Sustainability

Ground Work 2021: Planting Soybeans in Michigan

We are in full planting mode! We often have limited good days to plant our soybeans and corn, due to spring storms. That means when weather and field conditions allow, we are working as efficiently and quickly as possible. We are staying in close contact with our input suppliers to make sure we have the seed, fertilizer and herbicides we need when we need them, and calling our equipment supplier when we have problems with our equipment.

But like any spring, weather conditions have varied greatly, and we have to adapt to changing conditions. One example of our constant adaption is managing our cover crops. Because air temperatures were cool, the cover crop was not actively growing when we were ready to start planting. The herbicide we prefer to use to terminate the cover crop is much more effective if it is applied to an actively growing crop. We also prefer to terminate the cover crop before the crop emerges, but if timing and field conditions don’t cooperate, we can switch to a different herbicide and still terminate the cover crop without impacting our emerging seedlings.

The terminated cover crop adds organic matter on the soil surface, while their root systems that have been growing since last fall add additional organic matter under the soil and allow the soil to absorb water better. We have seen that our no-till and cover crop systems help our soils to handle heavy rainfalls fairly well. That’s a key benefit, especially with the spring storms that limit days we can plant.

We like to start planting when soil temperatures are about 10°C, or 50°F. And so, we started planting soybeans in mid-April. We planted our first fields into the green cover crop. We planted about 60 hectares, or 150 acres, and then we got a late spring storm that dropped about 10 cm, or 4 inches, of snow. Fortunately, soybeans can handle some cold temperatures, and the snow actually acted as an insulation blanket for the soil, protecting the germinating seedlings that were underground from freezing air temperatures for a night or two.

However, it quickly warmed up and the snow melted. This week we expect high temperatures above 21°C, or 70°F. As soon as our fields were dry enough to handle equipment without causing compaction, we got back to work in the fields. That included terminating cover crops both before and after planting, as well as planting more soybeans. We can plant about 40 hectares, or 100 acres, of soybeans in a good day. With good weather, minimal equipment problems and continued access to the inputs we need, we are finishing soybean planting this week.

In the last couple years, we have shifted to planting our soybeans first, because we have seen them handle unpredictable weather better and yield better when planted early. We typically plant maturity group 2.5 to 3 soybeans, and planting them early allows them to flower and fill pods in good growing conditions during the summer.

Then next week, the first week of May, we plan to start planting corn. We have enough equipment that we can plant both crops at the same time. The corn will take us a bit longer to plant, but we hope to finish planting it by the third week of May.

Planting is when the value of the precision technology we use really shows up. Both our soybean and corn planters can be programmed to vary the seed population being planted as they move across our fields. Based on our soil tests, we create maps to plant lower soybean populations where the soils are more fertile because the plants will grow more branches. We plant higher populations where the soils require it, like a hill with sandy soil in the middle of one of this year’s soybean fields. The planter technology interprets those maps and changes how close together seeds are planted based on that data. This efficient use of resources is one way we are becoming more sustainable.

Spring planting means that we are making lots of decisions as we adapt to the constantly changing conditions. Though weather and other factors may limit our management options, we intentionally try to choose what is best for our soil, our resources and our crop quality.

Laurie Isley

U.S. Soybean Farmer

Michigan

Laurie Isley is currently president of the Michigan Soybean Promotion Committee (MSPC).