Picky-Eater Insects Pass On High Brix Plants

By Thomas M. Dykstra
This article also appears in the September 2019 issue of Acres U.S.A.

For many decades now, the magic number of 12, in regards to leaf Brix, has been tossed around as the number to achieve if desiring to prevent insect pests from attacking your crop plants. Although not entirely accurate, this is a good point from which to begin a discussion.

This is not an article discussing Brix refractometers, how to use them, how to read them, or even how to argue the merits of digital versus analog refractometers. I will assume that the reader is familiar enough with their use. But for those who are hoping to garner some additional talking points above and beyond the magical value of 12 Brix, then I believe this short article can help.

Although refractometers are commonly used in the wine and citrus industries for testing grape and orange fruit sap, the notion of taking Brix readings from leaves finds more restricted uses among agricultural consultants and farmers in the know. Sometimes this is referred to as leaf Brix in order to differentiate it from the more common usage of testing sap from fruit. The Brix charts circulating around the internet include both leaf and fruit Brix, so I need to be clear that my discussion will focus on leaf Brix measurements.

Insects and Brix

First of all, one must understand at some level that insects do not attack healthy plants. Many people know this instinctively, but few have been told this explicitly. It is for this reason that knowing your leaf Brix levels is crucial to knowing your crop, whatever you may be growing. High Brix (14 and above) means not just that insects will not attack a given plant but that they will not even be attracted to the plant. In short, pest insects will pass over a high Brix field.

The converse is also true. Insects are very attracted to low Brix plants (6 and below). Unfortunately, if one uses insecticides to keep insects off plants, then it takes longer to realize this truth due to the insect indicators being repelled or killed. If you leave the insects alone, they will indicate to you the relative health of your plant. Now a logical, and seemingly heretical, conclusion to be drawn from this is that insecticides are totally unnecessary for protecting high-Brix plants. Financially speaking, excessive inputs reduce profit. Eliminating insecticides will increase a farmer’s profit — this should be your goal.

But if the only important Brix value to know is “12,” then what exactly is the purpose of having the other numbers? What types of information can be gleaned from Brix values of fourteen, or nine, or even five? For those who want to know something about their crop — immediately, right there on the spot — without having to send a sample away to some far-off laboratory, then you should be Brix-testing on your farm.

Leaf Brix measurements

The vast majority of leaf Brix measurements will fall between 0 and 20. Therefore, I will restrict my analysis to those numbers (see chart – coming soon). The leaf Brix chart I have constructed is broken down into both general categories as well as more specific levels. The general categories include (1) those plants between 0 and 2 Brix, (2) those between 3 and 7 Brix, (3) those between 8 and 11 Brix, and finally (4) those between 12 and 20 Brix.

Low Brix plants: 0-2

Generally speaking, if a full-grown plant falls between 0 and 2 Brix, it already has one root in the grave. Plants with Brix readings that low are removed from planet Earth with alarming efficiency. Insects will move in quickly to consume these plants and disease will run rampant in these plants since they essentially have no immune system. These plants are unable to take care of themselves in a natural environment. If grown in an artificial environment, then they must be “spoon-fed” in order to survive.

For those who have ever played golf (not miniature golf), you have most likely walked on plants in this Brix range. Turfgrass cut that short, especially on the greens, has very little ability to effectively photosynthesize. Also, the prodigious amounts of pesticides sprayed on this same turfgrass through the sprinkler systems will indirectly prevent substantial root growth, making it difficult for the plant to store nutrients. If not continuously fed and watered, turf below 2 Brix will turn brown in a matter of days. Diverse insect groups will be attracted to it and will assist in the very natural demise. Spraying insecticides helps to hide the insect presence, and daily watering with synthetic fertilizers will be just enough to keep the turfgrass alive for one more day. These plants are being spoon-fed; their existence depends on it.

Mid-level Brix plants: 3-7

The next general category is substantially different. Those plants with leaf Brix readings between 3 and 7 have a fighting chance at survival. Many of our crop plants are between 3 and 7 Brix and are in considerably better condition than plants below 2 Brix. These plants require neither a daily dose of pesticide nor a daily dose of fertilizer. A farmer may only spray weekly or even biweekly, depending on the leaf Brix values, in order keep the crop alive. Most of the agricultural plants I have tested — perhaps 75 percent of them — fall within this range.

To be sure, these plants are struggling. They have enough inherent ability to get by and can even provide for their own basic needs, such as the production and storage of sugars. But they will not thrive. Size, health and yield will all be compromised.

Once most plants reach 6 Brix, there is a significant jump in the production of secondary plant metabolites. Secondary plant metabolistes are the phytochemicals that help contribute to a plant’s odor, color and taste. In addition, some secondary plant metabolites provide natural plant defenses against pests. These 6-Brix plants are finally able to devote their energy reserves into producing new proteins and diverse molecules. At 5 Brix and below, plants produce tasteless leaves, exhibit dull coloration and boast fruit with minimal odor signatures. For example, if you hold a tomato in the supermarket or out in the field and cannot detect any odor emanating from it, then that is a preliminary sign that it may be below 6 Brix.

Higher Brix plants: 8+

Once a plant reaches a leaf Brix of 8, the secondary plant metabolites have really started to kick in and natural resistance begins. In my experience, Homopterous insects, such as aphids and scales, lose interest in the plant that obtains a value of 8 Brix. In fact, it is relatively common for me to spot these insects on plants below 6 Brix. When a plant reaches 8 Brix, the aphids lose interest, but other insects can and will move in to feed on the plant.

In certain circumstances, the presence of aphids can be an indication that only a part of the plant is below 8 Brix. Diseases characterized by physical “plugs” that prevent the flow of nutrients through phloem and xylem tissue are often manifested in trees by dead or dying branches. Insects will focus their feeding on these weakened branches and ignore nearby branches with seemingly healthy leaves and/or stems. It is for this reason that different parts of the same citrus tree can display different leaf Brix readings when Citrus Greening takes hold, and even more so during drought conditions, when plugging of the vascular tissue is prevalent.

When plants ascend the leaf Brix ladder and reach between 8 and 11 Brix, insects metaphorically “fall off” the plant because the plant has a “sword and shield” that protects itself from insect predators. As a general rule, and although exceptions occur, sucking insects will not tolerate 8 Brix or higher. Chewing insects that eat the roots or leaves directly, such as caterpillars, grasshoppers, and beetles, will start to lose interest in eating a plant once the plant reaches 10 or 11 Brix.

I have witnessed grasshoppers taking bites out of 12-Brix leaves and then flying off the plant. I have also witnessed immature caterpillars of the Fall Webworm stop eating the leaves of a pecan tree once the Brix is increased to 12. As a result, these caterpillars will form a dense clump and then slowly die of starvation within inches of healthy growing pecan leaves. Virtually no insects will attack a plant at 12 Brix; this is why this figure is tossed around so commonly among growers.

Now variability is a hallmark of Nature. Fluctuations between Brix readings can and do occur throughout a growing season. Even if maintaining Brix levels in a given crop, it is not unusual for the leaves to fluctuate 1-2 Brix from one week to the next. It is for this reason that the safest place for your plants to be is at 14 Brix or above. In this way, one may be relatively secure that natural fluctuations do not take your crop below 12 Brix where it may become differentially attractive to various insect pests.

The role of sugar in Brix levels

Although Brix is a measurement of dissolved solids, for our purposes it is the measure of sugar in plant sap. Sugar is the main product of photosynthesis. The more a plant photosynthesizes, the more sugar is contained in its tissues, and the higher the leaf Brix readings. This sugar is produced in the leaves, and is not only stored in the leaves but eventually descends to the roots as well.

Depending on environmental conditions and the health of the plant, approximately 20-70 percent of the sugar (photosynthate) is expelled into the soil from the roots. This expelled sugar feeds the microbes that will, in turn, break down minerals and supply them to the plant. Therefore, high Brix plants will support a thriving subculture of microbes in the soil.

But sugar has another role. It is hygroscopic, meaning that it absorbs water. It may accomplish this by absorbing liquid water, such as from a spill, or by absorbing water vapor from the atmosphere, which can occur under conditions of high humidity. Either way, the more sugar you have in the soil, the higher the soil’s water retention. Hence, drought resistance and high-Brix plants go hand-in-hand.

Plants with a Brix of 4 might only contribute 25 percent of their photosynthate to the soil, but plants of 10 Brix may provide the soil with 40-50 percent of its photosynthate sugar and still have enough sugar to grow reasonably well.

By the time a plant reaches 14 Brix, there is so much sugar being pumped into the ground from the crop that microbial counts can reach 20 million or higher in a teaspoon of soil. On top of the soil, these plants are not only drought resistant, but freeze tolerant as well, since highly concentrated sugar water will not freeze above 26 F. Freeze warnings from the National Weather Service then become largely inconsequential to a grower.

Brix levels and our health

Insects have a simple digestive system and cannot digest the same foods that we do. Low-Brix plants are designed for the insect gut. They do not have the digestive enzymes to break down healthy proteins from high-Brix plants, only the broken or incomplete proteins from low-Brix plants.

High-Brix plants are meant for vertebrate animals, most notably humans. When we eat healthy plants, we augment our long-term health. When we eat low Brix plants, our long-term health is compromised, although the effects may take years to manifest.

Therefore, we should be eating high-Brix food for our long-term health. If eating meat, then our animals should be feeding on high-Brix plants. If continuously fed low-Brix plants, our cows, our sheep, our goats and the like will display compromised health and will suffer from various diseases and spontaneous miscarriages. It is only common sense to say that eating this unhealthy meat will then, in turn, compromise our own health.

Brix fluctuations and other considerations

It is important to repeat that this article refers to leaf Brix only. There are other parts of the plant, such as the fruit and the roots, that often display different Brix readings when compared to the leaves. This is to be expected. But roots are hard to get to and measure. Additionally, testing roots is often destructive to an individual crop plant. Testing leaves is not only easier, but is more consistent.

There are uncomfortably large fluctuations in both root Brix and fruit Brix readings throughout the season that make both of them difficult to decipher without the help of a specialist. Unless someone is very familiar with the differential readings from differing plant tissues, a farmer should stick with leaf Brix first and foremost as the chief indicator. Comparatively speaking, leaf Brix measurements remain much more consistent; hence, they are the gold standard when determining the relative health of your crop.

Insects recognize Brix levels better than we do. Insects are indicators. They indicate to us what plants are unhealthy to eat. If a codling moth caterpillar is in my apple, I am going to toss the apple. It is not worth eating. The insect has told me this by virtue of its presence. On the other hand, if insects are not present and no insecticides are being sprayed on the crop, thus allowing insects to choose, then this would be an indication to me that the crop may be healthy for my family to eat.

For those who are actively testing their crops with a Brix refractometer or have an agricultural consultant who is accomplishing the same, much information can be gleaned within just a few minutes about the current state of your crop. To be sure, there is more information that can be provided with further off-farm testing, at considerably greater expense. But in terms of an on-farm testing procedure, using a Brix refractometer is an inexpensive first step, and a wonderful one at that.

Tom Dykstra is an agricultural consultant based in Gainesville, Florida.

Falcons for Bird Abatement

By Tara Maxwell

Falcons are a predator of feathered farmyard dwellers, but they can be put to positive use on the farm. When it comes to employing creative solutions for naturally protecting crops on organic farms, perhaps the sky really is the limit. Duncan Family Farms, an organic grower located in Goodyear, Arizona, specializing in baby greens, kale, beets, chard and herbs is using an innovative method for bird abatement: falconry.

Duncan Family Farms has been working with Falcon Force since fall of 2016, according to Specialty Crop Manager Patty Emmert. Falcon Force has been practicing nuisance bird abatement for six years and operates in five states. Their clients include farms, orchards, vineyards, resorts and airports. Falcon Force uses the predator/prey relationship to eliminate pest birds, which can cause millions of dollars in damages. Falcon Force uses a team of trained falcons to intimidate and scare off nuisance birds such as the horned larks and pigeons that frequent the area.

For nearly all vegetable growers, small birds can present a big challenge — they not only eat seeds after they’ve been planted, but can also shed feathers or defecate in the fields, triggering additional food safety measures. Previously, Duncan Family Farms had staff walk the fields with shakers or slings to scare birds away, but the birds got accustomed to the noise and presence of people, becoming progressively harder to chase off.

Duncan Family Farms is a family-owned, multi-regional grower of more than 8,000 acres of certified organic produce. Founded in 1985 by Arnott and Kathleen Duncan, the company is one of the largest growers of organic produce, nationally recognized for their farming techniques and premium-quality food for processors, retail and foodservice distributors.

A falcon takes flight at Duncan Family Farms.

As an organic grower committed to sustainability, Duncan Family Farms was motivated to find an effective solution that eschewed the use of traditional approaches such as flares, firecrackers, or Mylar, all of which are harmful to the environment and have the potential to leave debris in the fields and cause product losses. These methods are also not an effective long-term option because birds get used to them.

Falcons: A Force for Good

Falcon Force uses the natural predator/prey relationship to deter nuisance birds long-term — their main goal is to chase the nuisance birds away. Once a horned lark sees one of its natural predators flying and swooping nearby, it’s going to immediately find a safer place to forage for food. An additional benefit of the trained falcons flying in the fields is that native predator birds will also leave the area to find new hunting ground, meaning they are less likely to kill a prey bird in the field.

“It’s pretty amazing to see the results — we can actually watch the nuisance birds leave the area and not come back,” said Jeremy Vanderzyl, technical services manager at Duncan Family Farms. “A single falcon can cover a large area effectively and efficiently and allows us to avoid putting our personnel in uncomfortable or potentially unsafe conditions.”

kalen pearson
Kalen Pearson of Falcon Force at Duncan Family Farms.

Falcon Force was at Duncan Family Farms in Goodyear through the end of April, and the farm has plans to continue the relationship at other growing locations with different bird abatement challenges such as large migratory birds like ducks and geese.

“It’s immediate, it’s sustainable, it’s organic and it’s biodynamically perfect,” said Kalen Pearson of Falcon Force. “Birds are always going to be afraid of other birds; it’s never something they’re going to get used to like a scarecrow or noisemaker.”

Pearson, a member of Falcon Force’s abatement team, began her journey into falconry at the age of 19, flying gyrfalcons and peregrine falcons. A few years later she began a career as a professional falconer. Each abatement team member has her own crew of raptors that they have extensively trained and are currently working with.

Tara Maxwell is managing editor of Acres U.S.A. magazine. She is a graduate of Virginia Tech with a background in journalism and animal science and a passion for sustainable farming.

Barn Owls for Pest Control

By Anita B. Stone

Using barn owls for natural rodent control is gaining traction among farmers and those in other agricultural sectors. This has come about from increasingly critical environmental issues regarding chemical use in the field for rodent population control. To reduce poisons and other invasive methods of pest management, one of the most beneficial owls on the planet is being called upon as an expert rodent assailant.

Barn owls are noted for being fond of nesting but the lack of nest sites, including the loss of tree habitats, has become a major reason for the decline and non-productivity of this owl species.

When hole-nesters cannot find suitable places to breed, the population decreases notably.

Farmers have been putting barn owls on patrol for prey, including moles and gophers, as part of an Integrated Pest Management (IPM) alternative.

barn owls

Barn owls exhibit some of the best hearing among birds of prey. They have a white heart-shaped, monkey-faced appearance, and are distinguished by whitish or pale cinnamon underparts and rust-colored upper plumage. Velvety feathers allow them to approach their prey silently in darkness.

Recognizable barn owl sounds range from soft chirps to a long raspy screech. If alarmed, they emit a violent hiss and are even known to hoot every now and then.

The average barn owl weighs about one pound and is about 15 inches long with a wingspan of approximately 40 inches.

Home Sweet Home

Because barn owls don’t build nests of their own, artificial nest sites are a positive way to increase their population. Ideally, if everyone assists the accelerated loss by building owl boxes, the raptors will have a safe place to nest.

Barn owl nest boxes are relatively easy to construct. Except for hole size and placement, the dimensions of the owl house are not critical. There is no limit to the number of boxes that can be constructed and hung across the field or landscape, which is preferable.

Most barn owls are migratory, but some remain year-round. Known as cavity dwellers, barn owls will inhabit tree cavities, crevices between palm tree fronds or small caves in cliffs or banks. So long as they have a cavity which is snug and quiet, 10 feet or more off the ground, these raptors will be satisfied. Some have even been found in barrels, steel drums, cat litter boxes or between bales of hay. With a shortage of nesting locations available, they will be happy with as much assistance as farmers can offer. Owls will move into any cozy place they think is right for them. But the best home is the nesting box. If you find owls nesting in your hayloft or rafter, chances are they will probably stay there.

These owls will tolerate noise and commotion around their nest, as long as they are not threatened and the food supply remains constant. They have been known to return to their nesting boxes season after season.

The North American Barn Owl species inhabits open areas and is considered rare in several states, endangered in other states and requires new areas due to rapid urbanization and the technological development of agriculture.

Owls may have different mates during subsequent mating seasons. The female lays from one to 11 white eggs between November and July, and incubation is about 30 days. One to two broods are reared during the season with the young leaving the nest about eight weeks after birth.

Plans courtesy of USDA

Because barn owls are not known to have major territorial instincts, and will nest just about anywhere, the placement of owl boxes should serve the farmer’s need as well as the needs of the owl.

It is best to place the boxes in an area with little human activity, facing the box opening away from any prevailing winds. If a box is set on a post, it is best to be within 100 yards of a large tree to provide safety for the young.

One can build boxes that fit into existing barns or other farm buildings. Owls may already be living there and may be attracted to additional nesting sites. In a nest box, the babies require protection from falling and remain out of sight and therefore will be less likely to be fearful when anyone enters the building.

Another approach is to erect owl boxes either in or under trees adjacent to the rodent infested fields. While the owls are close enough to take advantage of the rodents in the fields, the young owls will be able to enjoy the safety net from the hot sun provided by the surrounding woodsy area, using the trees as refuge once they leave the nest.

Cats, opossums, raccoons, squirrels and great horned owls may prey upon both the young and adult barn owls if they are in the immediate area. A third method is to install the boxes in the fields where the food supply is found.

For example, you can install boxes at the end of produce rows on 16-foot 4 x 4s, buried 3. feet in the ground. The top of the box is set at the top of the post, leaving the bottom of the box at almost 11 feet.

There is no guideline for farmers and growers as to how many boxes per acre will be required. The bottom line is that it depends on how many gophers, rats and raccoons you want to get rid of.

It is recommended to space the boxes around any rodent infested areas, figuring about four to six for every 50 acres.

If rodents are not devastating a field or crop the same number of boxes will work for 100 acres.

Simply make sure to provide adequate sites. We need to remind ourselves that, unlike many species, barn owls do not build nests — they simply lay eggs in holes, including rotted trees, rocky cliffs or bluffs. But it’s always positive to build a nesting box and establish perching sites for them. Good locations are wooded areas or in open fields and meadows with a few trees.

Oak and sycamore are ideal tree selections. The box can face any direction and may be hung 3 feet below a stout tree limb suspended by cables or mounted on poles which are anywhere from 15 to 30 feet above the ground. Place about six boxes per square mile for a wide field. If you decide to place the box on a post, it is best to wrap the post with a metal, conical predator guard. The success rate of box inhabitation is about 50 percent.

Summer is the best time to erect a barn owl nest box. Boxes should not be disturbed during the nesting season or owls may desert them. Ideally, about 85 percent of barn owl nesting boxes produce fledging young. Reasons for mortality among this raptor include human interference, limb breakage and a variety of attacks by raccoons, bobcats, skunks and opossums.


Basic requirements for a man-made nest box include minimum dimensions of 12 inches x 12 inches for the first floor and a cavity depth of 16 inches. To keep out predators, including the great horned owls, the entrance should be approximately

5 to 6 inches in diameter and located near the floor of the box to provide availability for the young. Make vent holes to allow air circulation near the roof. Water drainage can be made by making holes in the floor, near the corners of the box.

Make sure you include a means of cleaning and inspecting the box regularly. Inspections should be done twice each year, in June and November. Once the last chick leaves in spring, remove the remains of any dead animals and old wood shavings. Disinfect the inside of the box with a solution of 2 percent household bleach sprayed into the box. In the fall, prior to the return of the adult owls for the breeding season, make sure that paper wasps or honeybees have not moved into the box since the owls left.

Within the design, you can also establish partitions, separating the entrance from the nesting area and protecting the eggs and babies from any predators.

If you want additional protection, a roosting room for the parents to perch during the day has about the same size opening as the main cavity. If you offer more room, the hen will lay more eggs. Nest box designs range from elaborate arrangements, complete with perches and insulation to simple one-room constructions. You can use scrap exterior grade three-eighths inch or one-half inch plywood and #4 or #5 galvanized hot dipped box nails. By painting the boxes a dull green, black or brown color, you will be helping to camouflage the owls’ home. Use a marine grade plastic resin or exterior wood glue to assemble the box. Make the roof 16 inches by 26 inches to give a 1-inch overhang all around. Painting also helps prevent wood warp. Place a 2-inch layer of sawdust or wood chips in the bottom of the box and replace this “flooring” each year.

When you are ready to hang the box, use at least a 9-foot piece of wire and raise the box from 15 to 30 feet above the ground. Perches for landing outside and roosting inside are optional but they will enable the young to stretch their wings and exercise before their first flight.

This article appeared in the December 2012 issue of Acres U.S.A. 

Understanding Insect Infrared Detection

By Philip S. Callahan, from the introduction of his book, Tuning In To Nature

Tuning in to Nature was written in 1975 as a direct result of an experience I had shortly after World War II ended, when I was still attached to the RAF Coastal Command in northern Ireland.

During July 1945, I took a Jeep from Belleek to Castle Archdale in Fermanagh County, northern Ireland. The RAF Coastal Command had its western Ireland headquarters on Lough Erne not far from our American Radio Range Station near Belleek.

When I picked up a technical report by the RAF on the XAF (10 cm radar) the researcher pointed out that most boat hulls were in sharp focus since 10 cm is a short wavelength in comparison to a boat. Diesel launches under way, however, were “blurred with indistinct edges over the stern.” It did not take long to deduce that the XAF radar was “seeing” the diesel exhaust — in short, the radar was smelling exhaust by electronics. This rather simple observation led to my irreversible belief that insect spines (sensilla) are indeed real antennae.

It was a few years later, after corresponding with Dr. Ernst Okress of American Standard Corp., that I knew for certain that insect antenna sensilla were dielectric, or plastic-like, antennae. That is the subject of Tuning in to Nature. In other words, insects utilize frequencies, not scents, to find their way around in nature.

When radar picks up a ship or aircraft, as we all know, the beam bounces off the aircraft and reflects back to a receiver that plots time and space. The transmitter and receiver are usually a few feet apart so that the return path is separated by a small angle from the “out” path.

In phase conjugation, the opposite is true, as the return is by the same path as the emission path. In other words, it is like an ant trail; the photon “ants” come and go along the same pathway. A conjugate system adds up energy until it is many times stronger than a conventional beam. It is thus the radar gun that incinerates an aircraft.

I soon realized from these experiences that the components of a successful trap must be close together in order to obtain enough power to attract insects. That is exactly why small insects work so well, as do the small solid-state, man-made transistors — the components are close together and take advantage of phase conjugation.

Working for 30 years alone, with little help from other scientists, I have now developed a phase-conjugated insect trap (Patent No. 5,424,551 — Frequency Emitter for Control of Insects) that attracts by infrared wavelengths alone. A patent on the more efficient solid-state version, for use on stored grain insects, has recently been filed. It attracted, by infrared frequencies alone, 100% of released male Indian Meal Moths. Indian Meal Moths are said to destroy up to one-fifth of the world’s stored grain!

This solid-state trap is based on a knowledge of modern technology— radar. In particular on the concepts of phase conjugation. It is just as importantly based on the ancient knowledge of nature attained by the agriculturally-orientated farming pueblo Indians, in particular by the ancient Anasazi and the 19th-century Hopi Indians. Most of their astute knowledge of how nature works, as it was with myself, was based on observing the behavior of ants and ant communities in the desert. Lastly, it is based on the physics of the scent behavior of the ants in the hill.

None of these approaches are tolerated by modern entomologists. Computer guesswork and arrogance about how God designed things have been substituted for natural observations and for physical experimentation. Low physical energies and the connection of those electromagnetic energies to the atmosphere are rarely if ever considered.

Modern entomology fosters deadly poisons in place of observation of nature, and of experimentation utilizing the science of physics in the control of damaging insects.

The main ingredients of my work have been natural observation, respect for the Ancients, and prayer, all of which are unacceptable as methods of scientific research with our now sacred universities!

Early in my career, I studied pesticides, as did all entomologists. But the findings I released in this book, Tuning in to Nature, taught me that attempting to poison insects was at cross purposes to nature and would, in the end, prove futile.

Now, 25 years later, worldwide pesticide use is at an all-time high; crops lost to insect damage are also at an all-time high. As I witness our cancer epidemic, I take no joy in having been “right.”

A sick plant actually sends forth a beacon, carried in the infrared, attracting insects. It is then the insect’s role to dispose of this plant deemed unfit for life by nature. By learning how to “tune in to nature,” may you learn to better understand God’s beautiful design and come to work with nature by enhancing her energies, rather than attempting to overpower and rule over her.

About the Author

Philip S. Callahan was born on August 29, 1923, at Fort Benning, Georgia. He entered the U.S. Army Air Force, San Antonio, Texas, in 1942, and served two years in the European Theater of Operations during World War II. Hiking around the world after the war, he worked as a freelance photographer and writer.

On his return to the United States he matriculated at Fordham University New York, New York. He received his B.A. and M.S. degree from the University of Arkansas and his Ph.D. from Kansas State University. He joined the staff of the Entomology Department at Louisiana State University in March 1956 as Assistant Professor. He was promoted to Associate Professor in 1959. He joined the U.S. Department of Agriculture, in Southern Grain Insects Research Laboratory, Tifton, Georgia, in July 1962 as Project Leader for insect biophysics. He was also Professor of Entomology on the Graduate Faculty of the University of Georgia.

In 1966, he received the Superior Service Award of the U.S. Department of Agriculture from the Secretary of Agriculture. He also received the annual award for distinguished research from the University of Georgia, Chapter of Sigma Xi and also the Sears Roebuck Foundation Award for contributions to agriculture. In 1969, he transferred to the USDA Insect Attractant and Behavior Laboratory at Gainesville, Florida. He authored over 106 academic papers and 12 scientific books throughout his career. Dr. Callahan passed away in 2017.

Tuning In To Nature book
Tuning in to Nature by Philip S. Callahan

Non-toxic Insect Management

By Philip A. Wheeler and Ronald B. Ward

A soil system for energy and nutrient production is a living system in which bacteria and other soil organisms must receive nutrients and energy from proteins, carbohydrates, cellulose, lignins, all organic materials from a soil that has a managed supply of air and water within a balanced chemical environment.

This chemical balance involves more than simplistic N, P and K. It requires an equilibrium of pH, calcium, magnesium, sodium and potassium, humus and a nutritional balance of sulfur, with correct relationships of nitrogen to calcium, calcium to magnesium, etc. Many readers will recognize the above as an Albrecht conceptualization.

The authors of The Non-Toxic Farming Handbook seek to impart the above knowledge, in further detail, as well us related eco-farming knowledge, through the pages of their handbook. The excerpt below discusses the issue of insects, methods of control, and the connection with the soil.

As the professor Phil Callahan says, “No method of insect control will ever work as long as poisoned crops outgas ethanol and ammonia in small parts per million. Those two powerful fermentation chemicals are the mark of a dying, decaying plant and serve as attractants to all plant-eating insects.”

Read on below:

From Chapter 5: Insects

Insect Damage

Insects and insect damage have been called the “farmer’s curse.” It is true that each year millions of tons of produce, grains, and fruits are destroyed or damaged by insects. Insects account for a 13-16 percent loss from $244 billion in crops annually in the United States. Insect numbers count in the billions and their collective weight by far surpasses the collective weight of mammals. Of more than a million zoological life forms identified and categorized by scientists, more than 800,000 consist of insects. It is believed that as many as 10 million insects remain as yet to be identified. Aside from our annoyance with these pesty critters and their attacks upon crops, pets, and livestock, what is their purpose?

Insects actually benefit man. Estimates of the value of insect pollination from honey bees and wild bees alone amount to approximately $30 billion annually in the United States. Insects pollinate fruits, berries, grapes, and field crops including peas, onions, carrots, clover, alfalfa, and flowers. In addition, insects provide millions of dollars annually in the form of such items as honey, shellac, and silk.

Honey bee
Estimates of the value of insect pollination from honey bees and wild bees alone amount to approximately $30 billion annually in the United States.

Many insects are actually beneficial to man because they devour insects harmful to our crops. Ladybugs, for example, will eat aphids. These predators play a useful role in maintaining balance within the insect kingdom.

Less than 1 percent of the insect species are considered harmful. About 1,000 species are considered serious crop pests, another 30,000 species are described as minor crop pests. Their control cost is only slightly less than the value of the crops they would have destroyed if left alone. In 1995, worldwide expenditures for pesticides hit $37.7 billion; U.S. expenditures came in at $11.3 billion.

Conventional Control

Insecticides are the modern mode of insect control. Insecticides come in either dry or liquid form and are either dusted or sprayed. They are used to prevent insect damage as well as to kill the insects after they have arrived. Insecticides come in several types. Some are stomach poisons which react within the insect after being consumed. Others kill on contact. Others, called systemics, are absorbed by the plant or animal and affect the insect after it bites the treated host.

Insect pest on crop leaf
Once the variables influencing insect attack are understood, steps can be taken to remedy these causes

Now that public awareness has increased and public opinion has caused the EPA to review pesticides, it is expected that many will not be allowed to remain on the market. This scenario has prompted Steve Brown, Auburn University Extension Service, to list several alternatives for farmers to consider. These can be considered as part of an IPM or Integrated Pest Management program.

  • Select insect-resistant varieties.
  • Calculate closely such variables as planting dates and row spacing.
  • Take advantage of crop rotation benefits.
  • Utilize pheromones (insect sex attractants) to capture or disrupt insects or introduce predator insects.
  • Utilize the biological pesticides which are available.
  • Consider trap crops in certain instances.
  • Utilize plastic mulch.
  • Consider soil solarization, using clear plastic.
  • Utilize machinery which sucks insects off plants.

Although these suggestions represent creative solutions to a growing reality, they miss the mark in that they don’t address the cause for the insect infestation in the first place. Once the variables influencing insect attack are understood, steps can be taken to remedy these causes. Addressing the cause will produce more lasting results.

Infrared Signals

Dr. Philip Callahan, renowned authority on the corn earworm and author of The Soul of the Ghost Moth and numerous other books, has studied insects extensively in his role as USDA researcher. His research indicates that insects communicate via infrared signals which are received and sent by the insect antennae which occur over much of their bodies. Each insect is apparently sensitive to certain plant signals and ignores others. Most damaging insects are selective in what they attack. Thus, the alfalfa weevil would not infest elm trees.

Infrared signals are emitted naturally by all living plant or animal bodies as well as from the gaseous emissions of all plant and animal life. Signal strength and configuration are affected by a variety of factors including nutrient balance and stress factors. Insects detect these signals with their antennae.

Antennae of the male cecropia moth.
Antennae of the male cecropia moth. Insects, like this moth and others, can detect much information from plants via their antennae.

Upon close examination, it is evident that each species of insect has an antenna shape unique to its species. According to Dr. Callahan, the shape of the antenna determines the signal range received by the insect. Thus, the shape of weevil antenna allows it to be attracted to alfalfa frequencies.

When plants are grown in a soil with balanced nutrients and the plant itself utilizes those nutrients in a balanced manner, its own system will maximize its genetic potential in terms of yield and health (or resistance to stress). However, when the soil is out of balance, when normal growth stresses, e.g., drought, excess water, heat or cold, wind or hail occur, the plant may require other nutrients to counteract the stresses at hand. The extent those nutrients are missing is the extent the plant will suffer and, eventually, deviate from its genetic potential.

The infrared signals given off by the plant will modify depending upon the health of the plant. As the plant moves further from ideal health, the signals become more pronounced in a way that attracts insects. This can be shown by taking refractometer readings and observing that the brix reading measured as percent sucrose on attacked plants is lower than plants not being attacked. The brix reading is a good indication of the efficiency of the plants’ output of carbohydrates which is the result of photosynthesis.

Soil Balance-Imbalance

A properly balanced soil will have sufficient quantities of organically active carbon — humus — which helps hold nitrogen in the ammoniacal form. In soils lacking this active carbon content, the soil will give up this ammoniacal nitrogen to bacterial conversion into nitrates or directly to the atmosphere in gaseous form. During the process of ammoniacal nitrogen leaving the soil, it passes by the plant and can act as an amplifier of the infrared signal coming from the plant. Whereas the plant may have been initially broadcasting the signal, “I’m not balanced nutritionally,” the signal now reads, “Come and feed on me!”

Beetle eating a potato leaf
Unhealthy plants attract insects.

Dr. Reams taught that most insects do not attack healthy plants. His whole approach to plant fertility and insect control capitalized on supplying the soil balanced forms of plant food which, in turn, maximized plant health. Insects look for signals coming from unhealthy plants and seldom attack healthy ones. Insects willingly eat weeds and will return to that practice in fields with healthy crops and soils and unhealthy (low brix) weeds. The attacking of weeds by insects is one of the signs to look for in observing your progress toward sustainable agriculture.

Failing Plant Health

The research conducted by Dr. Callahan and Dr. Reams has immense implications. If insects attack unhealthy plants and ignore healthy plants, they are telling a sad story about the fertility approaches as currently practiced. By attacking unhealthy plants, insects are actually benefiting humanity by pointing out which plants are unhealthy, low in mineral content, and not fit for human or animal use. The astute farmer views insects, as he views weeds, as messengers of soil or crop conditions, not the cause of them.

Natural Control

Many farmers are beginning to work with the IPM (Integrated Pest Management) approach to insect control. President Clinton once announced his intention to have a large percentage of U.S.A. crops grown under IPM by the year 2000 in an effort to reduce the amount of toxic chemicals used.

This concept consists of setting out insect traps baited with the sex scent (pheromones) of insects and then observing insect populations. If the insects are present, but in a number below that which would cause significant crop damage, no spraying should occur. If the population indicates significant crop damage will occur, steps are taken to control their numbers, hopefully with non-toxic materials. Other aspects of IPM include the release of mating disruption pheromones or predator insects to devour the harmful ones present on the crop.

Increasingly, farmers are turning to non-synthetic pesticide options such as botanical, microbial or predator approaches. These consist of using plant extracts such as nicotine from tobacco leaves, pyrethrum from flowers, rotenone from roots as natural insecticides; using plant extracts such as garlic juice and capsicum from peppers as repellents; microbial vectors that destroy harmful microbes or larger organisms; and predatory insects to control insect pressures.

Ladybugs and lacewings are traditionally welcomed in the field as a predator of moths and other destructive insects. Additionally, their presence usually indicates a relatively low level of toxic contamination in the field, since they are also killed off by toxic sprays. Ladybugs usually are considered an indication that the field environment can sustain beneficial insect life.

Ladybugs act as a natural deterrent and predator to aphids.

It is important to consider using a foliar nutrient or feed with any type of insecticide whether synthetic or natural. Any plant under attack by insects is mobilizing its defenses. This requires nutrient and energy utilization. Wouldn’t it be wise to give some “chicken soup” to your crop along with anti-insect treatment to aid in its recovery?

An interesting natural product for insect control is diatomaceous earth. D.E., as it is commonly called, consists of the shells of tiny fresh or sea water diatoms which have been deposited on old lake beds over millions of years. They are mined and milled into powders for feed or for use as a filtering agent in swimming pools. The swimming pool product cannot be used in feed as it will damage the animal consuming it. Since it will absorb many times its weight in water, D.E. is considered to be an anti-caking ingredient for feed. It is often fed by alternative ag farmers, not because of its anti-caking properties, but because of claims it will control parasites in animals. Although it feels like talcum powder to the touch, you would see extremely sharp edges under a microscope. Supposedly, when the substance comes into contact with an insect it will scratch the insect’s cuticle. Death often follows from dehydration. How it works internally is not fully understood. Some think it de-energizes the parasite in the stomach.

Although only a few brands of D.E. on the market have gone through the EPA registration requirement to be considered a pesticide, other brands could work the same. Recent university research has shown that the vegetable oils used with pesticides may also give excellent insect control when used alone. However, the EPA has yet to “catch up” with this information and give its full “blessing.”

Could it be that insects and weeds are symptoms of a problem rather than problems themselves? Could it be that fertility approaches exist which can correct these basic problems exemplified by insect and weed pressures? Are these pressures related to fertility practices? If this is the case, how does the farmer determine the correct fertility program to use?

Up next: Chapter 6: Soil Testing

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About the Authors of The Non-Toxic Farming Handbook

Philip A. Wheeler has worked as the technical advisor and consulting agronomist for Crop Services International in Grand Rapids, Michigan. CSI is a soil testing lab and consulting service operat­ed by Phil and his wife Louisa. In addition to consulting work, he has worked for many years in the areas of research and development of agronomic products and technology. He received a B.S. in sci­ence education from Boston University, an M.A. in adult educa­tion from Michigan State University, and his Ph.D. in biophysics from Clayton University. He is a national lecturer on biological and sustainable agriculture and its relation to nutrition and health. An amateur dowser, graphologist and meta­physician, Phil also enjoys composting and gardening. He is a member of American Mensa.

Ronald B. Ward grew up in suburban Grand Rapids, Michigan. At the age of 9 his parents bought a 50-acre farm 25 miles away from their city home. They spent summers at the farm with Ron working for neighbors and gaining a love for both the coun­try and for the country life — milking cows, cutting hay and being a young farmer. He obtained a B.S. in park management from Michigan State University; a master’s of divinity from Asbury Theological Seminary; and a master’s in community counseling from the University of Kentucky. After working for and eventually directing the Lexington Central Kentucky Re-ED Program for emotionally disturbed children, Ron returned to his country roots where he was introduced to alternative health and the Reams method of testing urine and saliva. It was at that time that he, Phil Wheeler and Richard Vaughan founded TransNational AGronomy. Ron saw a need to provide growers with ready access to the firm’s lecture information and together with Phil authored The Non-Toxic Farming Handbook.