Can you build soil health?
Within the realm of soil health, there is the idea presented of "building soil health" in farming systems. But, what does soil health mean? Can you measure whether you've built soil health or not? Does thinking about soil health in this way lead to objectively evaluating a field and coming up with a plan to address issues you see?
Lee Briese, Allie Marks (both well respected consultants with Centrol Ag) and I kicked around ideas about this topic last week as we prepared for our panel discussion at the Corn and Soybean Expo to be held Feb.13. As we provide guidance to farmers, there is a strategic way that we approach the topic of soil health. So, I'll share this approach.
First, we typically don't think about "building soil health." Instead, we objectively look at a field and ask "what are the issues we see?" and how might soil health building practices be incorporated into the system? Issues might be reductions in yield, bare salty areas, weed pressures or soil blowing off the field. The trick is to objectively identify the issue first.
Next, set a goal. Let's use the issue of soil in the ditch as an example. In this case, reducing erosion is the goal. To reduce erosion, the soil needs to be covered with residue (or a living plant like cereal rye). Trapping additional snow in the residue may provide more cover, so that could be used as a tool. With a high-residue crop (corn), figure out how to keep enough residue without causing issues during spring planting. With a low-residue crop (soybean), find a way to build enough residue on the surface to protect the soil.
Next, use goals to develop a systematic plan for action. First, determine which tools can help achieve your goals. For example, if a cover crop could help, what is your current and next crop in rotation? Will you interseed or establish it after harvest and what will you seed to help cover the soil?
Then, consider the residue at harvest. Chopping head or non-chopping head? Straight cut or stripper head? Is the residue evenly spread? Make adjustments to the combine before or at harvest to get residue spread evenly. Tools like vertical tillage can help with uneven residue — don't be afraid to use these tools, but use them on a field-by-field basis.
If there isn't enough residue to reduce erosion, set up this year to address this issue next year. For example, get more residue on the surface by having a fall-seeded or interseeded cereal rye cover crop established the year prior to planting a low-residue crop like soybeans. Cereal rye (living and residue) will help control erosion while providing residue cover that may persist until after soybean harvest. If you still need more residue, then fly on an oat cover crop into standing soybeans. Oats are a great option, because they are flexible for the next crop in rotation and winter kill.
Lastly, learn. Get out in the field to see how the system responds. Determine what worked and didn't work then tweak the system. Each year will be different, so keep that in mind. Success lies in being able to identify the issue, determine a goal, establish and carry out a plan and evaluate the response — not necessarily in the generalization of "building soil health."