
With the abundance of moisture most of the state has received in the last few weeks planting a cover crop after wheat harvest may be a viable option.
A cover crop can help suppress herbicide resistant weeds, reduce evaporation, provide good quality forage for livestock and provide many other soil health benefits. Here are a few things to consider if you are thinking about planting a cover crop:
- Have a goal in mind. Think about what you are trying to accomplish. Do want to use it for livestock grazing? Is there a compaction layer that you want to break up? Do you want to increase the ground cover because of short and thin wheat stubble? Use a seed mix that meets your goals. Don’t plant a cover crop just to plant one.
- Does planting a cover crop make economic sense? What is going to be the potential economic return, both short and long term, in comparison to not planting one? Figure all your costs, including seed, planting, any herbicide applications prior to planting, termination costs and so on. Then compare that to what economic gain or value you may have from less herbicide operations, providing livestock forage, capturing more rainfall other benefits. Try to keep seed cost reasonable at less than $20.00 per acre.
- Herbicides used in the wheat also need to be considered. Many popular wheat herbicides have long plant back restrictions and are persistent and effective the soil for long periods of time. Many of these herbicides may prevent some cover crop species from coming up. Make sure to check the herbicide label and if in doubt ask you’re your crop advisor or pesticide vendor.
- One of the purposes of planting a cover crop after wheat harvest is to reduce evaporation, improve water infiltration and increase the water holding capacity of the soil. But realize upfront that cover crops do use moisture, just like any green growing plant. Depending on the amount of rainfall during the season they may use more then what they save. This could have a negative effect on the next cash crop yield. If the growing season becomes hot and dry terminating the cover crop early may be a consideration. This is especially true as we move south and west across the state.
- Always plant in a weed free seed environment. Cover crops can be very effective in suppressing difficult to control weeds, but not if they are already present when the cover crop is being planted.
- For most of the state the recommendation is to plant the cover crop as soon after harvest as possible, preferably right behind the combine. This allows full advantage of the moisture and growing season available to grow the cover crop. If you are trying to control weeds you need to get the cover crop planted before a flush of weeds emerge.
- Be prepared to spray the cover crop field if weeds become an issue. This is especially important if volunteer wheat becomes an issue since it provides a “green bridge” for the wheat streak mosaic virus. The last thing you want is this virus to spread to your or a neighbor’s newly planted wheat.
For more information about this or other soil health practices you can contact me at [email protected] or contact any local NRCS office.
Dale Younker is the Soil Health Specialist with the USDA Natural Resources Conservation Service in Jetmore.