We’ve had a couple weeks of Cafe Talks and there are more topics that really stand out that I want to bring to the larger group of Agweek readers. I think these ideas will help you prepare for this spring.
First, managing spring harvest of the 2019 corn that is still standing.
This first idea was brought up by an agronomist from Arthur, N.D., and we’ve been talking about it since because it’s a good idea. If you have a lot of standing corn to harvest this spring, you may get to the point where you need to stop harvesting and start planting your 2020 crop before swinging back to harvest the 2019 corn crop again. If this is the case, consider flying on a cover crop into the standing corn fields so that you can transpire moisture with that cover crop until you can get back to harvest those fields.
This may help with trafficability when you get back to them. We haven’t totally ironed out the approach, but we think using rapid-growing, cool-season crops like oats and radish could work. It was also brought up by another consultant that if you can’t get your hands on oats, then use wheat that you may have on hand. If it’s low quality, maybe double up on the rate. One thought, be sure to check the corn residue on the ground and see if the seed you fly on will even reach the soil to germinate. If not, then this may not be the plan for you.
Second, some of you may have cereal rye growing this spring that you broadcast into corn in 2019. That’s awesome, because it will use moisture early and hopefully give you some trafficability if you turn around and plant something like soybeans in that field.
If the rate was high enough (let’s say over 70 pounds), you may be thinking about leaving this cereal rye cover crop to harvest in 2020 — a way to check one field off the list that you don’t have to plant this spring when you’re busy.
The discussion on this topic at a Cafe Talk yielded a couple things to keep in mind after a lot of input provided on this one from farmers, crop advisors and Extension. Keep in mind that the seed was broadcasted and the cereal rye crown is above the soil — the root system may not be that great. The stand might be a little patchy, so set your expectations to the fact that it was a broadcasted crop meant to be a cover crop and yields will be low. And depending on the fertility situation, a little nitrogen may need to be added. Keep your eye on these fields and make the call for what you plan to do in May.
Third, if you had a prevented planting field in 2019 that was primarily in radish and turnip, avoid corn on that field in 2020. Radish and turnip are non-mycorrhizal and corn is mycorrhizal. If mycorrhizal fungi are missing from the soil for a growing season under a non-mycorrhizal crop, the soil isn’t “primed” for them to be there in 2020 when the field is corn. Corn in 2020 will then be deficient in phosphorus and you may want to pick a different crop.
Plan ahead — if you have another prevented planting field in 2020 and you are doing a radish and turnip mix, add a grass (oats, barley, wheat) that does form that mycorrhizal association, especially if you want to go to corn on that field in 2021.
The overall conversations the past two weeks have been about planning ahead. It seems difficult to plan when there is so much uncertainty, but as you use cover crops this year, be sure to think about what you intend to plant in 2021.
Join us at any of the upcoming Cafe Talks to share more ideas.