By: Woody Woodruff
After listening to the twelve different experienced cover crop farmers sharing their knowledge at the Conservation Partner’s Tent during the Farm Progress Show this past month, I’m prompted to reflect on my experiences with cover crops on my own farm. My knowledge and ability in implementing cover crops into my corn, soy bean, and wheat rotation continues to grow through trial, error, and success.
The first thing that I learned is that the cash-crop being established after the cover crop makes a big difference in your cover crop species choice. Corn and soybeans are harvested at about the same time for me, which is normally in late September to late October. The wheat in my rotation always follows soybeans, so I use wheat as my cover crop after the soybean harvest. It is after corn that I am always limited in my cover crop choices. The problem is that once the corn is harvested, it is getting late for most things to establish other than cereal rye. Cereal rye is a great weed suppresser but being able to establish more species and having good root growth with lots of residue above ground helps to expand the benefits to growing cover crops. Until this year though, after corn I’ve just been planting cereal rye. I no-till drill my cover crop so it’s planted right after the corn harvest. Cereal rye can be planted the latest of all cover crop species and it winters well. It chokes out weeds in beans as good as chemical herbicides, and even better if the weeds are building up resistance. The cereal rye also releases scavenged nutrients later in the beans’ growing season. This is a yield booster to the soybean grower. This year I had a lot of corn that drowned out so I could plant earlier with more choices and am getting lots of growth on those cover crops. The effect of the early flooding on my corn crop has changed what my goal for next year’s cover crop will be. I can now add more nutrients to the soil, leading to improvements in soil health and the added benefit of a winter habitat.
Wheat might not bring the same economic gains in “yield-verses-price” that corn and soybeans bring, but in the long-term economics I can see greater potential. There are no limits to when and what you plant as a cover crop combination in wheat, being that it is harvested in early July. So there are little limitations to the goals that you can reach: cuting fertilizer costs, reducing the need for herbicides and other pesticides, improving yields by enhancing soil health, preventing soil erosion, conserving soil moisture, and protecting water quality.
I like to diversify different parts of a field with different mixes to see the effect that it has. I inject manure in my wheat stubble so that whatever cover crop is planted can scavenge those nutrients. I have used a mix with some warm season species like millet and sorghum sudangrass. Be prepared to shred the grass in no time at all. Mine has reached 7 feet by the end of August. I have learned that it pays to lower your rate of grasses to help legumes get established. Try different lower rates to see what helps with the legumes being established. This year I am going back to the old standard in wheat of frost seeding red clover and then drilling in a mix after wheat harvest.