In some fields pollinators will only work blossoms in the morning, until around 9 or 10 AM. In other fields of the same plant species, pollinators are collecting nectar from dawn to dusk.
In some orchards, honeybees prefer the dandelions and healing herbs (weeds) to the fruit tree blossoms. In other orchards, bees ignore the dandelions, and are visiting fruit tree blossoms all day long.
Healthy plants produce larger amounts of nectar that has a higher sugar content, which increases it’s attractiveness to pollinators.
Less healthy plants have less nectar, and the sugar content can be dramatically lower.
As an example, the sugar content of apple nectar can vary from a low of 2% up to 60%.
When apple blossom nectar contains 2% sugar, do you think honeybees will prefer the dandelions over the apples or vice versa? What about when the sugar concentration is 60% in the nectar?
An agronomist with decades of experience has reported that honeybees avoid visiting flowers where the nectar brix is below 7, since they consume more energy than they gain in return.
Before our transition to regenerative agriculture and nutrition management, honeybees would only visit cucurbit crop blossoms until 9 AM. Within two years of changing nutrition management, they were present all day.
You can observe how much time a bee spends on each flower. A flower worth visiting for 80 or 90 seconds will contain much more nectar (and of higher quality) than a flower only worth visiting for 5 seconds.
You can also observe how long during the day pollinators are active in a crop.
Both of these observations will correlate to nectar attractiveness, and to overall plant brix readings and health.
Bruce Tainio pioneered the use of plant sap pH as an indicator for disease and insect susceptibility in 1988. We have used this tool in our consulting work since the beginning, and have found it invaluable. Today, pH is included in lab sap analysis because of Bruce’s work.
More recently, we have learned from Olivier Husson’s work, that measuring pH by itself is incomplete, since the environmental parameters organisms require to become virulent are at least two dimensional, as they are determined by both Eh and pH, not by pH alone.
Bruce wrote this outline we shared in our newsletter in 2010, and it is still relevant today.
Plant Tissue pH = Energy By Bruce Tainio
While laboratory soil and tissue tests are good and necessary tools, we often don’t receive the results for several days, or even up to two weeks in some cases. On a growing crop, that can be too late. With this in mind, we developed a diagnosis of plant health based on liquid pH values of plant tissue sap, which has been used in our biological program at Tainio Technology & Technique since 1989.
Simple to use and 100 percent accurate, a quick plant tissue pH test is an instant snapshot of the state of health of any plant and can tell us the following information:
Enzymatic breakdown of carbohydrates (sugars) for proper growth and vitality of the plant.
Risk potential for insect damage.
Risk potential for foliage disease attack.
Nutritional balance in the growing crop.
Quality of nutrition in the fresh fruit or vegetable crop to be harvested.
Shelf storage potential of fresh fruits and vegetables.
The table below is a general guideline to determine what tissue pH means. With this scale we can predict the probability of insect and disease resistance or susceptibility.
The dictionary defines pH as “a number equal to the logarithm of the reciprocal of hydrogen ion concentration within a solution.” That’s a mouthful, but more simply put, pH represents the percentage of hydrogen ions in a solution. In our case, the solution is the liquid of the plant cell, or the sap.
It is important to know that a change in the pH level of a solution of just one unit equals a tenfold change in the hydrogen ion concentration. If the pH is increased or decreased by two units, the hydrogen ion concentration changes by a hundredfold! Thus we can see why what appears to be only a slight shift in pH can spell disaster for the farmer.
A neutral pH of 7 within the cell fluid means it contains 100 percent saturation of cations other than hydrogen (in other words, the sap contains no free hydrogen ions). At a plant’s ideal cellular fluid pH of 6.4, the saturation of cations other than hydrogen is about 88 percent. At 88 percent saturation – principally of calcium, magnesium, potassium and sodium – the ionization and activity of these elements generates an electrical frequency of between 7.5 and 32 Hertz, which is one of the “healthy” frequency ranges of all living cells.
To decrease cellular pH to 6.0 is to lower the saturation of the above four principle elements to 80 percent, thus lowering the plant’s frequency to a level of lower resistance to bacterial, fungal and viral plant pathogens.
Studies have shown that insects are attracted to a tree or plant by the tree or plant’s frequency. If the saturation of Ca, Mg, K and Na increases to over 88 percent saturation, the frequency from these ions in the cell are increased, and consequently, insects are attracted to the higher-than-normal cell frequency.
The same process occurs in animal and human cells. Hydrogen accumulation in the cell tissue means the saturation of Ca, Mg, K and Na is decreasing, thus causing the frequency to decline. This low frequency leaves the cell an easy target for disease.
Oftentimes we see both insect and disease problems occurring at the same time. This can happen when insects attack due to a high plant tissue pH, and the tissue becomes weakened in the localized areas of attack. Next, localized, rapid energy loss (a drop in pH) occurs at the insect-damaged spots, resulting in tissue disease attack of those areas on the plant.
When a pH shift of a half point (0.5) or more from the ideal 6.4 occurs in the cellular liquid, a laboratory tissue test should be taken to determine exact imbalances and which materials should be applied.
Tissue pH Rule of Thumb Low pH + Moderate Brix = Calcium Deficiency Low pH + Low Brix = Potassium Deficiency 6.4 pH + High Brix = Balance
In the interim, for a quick adjustment to bring up the pH, calcium can be foliar applied in small amounts per acre. To quickly bring down a pH that is too high, on the other hand, small amounts of phosphate can be applied to the foliage. These types of quick fixes are usually only temporary, however, and should only be used while awaiting a complete tissue test analysis.
Like most busy people, we have neither the time nor the patience to puree the two pounds of plant tissue it takes to get enough for a conventional pH meter readings; so we use the Cardy Twin drop pH tester, made by Horiba. With this pH meter, a reading can be taken out in the field in less than one minute. We just take a few leaves, roll them up into a tight ball, and squeeze out a few drops of sap using a garlic press. Be sure and use a good quality stainless-steel press, as a cheaply made garlic press will break.
Generally, the more mature leaves on the plant will give the most accurate picture of the plant’s health, level of resistance or susceptibility to problems. Since the plant spends most of its energy supporting new growth, the pH of new leaves will not reflect the pH of the rest of the plant as a whole.
pH & SUGAR
An indirect method of determining the energy levels of a plant is to measure the carbohydrate (sugar) levels in the cell liquid. For this test, a refractometer is used to determine the level of sucrose in the cellular fluid. This reading is referred to as the brix scale.
Within a given species of plant, the crop with the higher refractive index will have a higher sugar content, a higher mineral content, a higher protein content and a greater density. This adds up to sweeter-tasting, more nutritious food with a lower nitrate and water content and better storage characteristics. Such produce will generate more alcohol from fermented sugars and be more resistant to insects, reducing the need for insecticides. Crops with higher sugar contents will also have a lower freezing point and therefore be less prone to frost damage. Soil fertility needs can also be ascertained from this reading.
The brix levels should not be taken as an exact measurement of a plant’s vitality, but rather as a guideline. Stored sugar is not a cellular energy source until its carbon-hydrogen-oxygen molecular links are enzymatically broken apart. If this line breaks or energy release occurs faster than the cell can use it, then that energy is lost into the air. This condition usually occurs when the liquid pH of the cell is below 6.4 and most often indicates low Ca and high K.
The reverse can also occur – if the links between the carbon, hydrogen and oxygen molecules of a sugar are broken too slowly due to low enzyme activity, the plant becomes starved for the energy it needs for growth. This is usually caused by low manganese or zinc, or from high nitrogen/high tissue pH levels, coupled with drought stress.
As a general rule, we can say that when a plant has a low tissue pH and a moderate brix level, there is usually a calcium deficiency involved. On the other hand, a low pH with a low brix level usually indicates a potassium deficiency. The ultimate goal is to achieve a pH of 6.4 with a high brix level.
Plant tissue pH management is a relatively small but invaluable investment of your time and budget, which cannot only help you prevent disease or insect attacks, it can stop them in their tracks even once they have gotten started. This means better yields, bigger profits and most importantly, less need for chemicals.
When leaf temperature becomes too warm, plants switch from photosynthesis dominant to photo-respiration dominant, and begin ‘consuming themselves’.
The threshold for C3 photosynthetic pathway plants is a leaf temperature of 78 degrees Fahrenheit (25.5 C). For C4 plants, the threshold is 86 degrees Fahrenheit (30C) leaf temperature.
Leaf temperature and air temperature are not the same. The healthier plants become, the better they are at cooling themselves. There are several mechanisms in play, topics for future blog posts. It is clear that plants with a waxy sheen on the leaf surface can have a leaf temperature as much as 8-10 degrees cooler than plants that lack nutritional integrity in the same climactic conditions.
When this threshold is crossed and photo-respiration becomes the dominant process, a few important shifts occur:
photosynthesis/sugar production drops or stops completely
plants consume the limited available sugar supply
plants consume any free/available lipids as an energy source (these are abundant in high energy plants, very low in plants getting nutrition from soluble ions instead of from living microbes.)
once the supply of available sugars and lipids has been used as, plants begin consuming their own proteins as an energy source.
80% of the nitrogen (proteins) contained in plants is in the form of enzymes. Breaking these down further weakens the plants ability to recover quickly. Protein catabolism also leads to the formation of ammonium, which is a requirement for spider mite infections.
When plants experience periods of high heat stress, one of the best management strategies is to provide them with a surplus of energy in the form of sugars, oils, and sometimes proteins, to avoid the stress consequences of catabolism.
Foliar applications of sugars and sometimes vegetable oils can produce a tremendous crop response. In the past several weeks heat stress period, growers have reported some remarkable crop responses within 24 hours from foliar applications, both when applied proactively as a preventative, and during and after the heat stress. Rejuvenate inclusion in the foliar mix seems to consistently deliver clear visual results.
In a recent podcast interview with John Fagan we discussed the exciting possibilities of non-targeted lab analysis, which is relatively new development, permitting a wide scan to find what compounds might be present, without know exactly what we are looking for in advance.
At the conclusion of our discussion, I asked for John’s perspective on the oft-reported challenges of glyphosate, as he was a leader in developing the more recent assays which have greatly reduced the detection limits. In our discussion, I asked for some of the citations he was referring to. You can read John’s comments and descriptions in the first two documents listed below.
I do not consider it useful to constantly focus on possible negatives like glyphosate. I much prefer to focus on solutions and developing better outcomes. On the other hand, we do need to understand some of the limitations we might be imposing on ourselves, which is why we are posting this.
There are a number of people working on alternate technologies to replace the need for herbicides in general and glyphosate in particular. I wrote a post about the use of boric acid, and several growers have reported very good success.
When asked if they know how to plant nutrients become available to plant roots, producer’s answers typically include the belief that fertilizer must be added to the soil, where the fertilizer dissolves in soil water and the plants take the nutrients in. In fact, 90% of the nutrients taken up by plant roots are cycled through a soil organism before becoming plant available. Virtually everything plants need is supplied by the soil organisms that live in collaboration with each living plant.1 Less than a third of the nitrogen fertilizer applied to a field ends up in the plants grown there.2 The rest is retained by some other form of life in the soil, volatizes into the atmosphere, runs off the field or leeches down below the root zone of the soil with the movement of water. Most analytical soil testing and fertilizer prescriptions are based on the response in crop production of plants grown in dysfunctional soils. The methods and prescriptions work quite well; for dysfunctional soils.3 This should come as no surprise, since most agricultural soils in the U.S. do not cycle nutrients very well, so the corresponding methods of testing and prescribing fertilizer application have evolved accordingly.
Water infiltration and nutrient cycling are just two basic examples of what we now understand are processes that are driven by the organisms living in the soil. This change in understanding of how the soil works as a biological system is a major paradigm shift for almost everyone in agriculture. Armed with this new understanding of soil function, producers can reduce and eliminate the symptoms of erosion, runoff, nutrient leaching, drought, and poor crop performance to become truly sustainable.
The bottom line is that the plant available water in the soil becomes plant available because soil microorganisms made the soil aggregates that allow the water to infiltrate and be stored in the soil. It is also soil microorganisms that cycle and make the vast majority of nutrients available to plants.
If asked, any producer will tell you that they expect their soil to grow profitable crops by supplying water and nutrients to their crops. What many folks don’t realize is that these two basic expectations of soil function (water and nutrient supply) are biologically driven. Keep the soil microorganisms happy and the system runs at peak efficiency. A more efficient system will be a more profitable system.
We have known how to prevent and reverse plant diseases with nutrition management for a long time. The information is not new, it has just been ignored or forgotten.
Fertilizers and trace minerals can be used to increase disease severity, or to reduce or eliminate disease entirely. Many fertilization practices today are known to increase disease. This knowledge should be foundational for every farmer and agronomist, but has largely been forgotten. Perhaps because it would eliminate the need for fungicide applications?
A large volume of literature is available on disease control affects provided by macro- and microelement amendments. Huber and Watson in 1974 in “Nitrogen Form and Plant Disease” reviewed and discussed the effects of nitrogen and/or nitrogen form on seedling disease, root rots, cortical diseases, vascular wilts, foliar diseases and others. They summarized work from the 259 references in four tables in which they list crops, diseases and citations. McNew in the 1953 USDA Yearbook of Agriculture discussed effects of fertilizers on soilborne diseases and their control. He reviewed briefly specific diseases such as take-all of wheat, Texas root rot, Fusarium wilt of cotton, club root of crucifers and common scab of potato. Many other diseases were mentioned, as well as how macro- and microelements effect host physiology and disease. Huber and Arny in “Interactions of Potassium with Plant Disease” summarized in three tables the effect of K (positive, negative, neutral) on specific diseases. They listed 267 references in the bibliography.
The Potash and Phosphate Institute is dedicated to research and education and celebrated his 50th anniversary in 1985. It is a source of information on the use of K and P in the production of plants and the effects on plant disease. The Institute promotes a systems approach to crop production; disease control is one of the factors in the system.
Leath and Ratcliffe described plant nutrition and diseases in forage crops production. They indicated that fertilizers affect pathogens in the soil and on the host, and also can affect the pathogenicity of an organism. Presley and Bird reviewed the effect of P on the reduction of disease susceptibility of cotton.
Another review by Huber entitled, “The Use of Fertilizers and Organic Amendments in the Control of Plant Disease” contains a wealth of information. He indicated how the severity of 157 diseases was affected by N in table 1. In table 2, a similar listing is given for nitrate and ammonium forms of N. The effects of P, K, Ca and Mg are given in tables 3, 4, 5 and 6 respectively. Tables for S, Na, Mn, Fe, Zn, B, Cu, Si and other elements are also presented.
A literature research of the CAB ABSTRACT database utilizing the DIALOG Information Retrieval Service and using some keywords: soilborne disease, macroelements, microelements, soil fungi, Fusarium, Pythium, and Phytophthora, yielded 1500 citations published during the past 14 years.
Obviously a virtual flood of literature is available regarding the effects of macro – and micro element soil amendments on the level of soilborne disease in plants. What is lacking is the correlation of the positive factors into integrated production systems. The biggest problem now is how to organize and comprehend the mountain of available and often conflicting data. We have entered an era in which computer-aided analysis and other sophisticated tools are needed to integrate information and develop systems approaches is to growing healthy, productive plants.
One of the most rewarding approaches for the successful reduction of soilborne diseases is the proper selection and utilization of macro- and microelements. Since virtually all commercially produced crops in the developed world are fertilized, it is extremely important to select macro- and microelements that decrease disease. This is an important and viable alternative or supplement to the use of pesticides which usually only gives partial disease control.
Remember, this was published in 1989. What other things have you heard about that deserve to be generally known, but aren’t?
We might ask the question, “What is the root cause that allows aphids to feed on this plant?”
When we pursue the wormhole of information needed to answer this question, we can develop a description of the carbohydrate profile within plant sap that aphids are dependent on. The carbohydrate profile changes dependent on the critical minerals plants require as enzyme co-factors to develop functional enzyme systems. The mineral profile is determined by the soil biology’s capacity to supply specific nutrients. These are layers of empowering answers which indicate the management tools needed to prevent aphids from becoming a problem. You can find my previous blog posts related to aphids here.
We might ask a similar question at a different level of thinking, “Why are aphids showing up in this ecosystem?”
When we ask questions at a different level, we arrive at very different answers. How are we managing the field ecosystem that allows the aphids to proliferate unchecked? When we have a continuous mono-crop of plants with an incomplete carbohydrate profile, it is a near-perfect environment for aphids to proliferate. We are supplying them with an abundant food source, and no habitat for their natural predators. When we spray an insecticide, we improve the environment for the aphids even more, because now we have removed all the predators, and weakened the plants even further.
A natural followup to the previous question is, “How can we manage the ecosystem differently so that aphids are no longer present?
Thanks to Klaas Martens for pointing me to Eric Brennan’s research on inter-planting sweet alyssum in lettuce and broccoli as a biological control for aphids. As I followed the wormhole of published research on biological control for aphids at an ecosystem level, I was pleased to discover that adding relatively few insectary plants per acre like sweet alyssum can attract enough hoverflies to provide complete control of aphids.
I estimate that additive intercropping with about 500 to 1000 alyssum transplants per acre, distributed throughout the field should provide sufficient pollen and nectar for hoverflies to control aphids in transplanted romaine lettuce. ~ Eric Brennan
This limited population of sweet alyssum has no negative impact on lettuce yields, and seems unlikely to have a negative impact on yields of other crops. Sweet alyssum can be direct seeded, and seed is inexpensive. This seems like an imminently practical and scalable solution for other crops with aphid pressure.
What other practices or plants provide control of different diseases and insects? This is a topic I am would like to learn more about.
Prior to the human genome project, the popular expectation was that understanding the structure of DNA, and being able to edit or manipulate it’s structure would enable us remove the cause of degenerative illness.
As this project approached it’s concluding stages, it became obvious that DNA did not contain enough information to describe all the variability found within a given population. From this insight emerged the concepts of genetic fluidity and the science of epigenetics.
Epigenetics is the study of heritable changes in gene expression that do not involve changes to the underlying DNA sequence — a change in phenotype without a change in genotype. A foundational premise of epigenetics is that changes in environment result in changes of how an organism expresses itself.
“Heredity is nothing more than stored environment.” Luther Burbank
As farmers, we recognize this as an obvious truth. We know that we can plant the same seed in different fields with different soil types, and the crop will express itself differently. This effect is compounded as multiple generations are grown in different environments.
It is easy to recognize this process in plants, and also in animals.
We may not have appreciated enough how fundamental this process is in determining the pathogenicity or infectious capacity for the organisms we call ‘diseases’ or ‘pests’.
When we plant a blueberry plant into soil that is optimally balanced for alfalfa, we have placed it in an environment where it is unlikely to do well.
If we were to plant lambsquarter seeds into forest soil that is undisturbed, they will not even germinate, because they are not in the proper environment.
If we were to plant foxtail seeds into soil that is aggregated and well aerated, they also will not germinate, because they are not in the right environment.
Each of these examples is a case where the environment has determined genetic expression.
Soils can contain fusarium populations that are able to cause disease, but instead develop a symbiotic relationship with the plant, when there is a healthy soil microbial environment present. The DNA of the fusarium remains unchanged, but it’s expression is completely different.
Aphids will die in minutes, and become ‘candied’ when the sugar profile within plant sap they are feeding on changes. A change in the environment determines whether they live or die.
Not all insects in a given population serve as a vector for viruses. If an individual insect benefited from an optimal diet and environment, it will resist viral infections and not spread viruses from one plant to another. (Disease resistance is as real for insects as plants or animals)
Powdery mildew infections can decimate one variety, and leave another variety in close proximity completely untouched. The powdery mildew organism is present in both varieties, but one variety does not present a hospitable environment, and the organism never expresses itself as a ‘disease’.
We could continue this list until we included every ‘disease’ and ‘pest’ that is known.
The concluding point is simple: Every ‘pest’ requires a certain environment to be able to express itself. Change the environment, and the ‘pest’ ceases to be a problem.
If our crops are susceptible to disease or insects, it is because of our management practices that have created a hospitable environment. Change the environment with nutrition and microbial management, and you change the susceptibility.
The soil health challenges of glyphosate use are becoming well known. Don Huber has reported that even a single application of ten ounces per acre is enough to alter the microbial community in favor of oxidizing – disease enhancing organisms.
I am not aware that any other herbicide is known to have the strong antibiotic effect of glyphosate, though each has it’s own set of environmental and public health challenges.
Some growers have figured out how to eliminate herbicides altogether. Other growers are still on the pathway of figuring it out.
Robotic weed control technologies are being developed that may make herbicides obsolete in the future, but they are not here yet.
Given this state of affairs, it would seem wise to figure out how we can apply the smallest amount of active ingredient possible and maintain or improve effectiveness.
When we describe designing nutrition applications, we find that we get the greatest performance when we use synergistic stacks of products from different categories, for example: bacterial inoculant, fungal inoculant, microbial stimulant, microbial food source, plant nutrients, plant stimulants.
We can use this same concept to reduce the required rates of herbicides. Some growers have reported reducing rates by upwards of 80% and maintaining effectiveness using a combination of different strategies.
The practices which are known to improve herbicide performance include:
removing all minerals from the water, particularly carbonate and bicarbonate
acidifying the water
premixing the herbicide with a vegetable oil
adding sugar to the spray solution
adding fulvic acid to the spray solution
structuring the water
Each of these practices increases the effectiveness of any material added to a spray solution (including foliar sprays). When we stack practices together, the improvement in results can compound.
When we stack these practices together, they need to be added in the right sequence, much the same as products should be added to a spray tank in the correct sequence. Here is the sequence that I have observed to be the most successful:
Demineralizing the water, most commonly using reverse osmosis (RO). RO is very inexpensive for the reduction in active ingredients it can produce. This step alone can account for a reduction of 30-40% in product required.
Structuring the water after it has been through an RO device and demineralized.
Premixing the herbicide with vegetable oil 50/50 on a volume basis, and then add to the tank. The theory is that coating the compounds with vegetable oil will improve their absorption by the crop. I have some question marks about how this might work, and how much it actually does, but growers are reporting observable improvements.
Add any acidifying agents to tank, such as ammonium sulfate. This may require much less than you expect when you use RO water to reach a low pH.
Add fulvic acid to improve leaf absorption.
Add sugar to contribute stickiness, and improve leaf absorption.
Exercise caution when using this approach with selective herbicides. The applied products will be much more effective, and can easily damage the non-target species. Test how much application rates need to be reduced, they will almost certainly need to be reduced to avoid burn.
I have observed complete weed control with 8 ounces of RoundUp per acre, roughly 4 ounces of active ingredient glyphosate per acre.
What practices have you used to reduce application rates while improving effectiveness?
Farming is about taking three free things – sunshine, water, carbon dioxide, running them through a catalyst called soil, and producing things to sell. ~ Ben Taylor-Davies
The magic of photosynthesis is that it takes abundant free resources we can’t otherwise easily capture, creates incredible ecosystems that sustain millions of organisms, which are used as food, clothing, and housing. Photosynthesis is the source engine that drives everything else.
Photosynthesis is the only way to bring new energy into the ecosystem. It makes sense to optimize the efficiency of this photosynthetic engine as much as possible, particularly when we consider that modern agriculture commonly realizes only 15-20% of an average crops photosynthetic potential. This means our use of these free resources is only 15%-20% of where it might be.
We choose to pass up these free inputs whenever we use products or management practices that limit photosynthesis and soil microbial activity, restricting carbon cycling.
Modern agronomy does not emphasize capitalizing on the things we are given for free, instead focusing on the supposed need to buy more things which are not free. Not free to the farmer, and expensive to the environment.
Contemplating additional inputs which may or may not be free –
Does nitrogen qualify? The air is 78% nitrogen, and vigorous healthy microbial populations have been measured supplying 300 units of N per acre with no legumes and no manure applications. Is biological nitrogen free? If not entirely free, it certainly costs only a fraction to grow as compared to buying it, both to the farmer, and to the environment.
What about soil minerals? Are they really free? What is the true value of soils that contain more phosphorus, potassium, calcium, and trace minerals than will be used by crops for centuries or millennia? Should we account for the additional value of soil’s mineral and humus fertility on our balance sheets when we improve it? Should we account for investments in regenerating soil fertility as an operating expense, or as a capital improvement? And most importantly, how expensive are purchased inputs that prevent us from accessing these resources in our soils?
What about the free consulting advice of sales agronomists who advocate the continued use growing practices and products which limit the potential of the ecosystem to tap in to these free inputs? How much does ‘free’ advice actually cost?
What do you think is perceived as free that actually isn’t?
What other things do you think are free that we are not considering or optimizing for?