Abbey Wick, NDSU Extension Soil Health Specialist
By mid-September, options for seeding cover crops in the Northern Plains become more limited and in some cases seeding rates need to be bumped up to get a decent stand. My typical cut-off date for most mixes that include broadleaf cover crops like radish, turnip or peas is Aug. 15. By September, I take broadleaf plants out of the mix because I can't justify the cost of the seed for the anticipated limited amount of growth.
How should you choose cover crops? First, determine a goal for using the cover crops. What do you want to do? Once the goal is identified, then it's time to think about the current crop and next crop in rotation. This is where it can get tricky, so I'll run though some ideas for different rotations.
Wheat harvest (and harvest for other short season crops) is full speed ahead. With the early harvest, some of you may be thinking about seeding cover crops. Here I will share information on how to get started and how to avoid mistakes, along with seed selection for seeding or flying on cover crops post-harvest.
Earthworms are a great indicator of soil health and are easy to look for in the field. In North Dakota, we have about a dozen species of earthworms with the main genus being Aporrectodea, or grey garden worm. Rod Utter, a research technician who has done decades worth of earthworm research at North Dakota State University tells me, "if you call a worm an Aporrectodea in North Dakota, you'll be right over 90 percent of the time."
This past week, water infiltration and runoff were topics in the Soil Health Minute segment on AgWeekTV. These terms are used often when talking about soil health because managing water (increasing infiltration) and minimizing erosion (reducing runoff) are common goals mentioned when farmers start using soil health building practices. Also, infiltration and runoff are incredibly visual amongst different management practices. I'll explain the terms infiltration and runoff and the role management plays. Infiltration
The Red River Zoo is highlighting modern agriculture with the grand opening of a new exhibit at 10:30 a.m. during Agriculture Adventure Day on July 14. This exhibit, sponsored by the North Dakota Corn Council and North Dakota Soybean Council, in partnership with North Dakota State University Extension Soil Health and the Red River Zoo, is an interactive, educational space highlighting conservation, crop production, precision agriculture, end-use products, fuels, and exports.
This year, we want to double our attendees at field days and workshops. We are calling it "Plus One." For each field day coming up, please consider bringing someone with you who is interested in soil health practices like reducing tillage, incorporating cover crops, managing salinity and whole systems. Maybe it's your neighbor who is asking questions about what you're doing, or your lender or insurance provider. Use this as an opportunity to learn and share information together.
I am often asked this question: "Is using only cereal rye as a cover crop enough or do I need more diversity?" My answer is, "It depends on what you are trying to do with that cover crop." One goal of using cover crops is to build diversity in the cropping system, but there are plenty of other goals associated with using cover crops, such as reducing erosion or managing moisture or weeds to name a few. The most important step in using cover crops successfully is to determine what your goal is. You can then pick cover crops around those goals and also crops in rotation.
Managing salinity in fields is not easy and may require multiple tools or approaches to bring salt-affected areas back into some sort of production. I say "some sort of" because it's important to set reasonable expectations for these salt-affected areas. Some of these areas may have been your best land 20 years ago, but things have changed as the salts have redistributed throughout the profile and across the landscape with changes in water amount and movement. Expectations for these areas need to change too.
Linking research to on-farm application is really important, especially in the world of soil health. To do this effectively, farmers should be an integral part of the conversation.