By Ricardo Costa and Paul Gross
Developing a termination method for cover crops is an integral part of the planning process to ensure there is no interference with your subsequent cash crop.
So you are planning on planting a cover crop? Did you know you also need to think about termination, regardless of how far off this will be happening? Keep in mind that when selecting a cover crops species to plant, you will have up to three termination options to choose from: winter kill, mechanical methods and herbicides.
The easiest termination method is winter kill. According to Michigan State University Extension field crop weeds specialists Christy Sprague and Erin Hill in their recently updated Cover Crop Termination Bulletin, the factors that determine if a cover crop will survive the winter or "winter kill" are related to the natural hardiness of the plant. Also, take into account its physiological capability to withstand cold temperatures, the weather and the stage of plant growth before freezing temperatures. Remember that winter kill doesn’t always work, so make sure to scout for survivors.
You can also terminate cover crops using mechanical methods such as moldboard plow and chisel plowing. If you are under a no-till system and are looking for strategies that won't disturb the soil, using a roller-crimper can be effective for terminating cereal rye and hairy vetch. Just remember that success is dependent on the growth stage of the cover crop. For cereal rye and hairy vetch, termination with a roller-crimper needs to happen when they reach the point of flowering.
The final termination method is the use of herbicides. If going this route, consider the following: growth stage of your cover crop, if the crop is actively growing, the species you have, your herbicides and adjuvants options, crop rotation restrictions, and the weather forecast.
In summary, make sure to get your cover crop terminated so you can get all the benefits of having cover crops, such as reductions in soil erosion, soil crusting and weed pressure, as well as improving your soil water holding capacity and increase in soil organic matter levels without competing with your primary cash crop.
Paul Gross, MSU Extension field crops educator, presents in the video below a very informative and easy-to-understand way about the various cover crop termination methods. You can also get more information about cover crop termination methods in Michigan by accessing the Cover Crop Termination Bulletin.Source : msu.edu