We need to figure out how to protect soil after soybean without hurting corn yield.

1. Use a farmer board to brainstorm ways to protect soil after soybean without hurting a following corn crop, with the
expectation that cover crops will be a key component.
2. Continue testing the 20 best ideas from the August 2019 brainstorm session in small plots on the University of
Missouri research farm to see how well they protect soil and how they affect yield of a following corn crop.
3. Feed the best performing systems from the research plots to the Missouri Strip Trial program for on-farm testing

1. Use of a farmer board to choose treatments for small-plot experiments. This collects the ideas from people who are thinking about the problem and who know which solutions could be practical and which could not.
2. Testing 20 approaches. Most cover crop experiments have used no more than 6 to 10 approaches.
3. Opening the door to a range of both cover crop species and management approaches (for the cover crop and for the following corn).
4. Evaluating soil protection level in June. May and June are our months with the greatest potential for erosion. The corn canopy is not yet protecting the soil during these months. Some people have told me that clover or vetch is the answer; others say that fall growth is nonexistent and spring growth is too slow to provide the needed protection by the time corn should be planted. We need to know both that corn will not be hurt and that soil will be protected at the most vulnerable time.

Updated April 27, 2021:
The objectives of this project are first to evaluate which cover crops can we plant after soybean that provide effective
soil protection without hurting the yield of a following corn crop. And secondly, to determine how best to manage the cover crop or the corn to make the system work best.

Results:

Objective 1: Which cover crops protect soil after soybean without hurting corn yield?

Winter oats worked best, among the species tested, to protect soil without hurting corn yield, giving a yield of 188 bu/acre. There may have been a small (4 bu, 38% probability) yield penalty but less than other cover species. Soil protection was excellent with winter oats. Annual ryegrass also gave excellent soil protection but caused by far the largest yield penalty of any species: 86 bushels. Corn was stunted early in the season following ryegrass.

Objective 2: How can we best manage the cover crop or the corn?

Planting soybean green into tall rye or wheat looked promising for soil protection with minimal corn yield loss (3 bu/ac, 39% probability). This relies on the rye/wheat residue to protect soil all the way through until the following corn crop canopies. Soil protection was good in January after soybean harvest; however, it deteriorated considerably by late March when erosion potential is higher.

The best ideas in the research plots will be added to the Missouri Strip Trial program for on-farm testing.

finding news ways to protect farmland topsoil and keep it in place.