This fall has provided some great weather to harvest soybeans. As I write this article, combines are cutting beans and semitrailers are hauling the crop to the farmers’ bins or the nearest grain handling facility.
All of this is well and good, but what is left in the field once the equipment pulls out? Not a whole lot, thanks to more modern equipment and precision type farming.
Drive by any recently harvested soybean field and it would be tough to find much residue to hold soil in place for the winter, let alone keep the soil biology going through the winter months.
Water conservation, soil health, soil conservation, nutrient scavenging and carbon sequestering are not new ideas to the agricultural world. However, until just recently, these philosophies seem to have been collecting dust on a shelf.
In fact, I recently found a letter from a previous board chairman that read “Water quality is the buzz-word of the 90s and we fully intend to do our part to protect the water resources in Columbiana County and maintain the excellent public image of farmers as conservationists”. The letter was dated Nov. 15, 1989; that is 28 years to improve on these concepts.
Yet, I constantly hear, “Cover crops might work for Ol’ Zippy Dooda, but they won’t work on my farm”.
And then the cropland lays bare for the winter… I could understand the resistance to seeding a crop after soybeans are harvested if our only method was to no-till drill the seed in or if there was only one type of crop to plant, but that is not the case.
Farmers have become very creative with ways to apply seed to their crop fields. However, the growing season is getting too short to try some of the tactics.
Aerial seeding and precision row crop planter seeding are methods that need to take place while the cash crop is still standing in the field. This winter would be an excellent time to research these methods for next year’s cover crop seeding.
One planting method that could take place now would be to mix your cover crop seed with your slurry manure and apply it to your fields. The method ensures rapid growth of the cover crop and can be accomplished with one pass.
Another planting method is broadcasting; whether you shotgun the seed on after you harvest or do some light tillage is up to you. Either method will work and will give you some green growing in the field for the winter.
(You can grow oats/rye/wheat on concrete if you get a little moisture for goodness sake, so broadcasting will work.)
Farmers should increase their seeding rate 10-25 percent more than drilled rates to achieve a desirable stand.
What to Plant
The only other decision to make is what type of crop to plant. That decision needs to be based on the goals you have for the cover crop.
A call to a local agronomist, seed salesman or even your SWCD office may help you decide what to plant.
Here is a synopsis of objectives that cover crops can accomplish:
- Nitrogen producers: Legume cover crops can fix atmospheric nitrogen into forms that are available for the next cash crop.
- Nitrogen scavengers: The growing roots of these plants take up residual soil nitrate from fertilizer and soil organic matter mineralization, reducing the amount of nitrate that leaches out of the soil.
- Soil builders, subsoilers and topsoil looseners: These are the plants that help build soil organic matter and sequester carbon by adding their roots to the soil. The plants also provide additional food for soil fauna such as earthworms.
- Erosion preventer and lasting residue: The classic use of cover crops to protect against both water and wind erosion. A plant's live roots also help hold soil and reduce erosion
- Weed fighter: Certain cover crops are noted for their ability to suppress weeds which may be due to competition, shading or allelopathy.
- Grazing and forage value: Appropriate cover crop species selection and proper planting time can provide livestock producers extra forage that may be grazed by the livestock or manually harvested and stored for winter feed.
Keeping the soil covered and active, with a living root zone more months out of the year, leads to long-term soil improvements, productivity, and profitability.
So as you are sitting in the combine cutting beans or trucking loads of the crop to the nearest storage facility, be thinking about how you can make those fields green again.