Get More With Less

Almond trial shows using less fertilizer compared to conventional treatments achieves equal to better results

Understanding Soil Quality

Almond acres have been steadily growing in California since the 1980s, and the crop is now California’s number one exported agricultural commodity. With over 2.4 million acres of trees planted, California grows over 85% of the world’s almonds. Virtually all commercially harvested almonds produced in the U.S. come from California. Most of that is due to the climate: warm, dry summers and cool, rainy winters are key to setting the tree up for success. But we know it takes more than a temperate climate to maximize a crop’s potential. AgroLiquid crop nutrition can be a
valuable tool in producing an abundant and quality almond crop. In an effort to determine the best sources, rates, timings and methods of application for this important crop, for the past two years, AgroLiquid has invested in
and run a full-scale research trial in almonds in California.

AgroLiquid has long believed in proving our technology through rigorous research and field testing. In western soils, we are looking at our technology performance compared to conventional fertilizer sources. Almonds are the perfect crop to test our Flavonol Polymer Technology, given how much potassium is needed to produce a crop. AgroLiquid’s
proprietary technology allows us to chelate/encapsulate nutrients within the sweet spot – not too loose, but not too tight. Our two year almond research trial has been conducted by Barat Basabri of Basabri Ag Research in
Newman, CA.

Trial details:
Each plot consists of five trees and was replicated six times across the orchard. Throughout the growing season, 50 gallons per acre (ga/A) of UAN-32 is applied as a constant in every plot.

Plot 1 (Conventional grower standard):
• 10-34-0 applied at 37.5 ga/A
• KTS applied at 40 ga/A
• EDTA Zinc (Zn) applied four times during the season for a total of 2 ga/A

Plot 2:
• Actagro’s Structure® applied at a rate of 25 ga/A
• KTS applied at 40 ga/A
• EDTA Zinc (Zn) applied four times during the season for a total of 2 ga/A

Plot 3:
• AgroLiquid’s PrG™ applied at 15 ga/A
• KTS applied at 40 ga/A
• EDTA Zinc (Zn) applied four times during the season for a total of 2 ga/A

Plot 4:
• AgroLiquid’s PrG applied at 15 ga/A
• AgroLiquid’s Kalibrate™ at a rate of 13.2 ga/A
• EDTA Zinc (Zn) applied four times during the season for a total of 2 ga/A

The results of the two-year averages are as follows. Plot 1: The “Grower Standard” of 10-34-0 + KTS yielded an average of 2,616 lbs. per acre. The second plot where Structure® was used in place of 10-34-0 + KTS, yielded a two-year average of 2,825 lbs./acre. The third plot was AgroLiquid’s PrG + KTS which yielded an average of 2,840 lbs./acre. The final plot was a full AgroLiquid program using both PrG + Kalibrate which yielded a two-year average of 2,829 lbs./acre. Yield results in the last three plots were comparable. For complete details on the almond trial please refer to the AgroLiquid website: research.agroliquid.com where all of our research data can be found dating back to 1983.

Potassium and Forage Quality

Potassium and Forage Quality

Dan Peterson, Field Agronomy Manager

 

The subject of forage quality and its relationship to cow health and milk yield is a fascinating, yet highly complex subject. In the Midwest, Northeast, and West, dairy forages are primarily alfalfa and corn silage; Other crops, such as pea and oat mixtures, also play a role. Grass forages, including the various sorghums, play a larger role in more southern areas where it is difficult to grow alfalfa. What are the factors involved in producing high quality forage? One factor that should not be overlooked is fertilizer and soil fertility.

 

AgroLiquid is actively researching how fertilization practices influence forage digestibility and quality. Why digestibility? Think of a cow as a milk “factory”. The primary factor that limits production is how much “raw material” the factory can process each day. So, for example, if our “milk factory” can consume a maximum of 85 pounds of feed per day, the amount of energy and nutrients contained within that 85 pounds that the cow is able to extract and utilize is what determines how much milk that cow can produce. Differences in the amount of energy extracted (how digestible the feed is) directly correlates to the amount of milk that factory will produce. Why not just feed the very highest energy feeds possible – grain and fats? The answer is that cows are ruminants, having multiple “stomachs”. Their digestive system uses bacteria and enzymes to digest fibrous plant material. For their digestive system to work properly it must have large amounts of digestible and indigestible fiber. Fats (like vegetable oils) largely pass through this system undigested. This system is also limited to how much non-fibrous concentrate (grains) it can handle. Why is alfalfa so important as a dairy cow forage? The reasons include its overall yield, higher digestible energy content compared with grasses, its high levels of usable protein, and its mineral nutrient content including the critically important calcium (why milk is a great source of dietary calcium).

 

Of the three macronutrients, nitrogen (N), phosphorous (P), and potassium (K), potassium may the least understood in how it influences forage digestibility. Potassium plays a large role in the yield and quality of forage crops. Potassium plays a key role in the photosynthesis, respiration, translocation and many enzyme systems in plants, and also increases disease resistance. For alfalfa, potassium is a dichotomy of sorts. It strongly influences yield, but only to a point – I will discuss that in greater length later in this article. Other ways it is important include improving the level of carbohydrates stored in alfalfa roots. Greater stand persistence is a result.

 

Maximum alfalfa yields are usually reached with potassium concentrations in midstem samples of 1.25 to 1.75% and in the top six inches of the plant of 2.0 to 2.5%. Higher concentrations are undesirable in alfalfa because it reduces calcium and other element concentrations, thereby adversely affecting the cow’s utilization of the forage and increasing the occurrence of “milk fever” after calving (an acute deficiency of blood calcium). The way it happens is this: As dairy cows enter the lactation stage “freshening” prior to calving, large amounts of calcium leave the cow’s blood and enters the milk she is now producing faster than it can be replaced. This decreased calcium concentration in the blood lowers the blood pH, causing nerve disorders, muscle weakness, loss of appetite, paralysis, and subsequent death if not treated immediately. The rations for freshening cows should therefore be relatively anionic (lower in potassium) in the month prior to calving to raise blood calcium levels. But, having a steadily available supply of lower potassium alfalfa is difficult because producers often fertilize for high forage yields with potassium chloride fertilizer without regard to actual soil test levels, and in trying to maximize alfalfa yields. Through soil testing, lower potassium concentrations in forages are possible by avoiding building soil potassium to higher levels than necessary and using careful fertilization practices.

 

The most common source of potassium fertilizer is potassium chloride, a pure salt. It’s well known that high rates of potassium chloride often create a chloride toxicity, particularly where significant soil chloride levels are already present, which is often the case where manure is spread. Excess chloride can also reduce plants’ uptake of other vital nutrients like nitrogen, sulfur, phosphorus, boron and others, which often takes a heavy toll on yields and forage quality. The very high salt of potassium chloride can also lead to reduced soil microbiological activity and poor germination of new seeding.

 

According to David Weber writing in the Progressive Dairyman, “Particularly in fresh cows, research shows how alarming forages high in chloride can be for performance and health. In fact increasing levels of chloride in lactating diets has a negative effect on feed intake and milk production. To avoid these pitfalls, diets must be formulated to account for the variability in forage chloride levels to optimize milk production. Chloride is continually recycled on the dairy. Potassium exits the farm in many avenues, including in the milk. Chloride, though, is left behind in manure and applied back onto the fields. The rising chloride levels and the continuous potassium chloride fertilization have resulted in extreme forage variability in macromineral levels”. Weber found that some forages had chloride levels over 1 percent of ration dry matter, which negatively affects lactating cow performance and health. To account for the chloride being regularly applied through potassium chloride fertilizer, routine chlorine testing in all forages is advised. This information will allow ration formulation to meet cows’ needs.

Forages – We Can do Better — a lot better!

Forages:  We can do better – a lot better!

By Dan Peterson, Field Agronomy Manager

 

When the acres of pasture, grass hay, alfalfa, corn and sorgum silages, and grazing wheat in the plains are all added up, forages account for by far the most acreage of any US crop. In fact, land used for grazing is over 780 million acres – equal to 40% of the entire land area of the US and nearly double the land used for other crops of all types. Add to that the 61 million acres of alfalfa, 15 million for corn and sorghum silages, then add in the grass hays and others, and you can see that forages comprise the vast majority of US cropland. And yet, it could be said that forages continue to be neglected when it comes to fertilization. The majority of grazing lands receive no fertilizer of any kind, with the resulting low forage yield/lower daily rate of gain being widely accepted on land with low perceived value. At AgroLiquid, however, we are discovering that even a very modest rate of our products applied at the right time results in a large return on investment.

 

Why?

 

All of the meat and milk animals that consume forages are, in fact, designed to consume forages – not grains. So even though we do supplement ruminant animal diets with grain, these animals must still have forage as a major component of their diets. Normally when a grower or agronomist is asked why we fertilize forages, the answer will be to obtain higher yields. While that is important, what if we could actually increase the quality and digestibility while at the same time increasing yield?

 

Our answer is yes – yes we can

 

We can, in fact, increase yields and at the same time increase the digestibility and energy content of forage crops. In our trials, here is what we are discovering:

  1. We increase the sugars, protein, and palatibility in grass hays, and the actual Neutral Detergent Fiber (NDFD) digestibility also improves substantially.
  2. On alfalfa we routinely achieve an increase in protein, lower lignin, higher water soluable carbohydrates (sugars), significantly higher Relative Feed Value (RFV) and Relative Forage Quality (RFQ) numbers, higher NDFD tests, and more extractable net energy.
  3. On permanent grass pastures we see strong yield and quality responses to low and economical rates of High NRG-N, Pro-Germinator, Sure-K, and fertiRain.
  4. We do not yet have enough data to determine if AgroLiquid nutrients have similar effects on corn and sorghum silages. More silage trials are planned in 2018.

 

What is the value to the beef cow/calf, feedlot manager, or dairyman for quality and digestibility improvement in their forages – even their low value forages such as “grinder hay”? Here are some interesting numbers as an example:  Every one whole number increase in the alfalfa NDFD test increases milk production by a half pound more milk per day. We often see an eight point increase in the NDFD score in alfalfa treated with a foliar AgroLiquid program. So if we were feeding a ration with 100% of that alfalfa, the cows would produce four pounds more milk per cow per day. But in real life alfalfa is fed at an average of closer to 25% of the total mixed ration on large dairies. If a dairy operation with 2,000 cows in lactation is feeding alfalfa at 25% of their total mixed ration here is how the math works:  4 pounds times 25% = 1 more pound of milk per cow per day.  On this dairy that’s 2,000 more pounds per day. Milk is priced  per hundred weight, so that’s 20 more pricing units per day times current “mailbox” price of $18 (varies by state) = $360 more per day = $131,400 more per year. In this example, based on a real operation, their extra cost was $15,000 per year (replacing a portion of their standard dry program) which netted them $116,400.

 

One significant factor we are learning in our many trials is that when individual AgroLiquid products replace the comparable commodity fertilizer product, it will, in most situations, improve the forage quality. For example, if Pro-Germinator replaces 11-52-0 on a grass pasture, the quality of the grass will be better. Likewise if Sure-K replaces or reduces dry potash, the forage treated with Sure-K will have better quality.  Where High NRG-N has replaced urea or UAN, the resulting grass pasture or hay will have higher quality, a larger root mass, and more consistent growth. Can an AgroLiquid program entirely replace a commodity dry program? Yes it can – but you may not always want to. For example, when we have tested yield and quality results where Sure-K is used as a supplemental foliar treatment following a top-dress application of dry potash, we usually see a significant increase in yield and quality versus the dry potash alone. So where soil test K is low, we can use dry potash and Sure-K to the grower’s advantage. On the high pH soils of the Central Plains, however, Pro-Germinator clearly performs better than 11-52-0, achieving both higher yields and improved forage quality, and should be recommended as full replacement for the dry.

The Importance of Micronutrients

By Marcus McClure, AgroLiquid Regional Agronomy Manager

We know plants use micronutrients in very small amounts, but they are just as essential for plant growth as primary (N, P, and K) and secondary (S, Ca, and Mg) nutrients. Any one of them can limit growth and yield potential – and even cause plant death when deficient.

Why are micronutrient deficiencies increasingly being seen in the soil? There are several possible causes:

  • Increased yields due to various technology improvements have led to increased yields, meaning higher demand by the crop and more removal of micronutrients from the soil
  • Any type of land preparation which results in the removal of several inches of topsoil results in a deficiency of certain micronutrients on the cut areas
  • High phosphorus levels can cause micronutrient tie-up, leading to deficiencies

Let’s take a look at some of the micronutrients, and why they are important to the plant:

BORON (B)

Boron is necessary for cell division and differentiation. It helps maintain a balance between sugar and starch and aids in the movement of calcium. Boron is also essential for the germination of the pollen grains and pollen tubes in plants and has a direct effect on yield. No pollination, no crop.

COBALT (Co)

Cobalt plays a critical role in the overall growth of plants. Cobalt is necessary for the processes of stem growth, elongating the coleoptiles, and expanding leaf discs. A cobalt deficiency will reduce or stunt plant growth and reduce seed germination.

COPPER (Cu)

Copper aids in root metabolism and the utilization of proteins. Copper is essential for better stalks or stems and standability. It is also key to seed coat resiliency, disease control, test weight, and seed size.

IRON (Fe)

Iron is required for the formation of chlorophyll in plant cells. It activates respiration, photosynthesis, and symbiotic nitrogen fixation. Low iron levels in the plant result in poor energy transfer from leaves to growing points or fruiting structures thus slowing growth and lowering yields.

MANGANESE (Mn)

Manganese plays a major role in the production of chlorophyll. It directly affects the health of the crop and whether a plant reaches maturity or not. Manganese deficiency is a widespread problem, but is most often found in sandy soils or in soils with a pH above 6.0.

MOLYBDENUM (Mo)

Molybdenum acts as a catalyst in nitrate reduction, and in nitrogen transport and utilization within the plant. Molybdenum is also associated with disease resistance in plants.

NICKEL (Ni)

Nickel is important in nitrogen metabolism because it is a component of the urease enzyme. Without the presence of nickel, urea conversion is impossible. It is required in very small amounts, with the critical level appearing to be about 0.1 ppm.

ZINC (Zn)

Zinc is necessary for chlorophyll and carbohydrate production. High yields are impossible without zinc due to its importance in growth, metabolism, and photosynthesis. High soil phosphorus, soil organic matter, biological activity, and irrigation play a role in zinc availability.

Most growers and agronomists focus on macronutrients to improve yields and crop quality. However, micronutrients obviously play a pivotal role in crop development. If micronutrient deficiencies persist year after year, they will continue to damage crops regardless of the nitrogen, phosphorus and potassium applied. Before adding micronutrients to the soil, it is important to know what the soil already has available. A soil test analysis that includes micronutrients will give a snapshot of what is available to the plant. The soil test is especially important because many micronutrient deficiencies cause similar symptoms in the plant and can be difficult to identify. Deficiencies can also be caused by many factors, such as soil pH, moisture, temperature, and the presence of other compounds or nutrient tie up. If a crop is not reaching its full potential, or the same problems keep appearing, contact you crop nutrition expert to help investigate potential micronutrient deficiencies.

Take Control of Your Fertility Program

Take Control of Your Fertility Program

Dylan Rogers, Sales Account Manager for AgroLiquid

Almonds in blossom
Almond tree blossom

The 2020 almond crop is upon us. Trees are beginning to break dormancy, soon full bloom will occur, and the honeybees will be busy pollinating what will be our highest yielding crop to date – we hope. There are many factors that will affect the yield potential of this year’s crop; some we can control and others we cannot. Mother Nature and the weather are out of our hands – all we can do is hope that it works in our favor. We can fight disease and insect pressure, but we cannot prevent it completely. One factor we do have complete control over, however, is our fertility program and ensuring we supply the trees with the nutrients they need to produce that high-yielding crop.

Soil Samples

A great starting point for building your seasonal fertility program is by assessing what you have in the soil. Looking at a current soil sample will give you an idea of what needs to be done in season to ensure adequate fertility for maximum yields. There are multiple things to consider when reading a soil test. You may see that most or all of your nutrient levels read adequate or high; However, the ratios of some nutrients are more important than the levels. For instance, iron and manganese are antagonistic to each other. You may have adequate levels of both nutrients in your soil, but if the ratio is off, you may see symptoms of deficiency. You need more iron than manganese in the soil. The ideal ratio is 2:1 iron to manganese. The closer this ratio gets to 1:1, the more likely you will see an iron deficiency in season. The ratio of phosphorus to zinc is also an important factor. A ratio of 10:1 phosphorus to zinc is the ideal balance between these two nutrients. If phosphorus levels get too high, it may induce a zinc deficiency. These are just two examples of many ratios that should be addressed in your soil. A soil sample will ensure you have the information you need to get off on the right foot to maximizing this season’s yield.

Bud Break, Pink Bud, Bloom

During the period in which fruit buds are swelling, the trees are also working below the soil surface. A new flush of feeder roots are pushing out, and having an adequate supply of phosphorus and soil moisture is critical in the development of these new roots. Choosing a phosphorus fertilizer that is protected from tie-up in the soil ensures the most return on this investment. Following bud swell and new root development will be bud break, a period in which flower and pollen development are crucial. These fruiting buds that will become flowers are the fate of this season’s crop, so we do everything possible to protect and ensure their viability. Foliar applications of phosphorus, calcium, zinc, boron, and molybdenum can be beneficial, as they play important roles in all aspects regarding pollen.

Fruit Development

 The tree’s highest demand for nitrogen and potassium is from fruit set to harvest. Supplying these two nutrients in adequate amounts is crucial to achieve a high yielding crop. Nitrogen is a critical component of many plant parts and functions. It is needed to produce chlorophyll, DNA and RNA, and to synthesize amino acids. Studies have shown that for every 1,000 pounds of kernels removed, about 85 pounds of nitrogen are removed after accounting for fertilizer inefficiencies. Choosing a nitrogen fertilizer that is low in salts and less likely to leach or volatilize will ensure optimum uptake by the tree and give you the most return on your fertilizer investment. Potassium is also very important for many plant functions and is required in large amounts. Potassium plays a major role in the opening and closing of stomata, photosynthesis, translocation of sugars, and many other plant processes. Studies show that for every 1,000 pounds of kernels removed, around 90 pounds of K20 are removed. There are some important things to take into consideration when choosing a potassium source. Almonds are very sensitive to salts such as chlorides and hydroxides. Some fertilizers can even be toxic if applied at higher rates. Choose a potassium source that is free of chlorides and hydroxides to ensure maximum uptake and to minimize potential for crop injury.

Taking control of your fertility program this season will help achieve maximum yield potential. Again, there are multiple factors that are out of our control so taking advantage of the factors we can control is important. Choose your fertilizers this season with plant and soil health in mind to maximize your return on investment.

Almond fields

The 12 days of Crop Nutrients

Day 4 

Since I have already lost the theme of this thread (being a tie with the beloved carol, The 12 Days of Christmas), I won’t try to draw a connection between four calling birds and potassium – although I’m sure I could if I tried hard enough.

 

Potassium in one of the primary plant nutrients. It is essential for the transport of sugars and the formation of starches and oils. Potassium helps to regulate the opening and closing of a leaf’s stoma which are important for the efficient use of water by the crop.

Potassium deficiency in almonds
Apple with a potassium deficiency
Potassium deficiency in grapes

 

 

 

 

 

 

Potassium also promotes root growth, increases a plant’s resistance to disease and cold temperatures. It improves the size and quality of fruits, nuts and grains, and is essential in high-quality forage. Crops that produce large amounts of carbohydrates (sugars) require large amounts of potassium – sometimes even more th an nitrogen! Cotton, almonds, alfalfa, grapes, cherries, and peaches are all especially fond of potassium.

 

Common symptoms of potassium deficiency:

  • Slow growth
  • Tip and marginal leaf burning
  • Burning of older leaves
  • Weak stems and stalks causing lodging
  • Low fruit sugar content and shriveled seeds
Corn with a potassium deficiency

The 12 days of Crop Nutrients

Day 3 

On to day three of crop our nutrients post. If you aren’t following along in our 12 Days of Crop Nutrients, be sure to check out day 1 – phosphorus, and day 2 – calcium. For our third day of crop nutrients, we’re going to discuss the micronutrient boron. It’s been said before, but it bears repeating: while crops needs less of a micronutrient, those nutrients are no less important to maximizing crop potential.

Boron deficiency in almonds

Boron (B)

Boron is necessary for cell division and differentiation. It helps maintain a balance between sugar and starch and aids in the movement of calcium. Boron is also essential for the germination of the pollen grains and pollen tubes in plants and has a direct effect on yield. No pollination, no crop. In other words, it may be a micronutrient, but it’s no less important to crop potential than nitrogen, phosphorus or potassium.

Cauliflower with boron deficiency

Boron is a nutrient that becomes immobile once it is utilized within a crop. Therefore, it is essential to have an available boron “pool” within the soil throughout the growing season. Some symptoms of boron deficiency can include:

  • Shortened plant nodes
  • Thickened, brittle and curled leaves
  • Terminal growth dies and / or young growth tissue deteriorates
  • Reduced flowering and fruit set, poor seed set

Malformed or small fruits and physiological disorders associated with root and tuber crops.

The 12 days of Crop Nutrients

Day 2

Welcome to our second day of the crop nutrients post. Hopefully you caught our first day – where we focused on phosphorus. In the traditional Christmas carol, the second day is two turtle doves. Since I don’t have any clever alliteration ideas for this one, I am going to talk about a secondary nutrient: calcium.

 

Calcium (Ca)

Calcium is a secondary plant nutrient that stimulates root and leaf development, activates several plant enzymes, and is required by nitrogen-fixing bacteria. In the soil, calcium indirectly influences yield by reducing soil acidity. It also helps improve root growth conditions, molybdenum availability, and uptake of other nutrients. In the soil, calcium indirectly influences yield by reducing soil acidity, which in turn lowers the solubility and toxicity of manganese, copper, and aluminum.

Alfalfa calcium deficiency comparison. (Left has deficiency, right does not)

Calcium is the third most important element in a plant. And, calcium is the fifth most abundant element on the planet. It makes sense that traditionally, growers don’t apply much calcium, because they assume the plant will get what they need from the soil. But, soil calcium is usually found in a form that is not easily taken up by plants.

 

Calcium deficiency in an apple

As an example, in an apple tree, the leaves, new shoots, and fruit all take calcium. The nutrient will be found in the tissues and the root, but the fruit cannot compete with the other parts of the plant. Hence why the fruit often doesn’t get enough calcium. That is why calcium deficiencies are evidenced on the fruit, rather than the rest of the tree. In apples, a calcium deficiency causes a disorder known as bitter pit. Bitter pit is a physiological breakdown of the cell walls in the fruit that occur below the skin of the fruit. For that reason, when scouting for calcium deficiencies in fruit trees, it is important to test the fruit, rather than relying solely on leaf or soil tests. Signs of calcium deficiency common in all crops include abnormal dark green foliage, premature shedding of blossoms and buds, and weakened stems.

 

Further problems with the calcium levels in the plant, and therefore in the fruit, are often caused by changes in the weather. In high temperature, low humidity conditions, for example, transpiration will increase dramatically, causing the plant to use more water. In irrigated crops, if watering has not been well scheduled, even soils with good levels of calcium can have problems in the fruit caused by calcium deficiency, such as blossom-end rot in tomatoes. This is the time when we need a fast calcium fertilizer that can be applied by foliar.

 

Common symptoms of calcium deficiency:

  • Death of growing points
  • Abnormal dark green foliage
    Example of calcium deficiency in lettuce
  • Premature shedding of blossoms and buds
  • Weakened stems
  • Tip burn of young leaves (primarily in vegetable crops)
    Calcium deficiency in corn
  • Water soaked, discolored areas on fruits
    Canola with a calcium deficiency

The 12 days of Crop Nutrients

Is anyone else missing the Christmas carols? Because we’re in the midst of the 12 Days of Christmas, and because the lack of seasonal music has me feeling a little deflated, I’m going to borrow the theme of the beloved Christmas carol “The 12 Days of Christmas,” and turn it into the 12 days of crop nutrients.

Partridge in a Pear Tree – or Phosphorus (P)

The alliteration here demands that we feature phosphorus first.

Phosphorus is an essential plant nutrient and very important for numerous plant processes and crop production. It is a vital component of DNA and RNA, the building blocks of proteins and protein synthesis. The adenosine triphosphate molecule (ATP) molecule is responsible for storing and transferring all of the energy produced and needed by the plant. At the core of this ATP molecule are phosphates, responsible for all of the activity of ATP. Phosphorus also plays a major role in the stimulation of new root growth.

So, P is Important

Our crops clearly need phosphorus to thrive. So, what do we need to worry about when supplying P? “Tie up” within the soil is the primary concern with phosphorus fertilizers. In acidic soil conditions, P will tend to get tied up by iron, aluminum, and manganese. In basic soil conditions, calcium will be the major component of phosphorus tie up.

Phosphorus deficiency symptoms in corn
Phosphorus deficiency in corn

Phosphorus is most available to the plant in a soil pH range of 6.3-6.8. Common liquid fertilizers, such as ammonium polyphosphate (10-34-0) and orthophosphate (9-18-9), applied in the early spring will also have a likely chance of being tied up if a gypsum application was made in the fall.

Choosing a phosphorus fertilizer that is protected from tie up will ensure that you get the most out of your fertilizer investment and that your crop will receive the required amount of phosphorus needed.

Available P versus Usable P

Not to mention, applying phosphorus as a crop nutrient can be tricky. Just because phosphorus was applied to the soil does not mean that it is doing what you want it to do: feed the plant!  AgroLiquid founder, Douglas Cook, was known to say that all applied fertilizer is available, but not all applied fertilizer is usable. Sounds funny, but it’s true. What’s the difference? All fertilizer is available to plants — it’s right there for the taking. But it may not be usable. In order for a nutrient to be usable, it must be close to the roots and it must be in a form that the plant can absorb.

Nutrients like nitrogen can be lost to leaching or volatility before absorption. Potassium can be strongly held by clay in the soil and not able to be taken up by roots since it is not in the soil solution. Phosphorus can also become unusable. Phosphate is negatively charged and can react with, or be fixed, by positively charged elements in the soil (cations). Plants cannot take up these compounds of calcium phosphate, aluminum phosphate or iron phosphate. Estimates are that the crop will utilize only around 20% of applied phosphate fertilizer during the season after application, and in following years, the amount becomes progressively less as it reverts to mineral forms. Again, the nutrients are there and available, but they are not always usable.

Out of Sight, Out of Mind

You cannot actually see the fate of phosphate molecules in the soil, so it’s not necessarily something growers are thinking about. If only a small percentage of your planted seed came up, you would probably be mad because you can see that loss. Similarly, only a small percentage of the applied phosphate is usable. However, you cannot see this, so it is not a concern.  But it should be.

Placement is Key

Phosphate fertilizer works best if it is placed close to the seed at planting. In the picture at the left, it is apparent that phosphate fertilizer placement is affecting growth. Five rows of the plot had 5 gal/A of Pro-Germinator applied through the planter, and the sixth row had no planter fertilizer.

Phosphorus source comparison in field corn
Fertilizer placement comparison using Pro-Germinator in corn

The rows with the In-furrow placement are tasseling, whereas the 2×2 placement has yet to tassel. Close inspection shows that the corn with the 2×2 placement is taller than the row with no fertilizer, but it is behind the rows with the in-furrow placement. This shows that phosphorus placement for earliest root access affects plant growth and yield. Additional testing at the North Central Research Station has shown that in furrow placement can out-yield 2×2 placement by almost 5 bu/A.

In order for phosphorus fertilizer to be most effective, it needs to be usable. Usability is increased by placement close to the seed row and protection from fixation losses. Pro-Germinator is the only fertilizer that does both.

 

 

 

Common phosphorus deficiency symptoms:

  • Stunted plants
  • Leaves may be darker green or begin purpling
  • Leaves may curl upward
  • Maturity can be delayed
  • Poor seed set
  • Poor fruit quality
Phosphorus deficiency in citrus fruit
Phosphorus deficiency in citrus fruit can result in poor fruit quality.
Purpling leaves, like those in this canola plant, can be a symptom of phosphorus deficiency
Purpling leaves, like those in this canola plant, can be a symptom of phosphorus deficiency

 

 

Building and Managing Soil Phosphorus

By: Dr. Jerry Wilhm, Senior Research Manager

Clearly, phosphorus is important for growing crops. It is involved in many functions within a plant like energy storage and transfer (ATP/ADP), protein synthesis, photosynthesis, nucleic acid (DNA/RNA) synthesis, nutrient movement through cell walls and many more processes. Therefore, it pays to make sure phosphorus does not become deficient in plants.

However, applying phosphorus as a crop nutrient can be tricky. Like all nutrients, phosphorus must be managed. In other words, just because phosphorus was applied to the soil does not mean that it is doing what you want it to do: feed the plant!  AgroLiquid founder, Douglas Cook, was known to say that all applied fertilizer is available, but not all applied fertilizer is usable. Sounds funny, but it’s true. What’s the difference? All fertilizer is available to plants — it’s right there for the taking. But it may not be usable.

In order for a nutrient to be usable, it must be close to the roots and it must be in a form that the plant can absorb. Nutrients like nitrogen can be lost to leaching or volatility before absorption. Potassium can be strongly held by clay in the soil and not able to be taken up by roots since it is not in the soil solution. Phosphorus too can become unusable. Phosphate is negatively charged and can react with, or be fixed, by positively charged elements in the soil (cations). Plants cannot take up these compounds of calcium phosphate, aluminum phosphate or iron phosphate. Estimates are that the crop will utilize only around 20% of applied phosphate fertilizer during the season after application, and in following years, the amount becomes progressively less as it reverts to mineral forms. Again, the nutrients are there and available, but they are not always usable.

This may not be a concern to growers because you cannot actually see the fate of phosphate molecules in the soil. If only a small percentage of your planted seed came up, you would probably be mad because you can see that loss. Similarly, only a small percentage of the applied phosphate is usable. However, you cannot see this, so it is not a concern.  But it should be.

 

 

 

 

Phosphate fertilizer works best if it is placed close to the seed at planting. In the picture at the left, it is apparent that phosphate fertilizer placement is affecting growth. Five rows of the plot had 5 gal/A of Pro-Germinator applied through the planter, and the sixth row had no planter fertilizer. The rows with the In-furrow placement are tasseling, whereas the 2×2 placement has yet to tassel. Close inspection shows that the corn with the 2×2 placement is taller than the row with no fertilizer, but it is behind the rows with the in-furrow placement. This shows that phosphorus placement for earliest root access affects plant growth and yield. Additional testing at the North Central Research Station has shown that in furrow placement can out-yield 2×2 placement by almost 5 bu/A.

Pro-Germinator has carbon encapsulation for protection against fixation losses that affect other forms of phosphate fertilizer. This is the  Flavonol Polymer Technology that AgroLiquid developed to prevent fixation losses and enable extended nutrient release into the growing season. This also increases crop safety and can be effective at lower rates than those of conventional fertilizer like 10-34-0. In this experiment from the North Central Research Station, the lower rate of Pro-Germinator enabled a higher corn yield than that with the higher rate of 10-34-0. Closer inspection shows larger ear size and the darker yellow corn indicates advanced maturity.

In order for phosphorus fertilizer to be most effective, it needs to be usable. Usability is increased by placement close to the seed row and protection from fixation losses. Pro-Germinator is the only fertilizer that does both.