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Yield potential of blueberries
For most crops, genetics are not the limiting factor to achieve high yields. It is very seldom, almost never, that a crop is given the needed environment to deliver full genetic potential. For agricultural crops, environment is climate mediated by nutrition, biology, and soil physics.
When nutrition, biology, and soil physics are managed for optimal performance, they mitigate climactic extremes and variability to an exceptional degree, and allow plants to express themselves to deliver more of their genetic yield potential.
If you want to significantly increase yields, don’t just try to improve incrementally by purchasing better genetics. Improved genetics can often deliver 5% -10% yield bumps. Mediating climate by managing nutrition, biology, and soil physics can often increase yields by 20%-50% or more. Which is worth figuring out the most?
We can produce enough food to feed 15 billion people with 30% less land with 1960’s tech, if we want to.
This quote from the podcast interview with Don Huber is powerful and important.
We were shooting for 400 bushels in 1979 and 1980, and now we’re struggling with 250 bushels.
John: Don, in 1979 you were producing 350-plus bushels of corn per acre in a biological soil ecosystem. Today, growers are struggling to produced 250 bushels of corn. We don’t even have a conversation about growing 350 bushels of corn on a commercial field scale. There are a few notable exceptions, but not on a large-scale production system. What happened with that knowledge? Where did it go? Why was it not adopted on a much broader scale?
Don: We started saying we had too much production. We needed to focus on different things. At our land grant universities, a lot of that research and the long-term commitments that breeding programs require for the expression of that genetic potential was closed out. Materials were just given to the private companies to develop their experiment stations.
The universities were happy to not have that long-term commitment. They could then respond to the political pressures, and their programs started being limited to three to five years—for the competitive grant programs on a federal scale. And most of our breeding programs were funded through the Hatch Program and the Smith-Lever Program, which would give the states a constant amount of money on a formula basis for those long-term agricultural developments, which are the reason why we have success in our agricultural programs. They were built on those long-term, continuous programs that were pretty much abandoned as we started looking at the bells and whistles in science rather than at the end product.
Again, we were producing more than we knew what to do with. I don’t know what we’d do with all the corn that we currently produce if we weren’t producing so much ethanol. I mean, that’s the way to use your crop: find a new market for it. Certainly, population growth is a long way from requiring our current production. We could produce enough food for about fifteen billion people with about 30 percent less land—if we wanted to really do that, if we really needed to do that—with the technology that we had in 1964.
We were shooting for 400 bushels in 1979 and 1980, and now we’re struggling with 250 bushels. But sometimes you have to reinvent the wheel. That part of the system was not considered important, and the resources were fractured. In a breeding program, you don’t just turn it on and off with each little whim or political idea that comes along. It’s a long-term program. When we turned all of that material over to the private companies, their interest was the bottom line. There’s a tremendous amount of material that could be manipulated. But as far as that long-term commitment, there hasn’t been any of that.
Genetic engineering certainly has not improved the long-term effects; you get the idea that we can do it all in a laboratory just by switching this system on or inhibiting this particular system. We forget that it’s still a system—an ecology that has to be managed—if any of it’s going to be of value to us. It’s a thought process that’s involved, as well as the necessity. But also, the desire—the innovation—drops out when you forget that you’re a part of a very dynamic, beautiful system that was all put together—when you start focusing on only one thing. Silver bullets may take care of a varmint, but they don’t provide stability in the system.
Insects consume unhealthy ‘weeds’ growing in healthy soil
Not all plants grow equally well in the same soil. Each plant has a preferred microbial, physical, and nutritional environment it thrives in.
When soil balance is optimized for our domesticated plants, the crop plants are healthier than the weeds. Now, the weeds have lower brix readings, and are more susceptible to disease and insects than the surrounding crop.
These lambsquarter plants were growing at the intersection of three fields, growing tomatoes, mixed salad greens, and peas. The last two crops can be very susceptible to aphids. There were no aphids to be found anywhere on the crops, while the lambsquarter was being consumed, as you can see.
The degree of protein synthesis determines insect susceptibility
Plant absorption of ammonium instead of nitrate influences the degree of insect susceptibility. Excessive nitrogen in any form results in excessive soluble amino acids within the plant that enhances insect development and population growth.
From the podcast interview with Larry Phelan.
John: I’d also like to understand the insect attraction piece a bit better. You mentioned that when you have this surge of nitrogen supply on the non-organic farms from the nutrient application period, you have an increased attraction because you have a nutrient-rich food source. Why can insects not utilize plants that don’t contain high levels of amino acids as a food source? They would also contain some level of amino acids, wouldn’t they?
Larry: Yes, all plants are going to have some levels of free amino acids, and they can also digest protein—let’s keep that in mind too. But it’s going to take energy for that insect to digest that protein.
Furthermore, a lot of plants have defenses that involve the inhibition of enzymes that break down protein in the insect. These are called proteinase inhibitors. And in terms of what we call inducible defenses, this is one of the responses of many plants to insect attack. They start the production of these proteinase inhibitors in order to reduce the insect’s ability to digest that protein. It basically knocks out those proteinases in the insect. The insect doesn’t necessarily starve, but it slows its development way down.
Well, in that situation, if you’ve also given that plant these high levels of nitrogen and it’s accumulating these free amino acids, that now short-circuits that plant defense system. So, in other words, the insect doesn’t need those proteinases as much because it’s getting these free amino acids that it doesn’t have to break down.
John: Got it. That was a piece that I had always not fully understood. I’ve heard it described that insects don’t have the capacity to digest complete proteins and that they’re dependent on soluble amino acids as a food source. And that never quite made sense to me. It made sense from a theoretical perspective, but it didn’t make sense to me that plants might have no amino acids versus one plant having very high levels of amino acids.
Larry: Yeah, it’s a matter of degree. And even proteins vary in terms of their digestibility for insects too. And, of course, insects evolve enzymes that are going to be most effective in digesting the proteins they’re likely to encounter, depending on what host plant they feed on.
Livestock profitability exceeds commodity crops
John: Many people are beginning to recognize the value and the importance of cover crops, but there’s still a lot of hesitation around incorporating livestock into agricultural ecosystems. In your estimation, how important do you believe it is to incorporate livestock to the overall ecosystem?
Gabe: Let’s step back and take a look at how our soils were formed. They were formed over long periods of time by large herds of elk and bison being moved across the landscape by predators—trampling, grazing, and then defecating and urinating. A natural nutrient cycling occurred. The animals moved on, so there were long periods of rest and recovery, which allowed for a maximum amount of carbon to be pumped into the soil. Soil health revolves around a carbon cycle.
That’s how our prairie soils were formed, but look what we’ve done with our modern monoculture-type mindset. We’ve removed the diversity, and we’ve removed the animals from the landscape, and now we’re simply not pumping as much carbon into the soil. Now, can we advance soil health without livestock? Absolutely. I have several quarters of land that we’re just not able to graze livestock on because they’re surrounded by housing developments and there’s no water; it’s just not worth the hassle to incorporate livestock onto those acres. We’ve still significantly advanced the soil health on those acres, but those soils will never reach the health of the soils where we are are able to graze livestock.
There are many benefits of having livestock on cropland. The one thing I think producers are really missing out on is the profitability of doing so. I ran some numbers after 2016 and we added $220 net return per acre on the cropland acres where we were able to graze livestock. With margins where they in commodity agriculture today, that’s significant. What producer doesn’t want $220 more per acre? I’m not saying all producers will want to do the things we’re doing with livestock; I’m just saying that they’re missing a major opportunity there.
Cover crops are an absolute no-brainer from a soil health standpoint. If you can integrate livestock, that’s a way to convert those cover crops into dollars. I tell producers that even if they don’t want to do it, there are many people in their communities around the country who would love the opportunity to run some livestock—to enter agriculture that way. Why not benefit your land, help a young person, and integrate some livestock under your cropland?
John: That’s a great idea for including the next generation. When you talk about the economics and the profitability, an additional $220 net per acre—isn’t that a larger net than most growers are getting producing corn?
Gabe: It is. On our operation, we sell very few commodities. We’re doing value-added, direct-to-consumer products—simply because of the dollar return we can generate by doing so. I just shake my head at commodity agriculture today. I have no desire to produce commodities, and I really don’t understand why people do it. There’s just no money in it, unless there’s a major drought somewhere or some external force. We tie our hands, so to speak, when we produce commodities.
I’m not a proponent of the current production model. I think it leaves too many decisions in hands other than our own. Our farm is profitable every year because we set our own prices. We take that out of somebody else’s hands and put it in our own. When you’re able to do that, that really adds to your bottom line and increases profitability significantly.
Farmers need constant learning
Experience, knowledge equity is the most valuable equity young people can have. From Sarah Singla:
if you want to be a farmer, you will have to go to school. In the past we used to say that you should go to school—otherwise you will have to stay on the farm. But today, if you want to be farmer, you must go to school
John: Sarah, you have developed a very interesting perspective in a farming operation. What are some of the memorable moments and the highlights that have led you to make different decisions?
Sarah: I travel a lot. I’ve visited the US, New Zealand, Australia, and some of the parts of Europe, Brazil, Argentina, etc., and I have met very insightful people.
And what I’ve seen is that some farmers are very efficient. They don’t have any tractors or big machinery. First of all, they think. They understand how nature works; they often want to mimic nature. So what I would say to people is to go and learn, learn, learn. In Brazil, they say that efficiency is directly linked to the knowledge you have. The more knowledge you have, the more efficient you will be, and the more profitable you will be. And I truly believe that.
The more knowledge you have, the more profitable you will be on your farm, because the agriculture of tomorrow will be directly linked to knowledge. Farming is the most difficult job in the world, because being a farmer is walking with nature. We have to produce food, we have to respect the environment; we have to have knowledge in agronomy, in husbandry, in mechanics, in accounting.
This means that in the future, if you want to be a farmer, you will have to go to school. In the past we used to say that you should go to school—otherwise you will have to stay on the farm. But today, if you want to be farmer, you must go to school—you must go study. I see that all around the world.
What healthy radishes actually look like
We don’t even know what healthy plants actually look like anymore. Wait, I just said that recently. Oh well, it is worth repeating.
These were radishes from our product test plots at AEA in 2011. Six weeks after planting the radishes without the tops weighed an average of 9 ounces each. They were sweet, crisp, and clear all the way through. No bitterness, no woodiness, and no splitting.
This is what healthy radishes are supposed to look like.
How the form of nitrogen influences insect feeding
The form of nitrogen influences not only the pathogenicity of soil borne fungal diseases, but also susceptibility to insects.
From the podcast interview with Larry Phelan.
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John: As you were looking at these plant-insect dynamics in the field and developing your hypothesis of biological buffering, what was something that surprised you?
Larry: The one thing that was particularly exciting to us was when we took the next step and tested this idea of mineral balance resulting from this biological buffering of organic matter. We started growing plants hydroponically so that we could vary the proportions of different nutrients. The hypothesis we were testing was actually that when the plant was in good mineral balance, you would get both good growth and resistance to insect attack. And then as the plant moved out of balance nutritionally, you would see plant growth go down and insect performance actually go up. And then, ultimately, as the plant was way out of balance nutritionally, we expected the plant to not grow very well and the insects not to do very well either because of the poor host plant.
We tested this with a number of different combinations of nutrients, and the one that was most dramatic—that actually supported this prediction—was looking at soybeans in which we varied the ratios of ammonia to nitrate in the plant. We provided it all the nutrients that it needed in constant levels for all the plants. What we were testing was different ratios between these two different forms of nitrogen. And what we found was that as we increased the amount of ammonia up to about 30 percent, we saw the best plant growth. That ratio of 30 percent ammonia and 70 percent nitrate is where we got the best plant growth.
And then, when we looked at insects, we plucked the leaves off of these plants and then fed them to insects to see how the insects grew. The particular insect we were working with was the Mexican bean beetle. When we fed these leaves to the Mexican bean beetle, we saw just the opposite response. In other words, where the plant was out of bounds nutritionally and not growing very well, that’s where the insects grew the largest and that’s where we saw the best survivorship. But as we moved towards that 30 percent ammonia level, where the plants were growing their biggest, insect survivorship dropped from about 90 percent down to about 30 or 40 percent.
It was a very dramatic effect—even more dramatic than what we were expecting. When we followed up on this and measured the levels of free amino acids in these plants, it was consistent with the prediction. In other words, those plants that were not growing as well, that were out of balance in terms of this ratio, had much higher levels of free amino acids relative to that 30 percent ammonia plant.
Visual indicators of calcium and boron deficiency in corn
When the soil biology does not provide enough calcium during rapid vegetative growth stages, cell division continues imperfectly, resulting in the common leaf ‘zippers’ on corn and other grass crops.
The location of the zipper can also indicate whether boron is inadequate. Adequate levels of boron produces the effect of moving nutrients and water through the plant and leaf quickly to the outer edges. When the zippering effect occurs at the edge of the leaf, it may indicate there is not enough boron present to move calcium to the leaf edge. When zippering occurs in the middle of the leaf, boron may be adequate, but calcium remains low.
When enough calcium is present to remove the zippering effect, plants get significant growth energy from the abundant calcium, and nitrogen requirements drop. This is one reason some farms grow high yielding, high test weight corn with only .35 – .5 lb of N per bushel measured in the system.
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