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How To Make Cover Crops Fail!

By August 12, 2019December 10th, 2019No Comments

by Green Cover Seed  Sales Agronomist, Dale Strickler 

Everywhere I go to speak, I am told “that wont work around here” whenever I propose a new practice. It doesn’t matter what idea is presented. It just wont work “around here.”  It can work “somewhere else” because “somewhere else” always has some sort of completely unfair advantage in climate or soils or plain luck that poor old “around here” does not possess. One time, I was told by someone that a practice just doesn’t work “around here” and I pointed out a very nearby neighbor who was making that same practice work. “Yeah”, he said, “but everything that guy does just turns out well. He is just lucky.” The irony that maybe that guy is lucky because he is doing the things that “don’t work around here” escaped him. This guy also pointed out that the other guy had “much better soil” than him, even right across the fence. The irony that doing things that “don’t work around here” might just make for better soil also seemed to escape him.

I was talking to an agronomist a few years ago and I brought up the topic of cover crops. He cut me short and said, “Nope. Save your breath. Been there, done that. They don’t work around here. It is just too dry.” If you know me at all, you know that is a statement that will get me bristled up. Especially since this guy lived in an area with more rain than probably half of GCS customers, who are using cover crops successfully. So I felt compelled to gather more information. I asked him what the farmers did. He said they had heard about these radishes, how they could break up hardpans. So they planted them in their wheat stubble, and the next year those radishes “had used up all the moisture” and their corn the next year (2012) was a failure. I prompted him for more information. “Did they graze them?” Yes, they did, he said, because they were short on pasture and needed something for their cattle to eat. “How much did they leave?” I asked. He said because they spent so much money on those cover crops, they ate it all to the ground, because they wanted to get all their moneys worth out of them.  How much residue was left the next spring? He said, the ground was bare, like it had been tilled.  In his mind, cover crops would never work in his area because it was too dry, and the poor results of his customers with them in 2012 solidified that idea.

WHY do cover crops sometimes increase yields of future crops? WHY do cover crops sometimes decrease the yields of the next crop? In previous editions of our Green Cover Seed Soil Health Resource Guide, we have focused on the Five Principles of Soil Health, as developed and promoted by the USDA-NRCS.  These principles are:

  1. Minimize soil disturbance
  1. Keep the soil covered
  2. Keep a living root in the soil as much as possible
  3. Provide diversity
  4. Integrate livestock

You do not see “plant cover crops and you will see yield increases in your next crop” on this list.  What you see instead is a list of principles, that if followed, will improve your soil and dramatically improve your odds of successful crops in the future. If you look at this list, can you see which principles were violated by the customers of this consultant?  They were no-till, so they had #1 covered, and they integrated livestock, so #5 was covered. But from the story, we also know that #2 and #4 were violated.  Principle #2 is keep the ground covered. The livestock were allowed to graze ALL the cover, which tends to increase run-off of rainfall and leave the soil exposed to evaporation. Principle #4 was also violated. The cover crop was a monoculture. Why is that bad?

In this case, the species was one that has no persistent residue, and a very narrow carbon to nitrogen ratio that encouraged decay of the straw it came in contact with. What residue was left over after the grazing rotted away too quickly. If these farmers had understood the principles of soil health and made just two simple changes, with the first to plant a diverse mixture with some species that leave persistent residue, and the second remove the livestock with cover still remaining on the soil, their results may have been much, much more positive.

Soil Health Principle #2 is important. The photo below shows the mistake made by removing too much soil cover. This photo was taken just after wheat harvest, TWO years after a cover crop was grazed on this field. The green strip to the left in this photo is a thick stand of foxtail that came up because the wheat crop was so poor. Why was it so poor? The farmer here knew exactly why. Both sides of the line in this field were planted to cover crop two years previous. To the left of this area, outside the view of this photo, there was a grain sorghum field, while the area in the photo was all wheat stubble planted to a cover crop mix (oats, radishes, turnips, and other cool-season crops that would be lush and green in the fall) for grazing.  It was convenient in this case to run the electric fence down the line you see now separating the green strip from the clean stubble. The cattle were kept on the sorghum stubble and were allowed to strip graze the high protein cover crops to supplement their diet, but were only allowed to remove half the cover cropbiomass on each strip at a time. But due to where the fence was placed, a small part of the cover crop area was included on the side of the fence with the sorghum stubble. This area was predictably grubbed to bare soil, removing all soil cover. The next year, the entire field was planted to soybeans, and the beans did poorly in this area without cover; wheat was planted right after soybean harvest, and as the photo clearly illustrates, the wheat crop was so thin that foxtails were able to receive enough sunlight to grow quite well. The farmer in this case did everything right on all the field EXCEPT for this one little area; violation of just one of the principles of soil health made a dramatic, visible difference in crop yields long after the cover crop was just a memory.

 

I tell that story to illustrate the idea of principles versus practices. One of the most impactful days of my life was during my first year of teaching at a junior college. I had arranged a field trip to a local farmer and I and my students were all very excited because this farmer was rather famous for having raised wheat crops of over 100 bushel per acre, back in the early 1990’s when such a thing was almost unheard of. I thought for sure we were going to learn all sorts of secrets that would enable all of us to go home and crank out 100 bushels of wheat.

When the farmer began to talk, our hopes were quickly dashed and you could see the disappointment grow in the faces of all the students, and I could feel it in myself as well. He began by saying, “I know you are wanting me to tell you how to raise 100 bushel wheat. I cant do that. No one can tell you how to do that. The only person who can tell you how to do that….is you. There is no magic bullet, no secret recipe. You have to learn for yourself how a wheat plant grows and develops, and when the yield components are determined, and what factors reduce yield and how to prevent and manage them. The first year I raised 100 bushel wheat, I applied a fungicide at flag leaf, because I scouted my wheat and I saw that rust was starting and that conditions were conducive to rust. The next year, all the neighbors found out about my yield and wanted to know what I had done, and I told them. The next year, they were all spraying fungicide at flag leaf. I scouted my wheat and there was no rust and the weather conditions did not favor rust. All my neighbors that sprayed fungicide saw no yield increase at all and had spent a lot of money spraying. They were all mad at me, because they felt I had misled them. I had not misled them at all. They asked what I did, and I told them.  I also told them that they needed to learn how to identify wheat diseases, how to scout for them, how to predict which varieties would be most susceptible to disease and would respond most to spraying, and how to figure an anticipated yield loss to wheat disease and balance that against the cost of a spray trip. They didn’t bother to do that. They thought fungicide was the magic ingredient they were all missing. It was not. The magic ingredient is not magic. It is knowledge of the principles of wheat growth, of wheat diseases, of scouting procedures. They were looking for a list of practices that they could follow every year that would give them 100 bushel wheat. There isn’t one. But if you know all the principles behind soil fertility, behind wheat growth, behind wheat disease development, behind weed biology, behind insect biology, you can develop the practices for yourself. If you don’t know the principles, the list of practices will not help you”

We were all stunned in silence. We thought we had somehow been robbed and left his farm crest fallen. But the more I thought about it, he had given us the best advice we could have ever had, which I have paraphrased into “Learn the principles, of which there are few, and you can develop the practices for yourself, and when conditions change, you know how to change the practices.”

Too many people want the same with cover crops. They want the super plant, or the magic mix that will solve all their problems. While there are often plants or mixtures of plants that may very well be a solution to those problems, a failure to manage those plants appropriately can often lead to less than optimal results. Learning WHY those plants work in that situation will almost always lead to the best possible results under the circumstances. Those who choose to educate themselves will have a huge advantage in the future over those who do not.  Too many people think that the secret to being successful in farming is to just keep farming more and more acres with bigger and bigger equipment; if you are losing money on each acre, farming more acres is not going to help you.

The key is to learn principles of HOW soils function and HOW plants grow.  From that knowledge, you will be able to develop your own practices. You do not need to have a college degree to become educated, nor do you need to go back to college to become educated. We live in a time in which self-education has never been easier, or cheaper, or faster. It is possible to sit in your living room and access knowledge from the best minds from all over the world at your fingertips, through the magic of the internet.

At Green Cover Seed, we take pride in the efforts we take to provide opportunities for our customers (and us!) to learn more about plants and soils. While part of this is altruism, we also feel that having customers that are well-informed will have much more positive experiences with our cover crops than those who are just planting cover crops because all the neighbors are planting them.

This year, we will give away 35,000 copies of our 64 page Soil Health Resource Guide that features education articles from the top minds in the soil health and regenerative ag movement.  As you will see as you read through this guide, it is not a sales catalog. There are no prices listed for products, nor any sales “pitches” for any particular product. Just good agronomic information, from not only the people of Green Cover Seed but also from some of the most innovative agricultural minds around the world.  We hope that this guide will help you to further your education of principles, and that your self education goes well beyond this guide. If you have not seen this publication you can view it on-line here or email carli@greencoverseed.com or call her at 402-469-6784 to request free copies
https://greencoverseed.com/wp-content/uploads/2019/04/Soil-Health-Resource-Guide.pdf

Please also take the opportunity to check out our You Tube channel, which has more than 100 great videos and hundred of thousands of hours of viewing! Videos feature Gabe Brown, Dr. Christine Jones, Allan Williams, Paul Jasa, Richard Teague, Doug Peterson, Dr. Jonathan Lundgren, and dozens of videos from Keith Berns and Dale Strickler.
https://www.youtube.com/channel/UCfrK9tSdYXpHFxbhKxgcMbw

 

 

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