Over the last four years, it has become a lot more common for producers to grow a “cover crop” after winter or spring wheat has been harvested or on acres that have been deemed “prevent plant” due to wet conditions. A cover crop is simply defined as any crop that is planted between periods of regular crop production.
The goal of planting a cover crop can vary considerably from producer to producer. For some it can provide fall grazing for livestock, for others it can suck up extra moisture in “prevent plant” acres and help reduce potential problems from salinity. Whatever the goal or goals of growing a cover crop; the benefits can be numerous. Cover crops can improve soil quality, scavenge and recycle nutrients, fix atmospheric N, break soil hardpans, reduce compaction and erosion, increase soil biological diversity, suppress weeds, decrease runoff and provide wildlife habitat.
What cover crops should I plant? The list of plants suitable for cover crop usage is long. This can make the decision regarding what cover crops to plant overwhelming. A good starting point is for a producer to first identify what the goal of their cover crop is going to be? If there is more than one goal, narrowing the goals to one or two primary goals and perhaps a few secondary goals will be helpful. This will simplify the search for the best cover crop species.
Cover crops can be divided into four types; warm season broadleaves, warm season grasses, cool season grasses and cool season broadleaves. Research performed in South Dakota and other areas has shown that the benefits of a cover crop are maximized when they consist of a mix of types and species. An extensive list of cover crops, their specific characteristics including what category they fall into is listed at the following web address: ftp://ftp-fc.sc.egov.usda.gov/SD/www/Technical/Agronomy/Cover_Crops/Cover%20Crop%20Characteristics_031910.pdf
This information will be very beneficial to anyone looking for a tailor made cover crop mixture.
Once a cover crop mix has been designed and prior to seed purchase, there are some questions that growers can ask themselves to ensure a smoother experience with cover crops. For instance;
- Will the selected cover crop species act as a host in pest cycles in adjacent crops, as well as for the next crop in the rotation?
- How will I seed the cover crop?
- What were the previous crop herbicides and will they affect the cover crop(s) I want to plant?
- What will soil temperature and moisture conditions be like?
- How vigorous will other crops (or pests) be?
- What weather extremes and field traffic must it tolerate?
- Will it winterkill in my area?
- Should it winterkill, to meet my goals?
- What kind of regrowth can I expect?