Introduction
Brad Forkner owns Nutrient Management Specialists and has helped growers all over the country discover the effect that nutrition and biology has on their crops. He states “I'm an energy driven company that utilizes biology to get there. Because at the end of the day, we get paid for the amount of energy that plant can produce”. He has a plethora of knowledge regarding each nutrient and the ways it can effect soil and plants.
Jason and Jaren Schley are part of Agronomy 365 and Baseline Rx. Their knowledge is extensive as well, and they are applying it to each field on an individual level by utilizing AI. Their passion is learning from and with all the different growers and farmers they work with. One emphasis of their fertility is balance. Jason states “it's a lot easier to balance carbon when your fertility's lower. Very hard to do if you want to be a chemical farmer”. When working with SDI (subsurface drip irrigation), Jason states “we don't have to over fertilize and we can constantly give that soil exactly what it needs when it needs it, which gives us a distinct advantage because it doesn't work against the carbon… That's the biggest beauty, I think, in the NutraDrip Netafim system”.
The world of nutrition in humans or plants can be very confusing. Each person you talk to has the “magic bullet” that will give you more energy, raise your yield, fix your problem, etc. However, if no consideration is given to interactions between nutrients, biologies, and food sources, it will create a “cacophony” effect. The goal is to create a “symphony” between all the different components in a soil and what is applied that ultimately increases the amount of energy a plant can produce. We will review a few key nutrients and some of the ways they can affect soil and plant health. If you would like to hear more in-depth information and examples about interactions between nutrients, elements and more, please watch the YouTube video featuring Brad Forkner. Unless otherwise referenced, the information contained here is from Brad Forkner’s presentation.
Silicon
Silicon (Si) is one of the most abundant elements in the Earth’s crust, approximately 28% of the mineral component of soil by weight. Even though it generally is abundant in the soil, it is only utilized by plants in small amounts; however, it is important to plant health, as it turns the plant stress off. Plants absorb Si in the form of orthosilicic acid from soil or a nutrient solution. Soil microbiome increases silicon uptake rate by plants. Copper and silicate (any combination of silicon and oxygen) are needed to hold plants together.
Silicon also reacts with other minerals and nutrients in positive ways, including reduction of phosphorus leaching and improvement of phosphorus availability to plants. It also affects the binding of other nutrients to soil particles including copper, manganese, zinc, and boron) which improves their availability. Silicon also reduces the uptake of toxic elements of aluminum or excessive amounts of sodium. You may be wondering why aluminum would be toxic. There are areas in the Midwest where aluminum levels in the soil are 32,000 pounds. Some of those areas are also high in iron and magnesium. On a very basic level, this will decrease the ability of water and air to move into the soil.
When applying silicon as a foliar spray, it has the potential to increase plant height, stem diameter, root length, and root activity. This increases the mechanical strength of stems. It also improves photosynthetic efficiency, alleviates leaf evaporation and transpiration losses, improves nutrient uptake and metabolism, and enhances resistance to biotic and abiotic stresses.
Silicon is often overlooked in the management of soil and plant health but is worth paying attention to.
Manganese
The second most abundant trace element after iron in the earth’s crust is Manganese (Mn). While it is relatively immobile in the plant, it plays a critical role in regulating redox processes and photosynthesis efficiency. Manganese availability decreases as pH increases, and at a pH of 7.5, manganese availability is not sufficient to meet the plants needs. However, at pH levels below 5.5, Mn becomes very soluble and plants may show signs of toxicity. Manganese imbalances are often causative factors of fungal and bacterial infestations.
Manganese is heavily involved in photosynthesis; it activates enzymes involved in plant metabolism and facilitates plant absorption of potassium. It also regulates homeostasis in a plant. Another nutrient that is worth looking at and learning to regulate in your soil.
Calcium
Calcium (Ca) is an important mineral that can also be harmful in the wrong form or in large quantities. It is responsible for plant cell division, strengthening cell walls, activating a number of plant growth-regulating enzyme systems and contributes to improved disease resistance. Calcium deficiency symptoms include new leaves that are distorted, curled or hook-shaped. Root tips die and root growth is slow. Calcium is immobile within the plant, so symptoms of deficiency appear on younger leaves.
In Kearney, NE, Brad Forkner met with a grower who was struggling to grow anything. He had no-tilled for 15 years and couldn’t get his cover crops to come up. After research, they found this was caused by high iron, and compaction from rains. Due to the soil composition and nutrients, anytime the field got soaked, the Fe+2 iron turned into glue on a paperback, turns loose, and goes down the stream. that didn’t reform, which allowed all the clay particles to go back and lay flat like sheets of paper. This created a plow pan on a no-till field. He has put all his calcium and dry fertilizer on this field for the last 15 years. Calcium plus chloride equals concrete. He now has a concrete wax layer on top of a surface plow pan, and is wondering why the water won’t go into the soil.
Another example involving available calcium: in the Rio Grande Valley they grow watermelons and use calcium to keep them from sunburning. The typical calcium load in soil around Minnesota is 5000 pounds. In the watermelon fields, the calcium load is 27,000 pounds. The chance of getting calcium carbonate to solubilize is zero. We need calcium, so we start looking at different forms of calcium: calcium nitrate, calcium acetate, citracal (Paul Harvey)? We need calcium that isn’t tied up. One product we use heavily down there is fish products that have solubilized or fermented bones; we are bringing in calcium that hasn’t had time to grab ahold of the fossil. This is just another example of thinking outside the box and finding products that work for the uses we need.
Potassium
Potassium (K) is known as the “quality” nutrient due to its ability to increase plant vigor and resistance to diseases and low temperatures and promote healthy root systems. Potassium is essential in sugar and starch formation and is also involved in the movement of nutrients through a plant. Symptoms of potassium deficiency include older leaves that look scorched around the edges or are wilted, yellowing between the leaf veins (interveinal chlorosis) and increased susceptibility to drought and pathogens.
Molybdenum
Molybdenum (MO) is another trace element found in the soil that is highly important for plant growth and vitality. While deficiencies are rare in most agricultural areas, it will show up as a general stunting or yellowing of the plant. A deficiency in this element can also cause nitrogen deficiency symptoms, especially in soybeans, alfalfa and other legume crops. The reason for this is that soil bacteria growing in legume nodules must have molybdenum to pull nitrogen from the air. Sandy soil has the highest risk for being deficient; however, Mo becomes more available with a higher pH, so lime usually will correct this problem if the soil contains enough of this nutrient. Other interactions to note: heavy P applications increase Mo uptake, while heavy sulfur interactions will decrease Mo uptake.
Source: Soil Fertility (2006) by the International Plant Nutrition Institute(IPNI) and the Foundation for Agronomic Research (FAR).
Phosphorus
Phosphorus (P) improves flower formation and seed production while promoting uniformity and earlier maturity. The reason for this being its vital capacity in ATP, which is the main energy source of plants. It is also essential for DNA, cell division and photosynthesis. A deficiency in this nutrient causes small leaves to have a reddish- purple tint, while older leaves become almost black. It also causes stunted growth and poor rooting.
According to Brad Forkner, the inherent problem with soluble phosphate fertilizers is that they don’t always deliver as promised. Phosphate is a triple negatively charged anion which causes it to be strongly attracted to positively charged cations like calcium, iron and aluminum. When phosphorus forms a bond with these other minerals, it is no longer available to the plant. This can happen within hours of an application but can take up to six weeks.
A story about phosphorus from Jason Schley:
“I call him an old fashioned farmer. He still farms, he's 82 today or so. But then I had a young grower that I worked for his dad, he came back from college, and he took over the farm, and he said, I want you to stay on the farm, but I want you to build our phosphorous levels higher.
What he learned from college is, we weren't high enough on the phosphorous. He wanted a bare minimum of 25 parts per million. So when you spread that number, we had some in the 60s, 80s, 90s, and some at 25, but as low as 25. The old fashioned grower, he never applied phosphorous. He had between a 3 and a 7 all his entire, every year we soil sample for him. Between 3 and a 7. First of all, my question always was, we've worked for him since 2001. So 2001, we were at 2016 or 17, and why hasn't those 3's and 7's turned into 0? I've always asked that. Why didn't the 3's and 7's ever go to 0? If what we've been taught is right, that we're going to mine our soil, why aren't we at zero? Why we weren't at 0 is because we continue to precipitate out of this or enzymes, create availability out of this, and drop it back into this pool at all times. It refills itself. What the young guy farmed he was a market farmer. If he could make money planting beans ten years in a row, he'd plant beans ten years in a row. The other grower, again, he was an old fashioned grower. What I mean by that is he had everything in his rotation. He had peas, wheat, sprig wheat alfalfa, oats, corn, sunflowers. He put everything in his rotation on the system, okay? That guy, through our four years of studies, which, again, this four year study, we weren't even looking at comparing farmers. All we were just trying to do was compare soils to learn. But at the end of the four years, the guy that had three and seven part million ended up in number two. Four years for a total uptake of phosphorus. The guy that had the highest phosphorus in our test ended up being waxed. He was chemically farmed. A chemically farmed guy typically can't get enough into the plant. You can build a soil test, but you can't get it into the plant. The reason why is because the higher you push fertility, the more you have to push carbon. They have to balance each other. If you're gonna bring fertility up like this, you better bring your carbon up with it.”
Nitrogen
Nitrogen (N) is probably the most well known and discussed nutrient, especially in corn and bean crops. There is more nitrogen in plants than any other element, except for carbon, hydrogen and oxygen. Nitrogen is also a component of ATP, or the energy source of the plant, along with DNA. This means a deficiency in nitrogen is manifested by stunted growth and yellowing of older leaves and light green younger leaves. It is important to have adequate cobalt, molybdenum, sulfur and nickel if we want to form nitrogen and have it available for the plant’s use.
Magnesium
Magnesium (Mg) is a central compound in chlorophyll, which is essential for photosynthesis and energy for the plant. It also is a phosphorus carrier and is necessary for cell division and protein formation. A lack of Magnesium will cause slow growth and pale yellow leaves. New growth may be yellow with dark spots.
Boron
Boron is a transporter. One customer took his boron reading one week, and it was 100. The next week it was 11. If he didn’t introduce more, it didn’t come back up. It is similar to Vitamin C in our bodies, it goes away. Each time I (Brad) apply something, I like to add a little boron. This doesn’t blow the budget but allows us to keep that available for the plant.
Copper and Nickel
Both copper and nickel are micronutrients that play vital roles in plant processes and energy production. Neither of them are needed in large amounts, but both are good to be aware of and monitor.