Suggestions for managing flooded fields for next year’s crop

submitted by Sara Berges
Allamakee SWCD

One big question many farmers have as a result of the recent flooding is how to mitigate damage to crop fields and their soils. The floods likely left behind debris, scour holes, and sand deposits. If the crop was under water, it will likely need to be destroyed using a brush hog, tillage or other approved method. Contact a crop insurance provider with questions.

If fields were under water for a while, much of the beneficial soil biology may have been destroyed. One way to improve soil health would be to plant a cover crop. It is too late in the year to plant a winter-kill species, like oats, and have enough growth to provide much benefit. Instead, a winter-hardy species like cereal rye or winter wheat would help to develop soil structure through their fibrous root systems. They will also help to protect the soils from spring rains.

If the field was planted to corn this year, it would be advisable to avoid planting corn next year due to volunteer corn becoming a problem. If planting rye or other winter-hardy cover crop, soybeans may be planted into the growing cover crop to maximize the rye growth (organic matter) and root growth. The rye can be killed within one to two weeks of planting the soybeans.

The cover crop will also help protect from soil splash on the beans and reduce mold potential.

A rye cover crop could also be left to be harvested for grain. This would allow the field to rest from corn/soybean production for a year. After rye harvest, a cover crop could be planted in late July or early August to provide adequate growth for fall grazing options.

If unable to plant a cover crop this fall, consider planting oats or other small grain crop next year. With low corn and soybean prices, this may be a good time to try something different. There are many benefits to planting small grains, including reduced input costs, reduced pesticide use due to a disruption in pest cycles, reduced herbicide inputs, diversified farm income and labor, and improved soil health.

If red clover is planted with the small grain, or frost seeded under a fall-seeded small grain, it can provide a substantial amount of nitrogen for the following corn crop. Alternatively, it can be hayed or grazed after small grain harvest.