Seed treatments: They help establish better stands and protect the seed as it emerges.
- A fungicide-insecticide combination.
Fertility Fuels the High-Yield Soybean Factory
- Fertility is critical. In 2013, I switched to soybeans after I’d intended to plant corn. The fertilizer for corn was already blended. So we mixed micronutrients and used a half rate on the soybeans in our fields, which are center-pivot irrigation. Yields were fantastic. In 1 strip with additional nitrogen, we made 90 bushels per acre compared to 60 in the next strip that didn’t get additional nitrogen. It convinced me fertility is critical for higher soybean yields.
- To get 100-bushel-per-acre soybeans, you need 110 lbs. of available phosphorus per acre. You also need adequate nitrogen. When we get residue to break down and provide the right soil conditions, our soybean nodulation is through the roof. In 2014, we made 99.2 bushels per acre with only 2,300 Growing Degree Units. I think one of the factors was that we fertigated late with nitrogen.
- Some of our soybeans are dryland, and we’ve started fertilizing those acres, too. We got 74 bushels per acre by spending $40 per acre on fertility, compared to 38 bushels per acre where we didn’t add nutrients. That’s a very good return on investment.
- I add a full rate of a nitrogen stabilizer to provide a late-season, slowly released nitrogen source. Otherwise, soybean nodules can die off. Supplemental nitrogen lowers the carbon-to-nitrogen ratio in crop residue from the previous year’s. That speeds the breakdown of those materials and releases nutrients.
- We have great genetics now, so we need to manage soybeans more like we manage corn to get closer to a variety’s yield potential.
- I think it’s important to keep soybeans relatively dry. I plant in twin rows on ridges. Plants are able to pull nitrogen from the soil and the air. It takes energy to produce nodules, so when you can help free some of that energy, it’s available for grain fill. You’re trying to balance nutrient use for nitrogen fixation and for yield.
- Using a corn-corn-soy rotation helps break soybean disease cycles. I’m actually making more money off soybeans than corn, so it’s tempting to adopt a strict corn-soy rotation. But that may curb soybean yields a bit.
- It’s important to get the crop off to a good start. If you trip at the starting gate, you probably won’t win the marathon. Planting early seems to help. Last year, we actually had snow on beans we planted early, but we still got 99.2 bushels per acre.
- I want the soil temperature to be at least 55 degrees (F) before planting. If it gets cold after that, seed treatments can help. We had 90% stands with seed treatments, compared to 60% stands without. Uniformity was also much better.
- Irrigation management is something we’re working on. I hold back on water early in the year to ensure soybeans develop deeper roots. Deeper roots help standability. I think a moderate canopy rather than a lush canopy helps lower nodes fill pods better. It also may prevent some diseases that favor damp conditions from developing – sudden death syndrome is an example.
- Timely fungicide use.
- Weed control.
- Avoid injury from spray drift and residue from the previous year’s crop.
- Soil conditions: You need good soil conditions for high yields. You’re building a crop factory, and you need to provide that factory with the materials it needs to produce crops. Feeding it helps get you more of the potential yield of each soybean variety.
Early Planting Contributes to Higher Soybean Yields
- Planting earlier has made more of a difference than I thought it would. We plant soybean in early May. I see it as a key to increasing yields.
- I plant 170,000 seeds per acre with a goal of stands of 155,000 plants per acre.
- We’re mostly irrigated with center pivots. We’ve had success adding nitrogen and key micronutrients, but results can vary. Last year, I got a yield of 89 bushels per acre with a Pioneer® brand variety on land with no added nitrogen.
- We’re using grid sampling and applying fertilizer at variable rates. We may put 200 to 250 lbs. of phosphate per acre on areas that need it and nothing on other areas that don’t show a need. We may end up spending about the same amount of money, but we’re getting higher yields by targeting our nutrient applications.
- Planting 2 years of corn between soybean crops helps soybean yields. We generally follow a corn-corn-soy rotation. That extra year helps break soybean disease cycles.
- We feel we can gain 2 to 3 bushels per acre by harvesting at 12% to 13% when the beans are just slightly below what is recommended as optimal moisture.
- Seed treatments. We use seed treatments and herbicides to control early weeds and get early-planted soybeans off to the best start possible. Later in the season, we apply aerial treatments of fungicide and insecticide as needed.
- Weed control.
All decisions regarding fertilizer and weed, disease and insect control, irrigation scheduling and grid sampling to help maintain soil balance are made in consultation with and under the advice of Andy Runyun, Servi-Tech.