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The Agronomy of the future

Will not be based on chemistry but on biophysics and biology.

In the future, soil analysis will not be looking only at mineral balance and nutrient levels, but at the levels of amino acids, peptides, enzymes, carbohydrates, and other compounds that plant roots can absorb from the microbial community.

Agronomists will look at soil paramagnetism, redox, and electrical conductivity to evaluate a soil’s capacity to deliver to crop yields and quality.

Crop scouts will measure plant leaf redox and electrical activity to determine disease and insect susceptibility, and determine what treatments to apply to prevent possible infections.

The emerging knowledge of this space that is becoming more widely known is extremely exciting.

I posted a few weeks ago about Olivier Husson’s work on redox. His work is much broader and deeper than can be described in the referenced papers. He has been kind enough to appear on the podcast and to share his work in-depth in a six-hour-long webinar that we made available as a free online course on the academy that you can find here.

This will be the agronomy of the future. Enjoy.

 

2020-05-05T08:58:03-05:00February 12th, 2020|Tags: , , , , , |

The only thing that can not be overdone

Is balance. 

In regenerative and sustainable ecosystems anything can be applied to excess. 

Water can be excessive. So can oxygen. Or CO2. Or calcium, seaweed, biochar, humic acid, rock powder, liquid fish, crab shell, limestone, gypsum, manure, fertilizer, pesticides, and anything else you might name. 

You may have heard someone make a comment to the effect of “You can never apply too much of…(insert product here). 

You can be certain someone somewhere has done exactly that and suffered the consequences. Because there are always consequences of excesses. They are usually significantly worse and more difficult to deal with than deficiencies. 

2020-03-16T14:02:55-05:00February 11th, 2020|Tags: , , , |

Healthy plants can resist insects, including grasshoppers

Unhealthy plants transmit a variety of smells and EM signals that insects hone in on. Healthy plants don’t transmit these attractants, and they actively produce resistance compounds. Here are a few paragraphs from the podcast interview with Tom Dykstra:

Generally speaking, ethanol is a universal odorant that advertises itself as being unhealthy. So a lot of the plants will release not just ethanol, but also various alcohol components. Not all alcohols, but many alcohols advertise a plant as being unhealthy; it’s a hallmark of fermentation. Fermentation produces the alcohol.

And so when a plant is degrading and it’s in trouble and it’s fermenting, even in a small way—even in an imperceptible way—it will advertise itself. If these odorants are being released, they will be picked up by insects. It will change how the plants are perceived. You can take satellite images of two crop plants and they look different on various images. It can be a visible image. It can be an infrared image. They both may be corn. They both may be soybeans. They both may be anything you could think of, but they will not have the same look under an infrared camera or under a visible camera.

This is something which is very profound in grasshoppers. You don’t find them so much in the United States, but on other continents, locust swarms are a problem. These locust swarms are not just millions of individuals, but billions—sometimes trillions—of insects. They descend upon a very particular crop and take it all the way down to the roots and then pick up and fly away. And they will leave a farmer’s field right next to that exempt. These are the remarkable things that you realize when you see stuff like this— the grasshoppers made a decision. They made a decision to eat one plant over another. Why? Why didn’t they just come down and eat everything? We’ve always been told that grasshoppers will eat anything, and yet there is direct proof in some of the images that I have seen and testimonies of others that, no—they actually are very selective.

Now, I should tell you that grasshoppers are less selective than other insects. Some insects will disappear by a Brix of eight. Other insects will continue to chew on your plants right up through ten, eleven, or twelve Brix. But once they get to about twelve, they will lose interest. And the grasshoppers are among them. You can find the grasshoppers among slightly healthier plants for that reason, but you’re going to find that with the aphids, the leafhoppers, some of the other hemiptera insects, once the plant gets to eight, they lose interest in the plant. You just won’t find hemiptera insects on a plant above eight Brix. And those are the ones that have the beak that they stick into the phloem tissue and take a sip from the sugar water that is flowing around the phloem tissue.

So every insect has its own cutoff. You really have a lot of insects fall off by the time you get to eight. And as I mentioned at the beginning of this, most of the crops are between four and eight. So a lot of plants are really susceptible to every single insect that is out there. But if you can get above eight, you pretty much can take care of your aphids and your leafhoppers and psyllids. The Asian citrus psyllid is down here in Florida, and other psyllids, because it’s very rare to find a citrus tree that’s above eight. We’ve tested a lot of them.

2020-03-16T13:57:31-05:00January 22nd, 2020|Tags: , , |

How to Propagate Aphids

It is important to propagate aphids in our fields so the beneficial insects such as lady beetles have something to feed on. It is quite easy to produce a tremendous aphid population which can sustain a large number of beneficials and not be negatively impacted. We just need to give them the right environment.

Here are the easy steps to produce an optimal environment for aphids, which require free nitrates in the plant sap.

Step one, apply more nitrogen then the plants can utilize at the current growth stage.

Step two, do not supply magnesium for better photosynthesis.

Step three, do not apply sulfur the plants needs to produce sulfur-bearing amino acids and complete proteins.

Step four, do not supply molybdenum for the nitrate reductase enzyme.

Step five, do not apply any boron that might boost plant immunity.

If you follow these five very simple steps, you can be sure that your crop will provide the perfect food source for aphids. In addition, it will also be the optimal food source for many other larval insects such as corn rootworm, earworm, corn borer, cabbage looper, tomato hornworm, and others. Really for any larvae. Propagating these larvae provides a ready food source for songbirds and beneficial insects, a valuable ecosystem service.

Of course, if you do not desire to propagate these insects on your crops, the solution is obvious. Do the reverse of the five easy steps, and these insects will not be able to use your plants as a food source.

What defines a pest?

What is a pest?

When a wolf succeeds in catching a rabbit for dinner, which of them is a pest?

Is a wolf a pest while it catches rabbits and deer? When it catches a  lamb?

Is a rabbit a pest while it eats clover, or only when it eats the greens in the garden?

Is a ladybeetle a pest while it consumes aphids in the fields, or only when they swarm houses in the fall?

Is the definition of a ‘pest’ completely human-centric? It seems we call these living beings pests only when they bother us, but not when they bother other organisms we are not personally invested in.

We have deeply interdependent relationships with bacteria, fungi, viruses, nematodes, insects, amphibians, reptiles, mammals and birds of every kind. Almost all of these organisms are quite benign in healthy ecosystems. When the ecosystem is degraded, they proliferate, and begin feeding on the animals or plants we have a vested interest in. Then we proceed to label them as a pest or a pathogen.

But if it is us that has mismanaged the ecosystem, are we the pathogen?

The environment/ecosystem determines the presence and proliferation of all these living beings.

If we are to be stewards of these ecosystems, we must acknowledge that it is our management of the environment that determines whether these organisms express themselves as a benign participant or as a pest.

If we want to accept responsibility and make a difference, it does not seem useful to label living beings as pests.

Labeling is a subtle subconscious shifting of responsibility. “I am not responsible for these pests! They invaded! From out there. They are out of control. The weather was awful, the season was wet/dry/hot/cold.”

Neither the wolf nor the rabbit is a pest. They are symbionts in the environment and are dependent on the greater ecosystems they are a part of to sustain themselves.

Neither spider mites nor fusarium is a pest or a pathogen. Nor are any other insects, nematodes, bacteria or fungi. They are simply present in the environment we have created for them. If they proliferate to the point of causing crop loss, it is because we have managed the ecosystem to create an optimal environment for them.

If we desire them to not be present to the point of causing economic damage, we only need to manage the ecosystem differently.

2020-05-22T07:14:59-05:00December 12th, 2019|Tags: , , , |

Insect susceptibility determined by types of plant sugars

Sugar metabolism and carbohydrate synthesis are at the very foundation of plant health, but we generally don’t learn much about them in agronomy or even entomology. The types of sugars and the relative concentration of different sugars contained within the plant seem to be foundational in determining susceptibility/resistance to many herbivorous insects.

Here are a few excerpts from Harold Willis1 I found interesting:

The role of sugar in insect attack of plants is fascinating. Based on research done on various insect and plant species, apparently insects like moderate amounts of plant sugars and are attracted to plants containing them. But high concentrations of sugars are avoided by leafhoppers, grasshoppers, and the European corn borer2


Alfalfa was found to be resistant to pea aphid when its stem tissues had a more acid ph and higher levels of sugar (pentoses) and pectic substances (larger carbohydrate molecules formed by linked sugars). Pentose sugars are formed from hexose sugars which are the original products of photosynthesis. Alfalfa plants that are normally susceptible to aphids will become resistant if the above-mentioned cellular changes occur3

A possible reason that some insects avoid high sugar plants comes from research by G Fraenkel. Some sugars and sugar alcohol combinations (glucoside and mannoside) interfere with normal utilization of other sugars, and so are toxic to insects (mealworms)4. The inhibitory sugars are found mainly combined with other molecules in plants, but if digested by insects and in the presence of the sugar glucose, their toxic effects occur5.

Our knowledge of plant immunology has progressed well beyond this research in the ’40s and ’50s, but the practical application has fallen well short. I describe how we have applied these principles in our plant health pyramid infographic and on YouTube here.

1. Willis, H. Crop pests and fertilizers – is there a connection?

2. Thorsteinson, A. J. Host Selection in Phytophagous Insects. Annu. Rev. Entomol. 5, 193–218 (1960).

3. Emery, W. T. Temporary Immunity in Alfalfa Ordinarily Susceptible to Attack by the Pea Aphid. Journal of Agricultural Research 73, 33–43 (1946).

4. Fraenkel, G. Inhibitory effects of sugars on the growth of the mealworm, Tenebrio molitor L. J. Cell. Comp. Physiol. 45, 393–408 (1955).

5. Dethier, V. G. & Rhoades, M. V. Sugar preference-aversion functions for the blowfly. J. Exp. Zool. 126, 177–203 (1954).

2020-05-22T07:17:19-05:00December 7th, 2019|Tags: , , , |

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