A lot of soybeans are no-till in the U.S. and across the Corn Belt. However, in regions with flat, black dirt some growers are still utilizing conventional tillage to warm and dry the soil more quickly in the spring, before planting soybeans. Could these growers practice no-till on those soybean fields? Probably. But to do that will require tighter management and full utilization of the tools available to make it work—which is true for all no-till situations.
Agronomist Ed Winkle wrote a booklet, “Growing High Yield No-Till Soybeans,” and summarized his tips for successful no-tilling. The booklet was published in 2015 by No-Till Farmer. Eighteen tips with excerpts are listed below. It’s interesting that these tips, while a bit dated, apply to all soybeans, whether planted under tilled or no-tilled conditions, or as a full season crop or double-crop.
- Soil: “Soybeans grow best under good soil conditions, such as a highly fertile, medium textured loam soil, even though profitable soybeans can be produced on a wide range of soil types.”
- Rotation: “Soybeans fit well in many crop rotations. Since soybeans are legumes, they are usually rotated with grass crops. However, some no-till growers have had good success growing continuous soybeans.”
- Seed Selection: “Variety selection should be based on maturity, yield, lodging and disease reaction.”
- Seed Quality: “Selection and use of high-quality seed, as well as matching the disease package genetics to your location, are basic keys to optimizing soybean yields.”
- Seed Treatment: “Treating soybean seed under many conditions with a fungicide, or a fungicide plus an insecticide, often does not increase yields when high-quality seed is planted. However, seed treatment definitely is a benefit for conditions where seed is damaged by disease, frost, excessive seedcoat breakage, age or in fields where soybeans are planted 2 or more years in a row.”
- Inoculation: “Soybeans that are properly nodulated have the ability to fix nitrogen from the atmosphere. Nodulation requires the inoculation of the seed prior to planting with certain species of rhizobium bacteria. The inoculation of seed for planting in fields having a prior soybean history is suggested with the new strains of bacteria.”
- Seedbed: “Preparation of a firm, uniform seedbed is important for optimum stand establishment. Like other legumes, soybeans have difficulty emerging through compacted layers and surface crusts.”
- Fertilizing: “Soybeans yield best in highly fertile soils and make good use of carryover fertilizer. If a soil test or response in other crops indicates low phosphate availability, an at-planting band application of 10 to 30 pounds per acre of phosphate may be beneficial.”
- Seeding: “As with most crops, soybeans are susceptible to frost and prolonged exposure to near freezing conditions in both spring and fall. Plant no-till soybeans after the soil has reached 50°F and air temperatures are favorable. Seeding in cool, wet conditions with the right no-till rig is preferable to planting in hard ground. Emergence will be delayed with hard ground and the soybean roots don’t have the chance to develop properly.”
- Seeding Rates: “An ending plant population of 120,000 to 125,000 plants per acre is desirable regardless of which row spacing is used. However, top yields have been harvested with anywhere from 80,000 to 120,000 plants per acre.”
- Rolling: “The primary purpose of rolling soybean ground is to push rocks down into the soil surface and level the soil, so a lower cutter bar height can be used at harvest.” More recent research indicates that rolling between V1 and V3 can stimulate branching and increase pod set.
- Weed Control: “Control of early weeds is among the most critical components of a profitable soybean production system. Weed control during the first 2 to 4 weeks of the growing season is essential to maximize yield. It’s much easier to accomplish this with no-till than with more intensive tillage systems.”
- Diseases: “Major concerns with soybeans following soybeans are disease problems, weed species shifts and an increased potential for soil erosion. Three of the most worrisome pest problems are white mold, brown stem rot and soybean cyst nematodes (SCN). These concerns are often greater with soybeans grown after soybeans.”
- Soybean Cyst Nematode: Probably the number one pest in soybeans and symptoms are often unnoticed. “A soil test is recommended for egg counts of the nematode, which feeds on host plants. The lab will recommend that you consider abandoning soybean planting (10,000 eggs per 100 cc of soil) or select resistant varieties for reduced populations.”
- Soybean Aphids: “Treatment to manage soybean aphids is recommended at early flowering (R1 to R2) when aphids are abundant on most plants (spray when aphids number 25 or more per sampled leaf). University of Wisconsin research trials found a population of 200 aphids per plant during the susceptible growth stages (R2 to R4) resulted in a yield loss of about 6 bushels per acre.”
- Scouting: “Doing your own crop scouting or hiring a consultant to do this task is extremely valuable in making sure your soybean plan results in top yields. Besides taking steps to protect this year’s crop, scouting is also valuable in planning next year’s crop.”
- Roots: “Make sure that you dig up some bean plants during the season and analyze them. Study the roots, nodules and soil aggregation compared with other fields in the area. Don’t be afraid to show these plants to others and get another opinion.”
- Harvesting: “Harvest when mature plants contain 14% moisture. Harvest may be started at 17% to 18% when air drying is available. However, harvest as much of the crop as possible above 12% moisture to avoid cracking and splitting (and yield loss).”
Ed Winkle owned HyMark Consulting, and was an agronomist and no-till farmer from Martinsville, Ohio. Winkle authored the 16-page report for No-Till Farmer entitled, “Growing High-Profit No-Till Soybeans.”
He gained popularity advising and speaking on no-till soybeans. He passed away in 2015. Winkle and I used to trade ideas and solutions for pushing higher yields in no-till soybeans.
Soybean agronomist Daniel Davidson, Ph.D. posts blogs on agronomy-related topics. Feel free to contact him at firstname.lastname@example.org or ring him at 402-649-5919.