Published Mar 6, 2014

Event recap: Mid-Missouri Soil Health Conference

By Margaret Chamas

I was given the opportunity to attend this excellent conference earlier this week, and got more than my fill of cover crops and soil health.  The entire event featured experts in the subject: Gabe Brown, Dave Brandt, Keith Berns, Mike Plumer, Jason Weirichs, and Doug Peterson.

The focus was on the combination of practices – cover crops, no-till, and planned grazing – to improve soil health and resiliency, while increasing profits.  Folks like Dave and Gabe have brought soils from less than 2% organic matter up to 6 or 7%, able to withstand eight or more inches of rainfall in an hour without becoming waterlogged.  The keys, listed by Gabe but reinforced by all, are to imitate nature: something is always growing and covering the soil and sending roots into the ground.  Diversity reigns!  Water and nutrients are cycled throughout the soil and plant profiles through biology, not synthetic inputs; and animals are present.  You can’t argue with someone who produces corn for less than $1.50/bushel and gets gains of over 3 lb/d on grass-finishing cattle.

Many different cover crops and rotations can achieve these results, and there is no one right answer.  Cover crop mixtures, or “cocktails,” will help achieve results more quickly.  In addition to providing flexibility and stability – if weather or soil conditions don’t favor growth of one species, something else will take its space – the mixtures provide better food for the microbes in the soil.  One concept that came up was the inclusion of species that favor AMF – arbuscular mycorrhizal fungi.  These microbes generate the glomelin that holds soil clods together, providing the aggregation and structure so essential to healthy soils.

Some quick thoughts and takeaways:

  • Be smart.  Do your homework.  Will that crop grow in your climate?  When?  Will the winter kill it like you hope?  Can you roll it to kill it, or will you have to use chemicals?  What crop are you planting next – will the cover harbor any pests or diseases?  Ryegrass was hotly-contested.  With one of the greatest root masses of common cover crops able to get through tough compaction layers, it is also notoriously hard to kill, comes in several herbicide-resistant varieties, and may drop seed that doesn’t sprout for a year or so.
  • Be logical.  Plan for what you’re missing in a healthy system.  Do you lack soil organic matter?  Plant high-biomass crops – grasses and those with high C:N ratios – that will leave a good residue.  Do you need more nutrient cycling?  Go for legumes, which will fix N; brassicas to soak up excess fertilizer N; and broadleaves to bring minerals upwards in the soil profile and make them more available.  Do you need forage?  Go for mixtures of forages that combine quality with quantity.
  • Be reasonable.  There’s no silver bullet.  You may not be able to completely cut out herbicide use with cover crops – the cover itself might get away from you, or it might not provide 100% weed elimination.  Especially when you’re building up soils at first, you may need to use some extra fertilizer to get the cover crop growth you want.  Give it time.
  • Be flexible.  Have a contingency plan.  Diversity within your crop rotations and by having livestock will protect you against weather and other challenges, if you’re willing to see the options available.  Can’t get into the field to terminate cover and plant corn or beans?  Graze it.  Chop it.  Bale it.  Then plant something else – maybe grow the cover crop seed you’ll need in the coming fall.  Livestock are an excellent way to use failed crops or covers.  If you farm to provide your own insurance, you can reduce the need for crop insurance from someone else.
  • Most of all…Be creative!  There are almost too many options!  J  Given 100 acres and the ability to plant and graze cover crops, I have no idea what I’d do first.

After two days of intense learning (seriously…two or three 10-minute breaks and less than an hour for lunch were all we got!), I’m even more curious about what cover crops can do for crop and livestock producers.  Below are some links to those who spoke or represented at the conference – make good use of them!  Feel free to shoot an email with any questions.  I don’t think I’ll be able to type up all ten looseleaf pages of notes that I took, but I’ll try and find something if I’ve got it written down.