Posts Tagged 'Biological Control'

Our Vision for Successful SPM: Part 8 Pest Management Myths and Truths

Ron Whitehurst, PCA and co-owner Rincon-Vitova Insectaries, Inc.

MYTH: “Chemical farming is based on sound science.”

TRUTH: The science that backs chemical fertilizer and pesticide use is largely “tobacco science”. It took 50 years from the time that tobacco was shown to cause cancer to get a label on a pack of cigarettes that said that smoking was linked to cancer. The tobacco industry paid scientists to do studies that “showed” that using tobacco did not cause health problems. Pesticide companies pay scientists to do studies that “show” that pesticides work and are needed.

Beware of the public-private partnership! Our tax dollars build public universities; but since we, as a society, support little pure research inquiring about biological control entomology, professors are forced to secure private money from pesticide companies to do research and trials on pesticides. Furthermore, peer review is not the sole measure of sound science. Unsound and biased study designs are often hard to detect. Peer reviewers can be, knowingly and unknowingly, compromised by not wanting to act against vested interests that could damage their careers. 

A common distortion resulting from study designs is the choice of the type of farming system used for trial plots. Chemical pesticides are trialed on farms where the plants attract pests that have been or are out of control. If the pesticide was trialed on farms with healthy plants where pests and beneficials were in balance, reduction in the pest density would not be statistically significant, and there would be no benefit over the untreated check, and no point in doing that study. It is easy to design a study to prove that a pesticide treatment killed significant numbers of pests compared to plots which received no treatment. This is beyond unsound–it is manipulated science. And yet there are peers who do not question this type of study design.

Peer reviewers can be, knowingly and unknowingly, compromised by not wanting to act against vested interests that could damage their careers. 

MYTH: “There is no evidence that healthy plants do not attract pests and disease.” 

TRUTH: There is an abundance of repeated observations that healthy plants are not subject to pests and diseases. Repeated observations are at least as valid scientifically as controlled variable peer-reviewed comparison studies. Those who make such repeated observations discuss them widely on webinars, but their observations will not be found in peer-reviewed journals and they are rarely invited to present at academic conferences. 

Scientists who want to study biological input-based agriculture, biological control and agroecology are excluded from funding and staff and can’t get their work published due to difficulty finding peers willing to review their papers. Everything they have done or want to do is effectively censored. They try to find funding from NGOs and unlikely sources. They may collaborate with a nearby hospital for the privilege of using their lab equipment. They may establish their own labs and sell services and possibly field trial contracts with pesticide companies and/or the EPA to support their own research. The funding pipeline from pesticide companies can even distort office relationships to the extent that those who refuse chemical pesticide and fertilizer funding are marginalized socially. Manipulated science is suspected in much chemical farming research while truth-seeking science regarding biological-input and biodiversity-based alternatives is suppressed. Sadly, the careers of those interested in honest research are negatively affected, or they are driven out of research institutions to be free to pursue such study and tell the truth. [Verhaaq, 2009]

MYTH: “Better living through chemistry; we can improve on how nature works.”

TRUTH: We live in a world of relationships. We are not disinterested, un-affected bystanders observing technology and marketing. Science tries to be objective as a means to a socially-accepted basis of truth. Adding toxins to our environment harms those beings with which we are in relationship: microbes that provide fertility in our soil, essential microbes in our gut, insects that pollinate our fruit, birds that eat pest caterpillars, lizards that eat ants, our children that fill us with joy, grandparents that share their wisdom.

“Technology” supporting nature is essential, but what most people understand as proprietary technology is not what it is cracked up to be. There are other ways of knowing and being in relationships. We must listen when those other ways contradict what “chemistry and technology” are saying. New federal policy requires that Indigenous Traditional Ecological Knowledge (ITEK) and internal methods of validating knowledge must be respected and plan programs that work with, not against, nature.

Adding toxins to our environment harms those beings with which we are in relationship…

MYTH: “A small amount of toxin in a large volume or area is diluted to have negligible negative effects, aka dilution is the solution to pollution.”

TRUTH: Fat soluble pesticides are biomagnified so that small amounts of toxin in an area can bio-accumulate. Insects feed on the toxin, and then it builds to toxic levels in the bodies of birds, bats and amphibians. Through the phenomenon of biomagnification, whale blubber and human breasts and prostate glands all become destinations for fat-soluble organochlorine pesticides in the food web. 

MYTH: “Ingenuity and innovation will yield new technological solutions to overcome problems of pesticide resistance, risks and residues.”

TRUTH: The only way to perpetuate funding for research is to manifest this myth that more study will yield a better patented product input solution. Because natural enemies and agroecological knowledge are not patentable, no vested interest has any incentive to spend money to fund such research. 

MYTH: “Farm Advisors help farmers consider alternatives to toxic inputs.”

TRUTH: The studies and trials paid for by pesticide companies become the basis for the recommendations included in the Guidelines by the UCIPM program and by the University of California Cooperative Extension. If a Farm Advisor wants to help a farmer consider alternatives, he or she must reach outside of what is found in University publications. There have been individual Farm Advisors over the decades who have made and disseminated their own useful observations about non-toxic alternatives, but that has not been the rule and some actively push toxic methods and marginalize biological methods at farmer meetings. For example, at a presentation about using Trichogramma to help control navel orangeworm, a UC Farm Advisor closed the meeting telling over 200 farmers that the pest would develop resistance to the Trichogramma wasps. 

The University of California and UC Cooperative Extension have long largely functioned as marketing arms of the pesticide and fertilizer industry with some wonderful exceptions. Test this yourself. Ask an Extension agent how to control a particular pest and observe. Chances are quite high that he/she will go to the UC-IPM Guideline and relay to you the chemical pesticides effective for that pest. Most agents need to be prompted to list the other IPM approaches for controlling the pest. 

Ask an Extension agent how to control a particular pest and observe. Chances are quite high that he/she will go to the UC-IPM Guideline and relay to you the chemical pesticides effective for that pest. 

MYTH: “Pesticides approved for use in California go through the most thorough, scientifically-based analysis and review in the world.”

TRUTH: Europe has much more strict hazard-based vs risk-based evaluation. Europe employs the precautionary principle. Evidence suggests and some Public Records Requests have revealed clearly that the US-EPA registration process is capable of and has perpetrated well-practiced blind acceptance of manipulated study designs and data (i.e. cutting off an animal toxicity study before tumors develop, selective inclusion of data, and/or excluding data showing harm by questioning the health of the control animals, etc.) to enable/legitimize pesticide manufacturers to pollute our shared public commons.

Additionally, because of their smaller size and accelerated metabolism, children are about 10 times more sensitive to pesticides than adults. But the intent of the registration process prioritizes getting toxic products on the market rather than protecting public health. Claiming that pesticides currently on the market are extensively tested is a false statement. 

MYTH: “Pesticide products are thoroughly tested for safety.”

TRUTH: Manufacturers submit required safety test data on the active ingredient in the product, but not on the adjuvants or on the formulated product as it is sold. The toxicity of the product on the shelf was not tested for the regulatory process. However, formulated pesticides are 10 to 100 times more toxic depending on the particular target organism. To accommodate this fact, toxic levels should be 1/100th of the published level. 

The current “safety” regime is not working. IF the intent is to prevent harm from proper use of pesticides, neighbors of farmers using toxic pesticides (according to label instructions) shouldn’t get sick, have a degraded experience of life, get cancer, and/or die. But the experience is that farmers that use toxic pesticides and their neighbors get sick. Globally, an estimated 44 percent of farmers, farmworkers, and pesticide applicators experience at least one incident of acute pesticide poisoning on the job every year, and 11,000 die annually from accidental pesticide poisoning. [Boedeker, 2020]

If the intent is to allow a certain percentage of citizens to get sick to enable pesticide companies to make a profit, that is neither acceptable nor ethical. Again, evidence shows that the registration process is merely a tangle of mental gymnastics designed to enable/legitimize pesticide manufacturers to pollute our shared public commons with impunity.

The toxicity of the product on the shelf was not tested for the regulatory process. However, formulated pesticides are 10 to 100 times more toxic depending on the particular target organism. 

MYTH: “These ingredients that are evaluated and registered by US-EPA go through over three hundred required human health and environmental safety studies.”

TRUTH: Let’s look at the case of Industrial Bio-Test Laboratories (IBT Labs) faking data for the toxicity of Roundup. The studies were never replicated, so Roundup has remained on the market for 45 years without valid toxicity studies [GMO Myths and Truths, 2014]. The much touted “science” is done by or for the pesticide registrant, muddied by a conflict of interest. This is science in service of the profit motive. If the study design is biased or lacking and stringent data handling procedures are not ensured, no amount of peer review of a fraudulent study can transform the results into sound science. 

Instead, the risk analysis amounts to an “acceptable” number of cancers or birth defects per 100,000 from using the product in a certain way. The individuals that put their bodies on the line with exposure to the pesticide, most often unknowingly because they trust that the government regulations protect them, do not have significant input into that decision. What is an “acceptable” number of cancers? In contrast to what? And to whom?

All the crops in CA can be grown organically without synthetic toxic pesticides, using natural pesticides which have zero risk of causing cancer. That is one of a number of reasons why the organic label must be utilized as the metric for setting transition goals away from toxic pesticides.

MYTH: “In a standard risk vs benefit analysis, any hazard from using a pesticide is mitigated (made OK) by restrictions on the label.”

TRUTH: A risk/benefit analysis assumes that there is a valued benefit to some entities from using the pesticide. Who benefits? The prevailing narrative is that the farmer benefits from using the pesticide to protect the crop; however, there are non-toxic alternatives for that pesticide. Additionally, using strong chemical pesticides disrupts biological control on organic and regenerative farms where pests are managed using cultural or mechanical methods and (soft) bio-pesticides where necessary.  Introducing a toxin therefore provides no benefit to the people involved, whether they be farmers, farm workers, or the neighbors living and working nearby. There are likewise negative impacts from introducing a toxin into their surrounding environment. 

There are financial benefits for the pesticide manufacturer, distributor, and salesperson from selling the pesticide, which are often justified as beneficial to the economy. So the farm worker is required to risk cancer for the benefit of the “economy”, meaning the pesticide industry sector. Is this a trade off that you would accept?

MYTH: “Despite the US-EPA registration process, products entering California undergo an independent second comprehensive evaluation by DPR scientists before being registered for use. DPR also requires additional “California only” studies before registration reviews are complete. This process is very painstaking and slow (taking 5-7 years) because DPR wants to be sure the new product has some level of efficacy and can be safely brought to market in California.”

TRUTH: Based on what has been reported by retired EPA scientists and discovered in Public Record requests, most of the studies submitted to the US-EPA for review could be flawed. There is enough evidence to conclude that none can be trusted without a fresh review looking for flaws, biases, and/or high-level US-EPA administrative intercession on behalf of pesticide manufacturers overruling the recommendations of rank and file scientists. The same studies are sent from the US EPA to the CA EPA. The conflict of interest resulting in flaws and biases in required toxicity studies moves unchanged from the federal to the state regulators. 

The slowness of CA EPA to review such new products is apparently not because of the extra care taken in the review. There is at least an appearance that the review process is being overseen by individuals who are influenced by powerful pesticide companies. In a typical “good ol’ boy ” culture, decisions are based on the belief that pesticides are necessary “tools” to grow our food. Meanwhile DPR accepts the risks associated with registering new pesticides, and farms continue to be sacrifice zones, and farmworkers disposable pawns in the registration game. 

CA EPA could streamline the process for review of new and biorational pesticides, but assessments need to be based on hazard and not risk. 

The conflict of interest resulting in flaws and biases in required toxicity studies moves unchanged from the federal to the state regulators. 

MYTH: “Additional label restrictions on products protect public safety, like Restricted Use Pesticides (RUP), and Agricultural Commissioners have discretion to require even more restrictions when conditions in their counties may require them. In addition, Agricultural Commissions must be given a Notice of Intent (NOI) prior to an application of a RUP based on risk parameters established through the product’s registered label and DPR’s registration requirements.”

TRUTH: No amount of pseudo religious legal ceremony or certified papers will change the fact that using toxic pesticides is an aggressive act. The non-aggression principle is a good approach to interacting with others. Putting a toxin into the commons (my space) that has the potential to make one sick, poison livestock, poison wildlife (food for some), and pollute resources is an aggressive act. This is done without the consent of those affected. 

MYTH: “Pesticides are safe when used according to label directions.”

TRUTH: We hear continuing reports from farmworkers who are sickened by exposure to pesticides in the fields where they work. Farmworkers who are sickened by exposure to pesticides in the fields have many reasons for hesitating to ask questions or express a grievance. Scientific reports show low sperm counts, birth defects, fertility problems, from neonics (endocrine disruptors) which are considered low risk pesticides. There are also reports that safety training is superficial and does not adequately explain the risks if someone does not follow the label instructions. There is no information on the label about cumulative risks and synergistic effects and whether the formulation is more risky than the active ingredient.

Public health professionals around the world talk about One Health, the combination of ecological, human, social health, and others talk a bit more broadly about Planetary Health.[Garnier, et. al. 2020]

“Farmworkers who are sickened by exposure to pesticides in the fields have many reasons for hesitating to ask questions or express a grievance.”

MYTH: “American farmers need to feed the world.”

TRUTH: It is true that the climate crisis, supply line disruption, and political unrest point to food shortages and famine. Someone in the world is dying of hunger every four seconds. As a parent I empathize with parents watching a child die for lack of food. But the solution is not shiploads of devitalized GMO corn and dairy milk powders from cows living on GMO feed. Solution: pay for the loss and damage to countries suffering climate impacts who did nothing to cause it, ensuring that it goes into capacity-building for small-holder agroecosystem restoration.

Industrial agriculture to feed 30% of the world’s population is using 80% of the world’s land, water, and fertilizer. Smallholder farmers with less than five hectares of land feed 70% of the world with resources that they regenerate. 

There are effective ways to help these small farmers be successful, such as appropriate trade agreements and political alignments so that farmers in poor nations can compete with internal and external corporate agriculture interests, make land-grabbing and water-grabbing by US-based entities illegal, and invest in restoration of land and small water cycles for resilience to climate impacts. America needs to overhaul every US AID program from food aid that destroys markets for local farmers to Farmer to Farmer that arrogantly exports myths about industrial agriculture efficiency. The world would benefit if American farmers focused on their own soil conservation and crop diversification, including increased perennial cropping and cover cropping for climate and economic resilience. They could even consider welcoming immigrants seeking asylum as neighbors and co-learners in rural resilience strategies.

“U.S. farm exports do not go to the nations that suffer the most from hunger but to nations whose consumers can afford to pay global market prices. An analysis of U.S. farm exports for 2015 found that 86% of U.S. farm exports went to 20 nations classified by the United Nations as medium-to- highly developed, and only half of one percent went to 19 of the least developed nations, including Haiti, Yemen, and Ethiopia.” (Environmental Working Group, 2016).

MYTH: “It will take a long time to turn around a chemical input-based farm.”

Truth: Soil Food Web trained consultants and regenerative agriculture consultants have successfully reversed degraded fields in one season with experienced help. The knowledge and experience in soil and sap analysis works to dramatically reduce fertilizer and pesticide use and tillage. The duration depends on soil type, compaction, weather or climate, and the level of soil degradation.

John Kempf of Advancing Eco Agriculture uses primarily sap analysis to plan foliar nutrient sprays and soil inoculants to ensure healthy plants and a healthy plant microbiome to produce a good crop. Soil Food Web technicians ensure high quality compost is used for side dressing, teas and extracts, determine what functional groups of bacteria, fungi, protozoa and nematodes are missing, and suggest appropriate practices and inputs to build life in the soil. 

It often used to take three to five years to repair degraded soil and it still can in some soils, but with skilled, experienced help it now takes less time. It is an existential imperative to start now. We need to sequester carbon in soil and we can reduce pesticide use when plants are healthy and don’t have pests. 

When we get it right we can transform a desolate, degraded landscape into a lush, productive, veritable paradise in a couple years. What do you want for your legacy?

“It is an existential imperative to start now because of the potential for biological carbon sequestration.”

MYTH: PCAs are well trained and licensed to protect the public health.

TRUTH: The words of Robert van den Bosch in 1978 could have been written today:

“The examination and licensing law has been a severe setback to the development of a rational pest-control system in California, because it drapes the pesticide salesman with a mantle of professional respectability and thereby enhances the myth that he offers competent and objective advice on pest-control problems. Now when the salesman flashes his business card to a prospective customer, it bears the impressive title licensed pest control adviser, and this title is backed by a document bearing the seal of the great state of California. The salesmen are so proud of their newly achieved respectability that they have formed an organization, the Council of California Agricultural Pest Control Advisers, to advertise their transition from peddlers to “professionals.” But despite their instant professionalization, they remain salesmen, and rational pest control suffers because of their legally sanctioned camouflage. California’s Agricultural Pest Control Advisory Committee, with its inclusion of chemical company employees and a pest-control operator (spray applicator), fortifies the misconception that pest control and chemical control are essentially synonymous….Thanks to the politics of pest control, the pest-management advisory profession seems destined to decades of mediocrity, and the environment to a continuing biocidal blight.” Van den Bosch (p.96-7) 

“Integrated control is simply rational pest control: the fitting together of information, decision-making criteria, methods, and materials with naturally occurring pest mortality into effective and redeeming pest-management systems.” Van den Bosch (p.151) 

Thanks to the politics of pest control, the pest-management advisory profession seems destined to decades of mediocrity, and the environment to a continuing biocidal blight.” Van den Bosch (p.96-7) 

MYTH: Access to a suite of effective and feasible ‘alternatives’ to high-risk pesticides” is what is most needed to reduce economic risk.

TRUTH: This is the “efficiency/substitution” attempt to stay within a chemical input-based farming system. In chemical farming systems “alternatives” generally refer to chemical pesticides.  However, every crop can be grown in a biodiversity-based farming system that best mitigates every risk. For resiliency we need to move to biodiversity-based or regenerative farming systems. The reduction of risk is primarily in whether the farmer is open to increasing biodiversification. Reliance on cheap pesticides is a major economic risk growers bring on themselves. Greater profitability is achieved when healthy soils yield healthy plants that need few inputs.

MYTH: PCA certification is working, we don’t need to fix it.

TRUTH: Martin Guerena, Sustainable AGriculture Program Specialist, with private non-profit National Center for Appropriate Technology–ATTRA, made these observations about the challenges for Pest Control Advisors: 

Especially with annual vegetable and strawberry growers, Martin Guerena observes that a lot of them would spray regardless of a need.”It was like insurance. And a lot of times it was not needed, yet they sleep better knowing the product has been sprayed, especially about two weeks before harvest, maybe even a week before harvest, just so when they get to harvest there won’t be an issue. It’s twisted. But that’s how it is. And I’m sure just those two factors alone would reduce useless use of pesticides tremendously.”

“The structural issue of PCA sales incentives must be fixed. Incentives to sell chemicals trump good sense.  Scouting needs to become a serious trained occupation, paid for unbiased, high quality information.  Chemical sales consultants should stop masquerading as knowledgeable agronomists.  Making this happen seems both essential and very difficult….The fact that PCAs working for chemical companies work on commission, so the more they sell, they are stimulated or incentivized to sell more chemicals than are actually needed. That is a big political issue.” 

No matter how much training and additional certifications are added, unless the conflict of interest occurring when people receive commissions on pesticide sales is addressed, this critical role in pest management advising for farmers will bias farming toward synthetic pesticide use. Pay PCAs a good flat rate with no commission, and then have them recommend whatever they need to recommend. But with a commission on how many pesticides they sell, of course, the more they sell the more money they are going to make.   

California Code for Pest Control Advisor Regulations must be amended to require (a) Each licensed agricultural pest control adviser and grower, when determining if and when to use a pesticide that requires a permit, shall write up a biological and/or organic treatment methodology for consideration, which would substantially lessen any significant adverse impact on the environment.

Amend Code 6556 to read:  Each recommendation shall include: (e) Certification that written methodology of biological and/or organic treatment measures that would substantially lessen any significant adverse impact on the environment have been shared with the grower (or written by the grower who is also a PCA).  The code must delete “if feasible” because every crop in California can be grown organically.

A standing advisory committee is needed to guide the development and continual improvement of SPM educational curricula, composed primarily of entomology and agroecology instructors at state and community colleges.

Pay PCAs a good flat rate with no commission, and then have them recommend whatever they need to recommend.

MYTH: Transforming agriculture to regenerative will not reverse climate change. The models forecast uncertain capacity to sequester carbon.

TRUTH: This negative prognosis is the result of reductionist framing, that the whole is the sum of the parts. It is ignorant of the emergent properties of complex systems that are more than the sum of their parts. 

We are looking at horribly degraded landscapes. When people colonized California they killed the beavers, cut the trees, overgrazed with cattle, plowed, fertilized and poisoned with pesticides that reduce the capacity of living soil to sequester carbon. Glyphosate herbicides are ubiquitous even in government programs for soil conservation. Never mind that they chelate minerals so they are unavailable to the plants, compromising plant health, reducing their defenses against pests. The landscape we now see will not pull carbon dioxide from the air in any great quantities. We can realize a better future, by transforming our agriculture to intensive horticulture, creating food forests, providing meaningful work, food, clothing, supply medicine, restore small water cycles, buffer weather extremes, and move our economy of scarcity to one of abundance. With directed work we can recreate a paradise on Earth.[Kravcik, 2012]

Cautious estimates of carbon sequestration look at increasing organic matter in the top six inches of soil, the plow share. With perennial agriculture, we can look at increasing organic matter in the top 2 meters of soil, with no practical limit on how much carbon it can hold. Of course we are not looking at a static situation, we are talking about increasing the cycling of carbon, through a living system.

Our landscape has been de-watered. We are causing warming and drought by the way we manage the land. If we increase the latent heat of evaporation by covering the soil and moving to perennial crops, rain will sink into the ground and be available to grow trees which cool the earth, recreating small water cycles.This is the same process as when you get out of the pool and the wind blows and you feel cold as the water evaporates from your skin. When we plant a 100 km2 area (about 40 square miles) with trees, we change the weather. 

The California Air Resources Board unfortunately appears to believe that the available models are all they have on which to base incentivizes for carbon farming. We suggest that time is wasting given that there are people who have the necessary knowledge and experience to speed up the transition to biodiversity-based farming systems characterized by deep roots, high microbial and carbon levels, and reduced pests and pesticides. We need to charge in with ambitious goals within a plan of adaptive management and on-going evaluation.


Boedeker, W., Watts, M., Clausing, P. et al. The global distribution of acute unintentional pesticide poisoning: estimations based on a systematic review. BMC Public Health 20, 1875 (2020).

California Code of Regulations (Title 3. Food and Agriculture) Division 6. Pesticides and Pest Control Operations, Chapter 2. Pesticides, Subchapter 4. Restricted Materials,  Article 3. Permit System

Fagan, J., Antoniou, M., Robinson, C. GMO Myths and Truths–An evidence-based examination of the claims made for the safety and efficacy of genetically modified crops and foods. 2014, EarthOpenSource, 2nd Ed.

Garnier, J., Savic, S., Boriani, E. et al. Helping to heal nature and ourselves through human-rights-based and gender-responsive One Health. One Health Outlook 2, 22 (2020).

Kravcik, M. Water for the Recovery of the Climate – A New Water Paradigm, 2012.

Van den Bosch, R. The Pesticide Conspiracy, 1978. Reprint University of California Press.

Verhaag, Bertram and Verena Schonauer (Directors), Arpad Pusztai, Ignacio Chapela, Scientists Under Attack: Genetic Engineering in the Magnetic Field of Money, 2009 Documentary film 88 min.


Our Vision for Successful SPM – Part 7: What has to be different for SPM? [Hint: Life]

Ron Whitehurst, PCA and owner Rincon-Vitova Insectaries, Inc.

“Working with these species in a bio-diverse agroecosystem will require specific training and the ability to evaluate the pest-crop-beneficial input dynamic in very diverse locations. Biological control is a cornerstone of IPM.” – Entomologist Lynn LeBeck, Executive Director, Association of Natural Biocontrol Producers 

In biodiversity-based farming systems, also referred to as regenerative organic, farmers reduce inputs and increase profit through building soil and plant health and increasing biodiversity. Sustainable Pest Management (SPM) recognizes that successfully transitioned regenerative organic farms have few pest problems and little or no pesticide use. This is because natural control is achieved by the presence of a pests’ natural enemies maintaining a proportionately high ratio. To support the transition to regenerative organic farming, monitoring and interventions related to biological control is a major field for Research and Extension investment along with development of new effective biopesticides for the Roadmap to achieve its goals. For six decades the centrality of biological control has been understood by leaders of thought about pest management.

In this article we survey contributions to the history of Integrated Pest Management (IPM) to understand why it has not prevented pest infestations, nor reduced the number of new pesticides or the level of their use, and explore what needs to be different when using Sustainable Pest Management (SPM).


My mentor, Deke, met Prof Harry Smith and his cadre of biocontrol entomologists when he want to graduate school at UC Berkeley on the GI bill after serving in the Coast Guard in the Pacific Theater. He appreciates Richard Doutt for directing him to the biocontrol team. Deke left Berkeley for a job at the University of California Citrus Research Station and after 12 years doing field research in many crops, he left the university because there was no more funding to do biological control research. He wrote, 

“UC Farm Advisors and county agents in addition to the UC researchers in the Department of Entomology were particularly supportive of pesticides.  Only a very few would carry on a dialog about integrated control and least of all IPM.  Their mantra was to apply pesticides whenever what was left of the natural biological control failed and of course it failed when broad spectrum chemicals were applied.  Integrated control was monitoring and spraying every time the economic threshold was reached.” [Unpublished memoirs]

He built a business mass-producing beneficial insects and selling a service to farmers that he called “Supervised Control”. Deke’s insights and enthusiasm convinced farmers in the Imperial and Coachella Valleys to stop calendar DDT spraying of cotton by selling egg parasitoid wasps (Trichogramma) for cotton bollworm.  Having learned during twelve years with the University of California Department of Biological Control surveying insect ecology on “untreated” farms  in the years prior to “organic”,  his business expanded with a dozen Supervised Control consultants using applied biological control instead of pesticides, successfully persuading farmers of the method’s effectiveness.  

During such conversations with farmers, he often listened for the moment when a farmer was visualizing the interaction of the problem pest and the “natural enemy complex” on his or her farm, as the farmer would eventually ask a question about how the insect ecology worked if you introduced natural enemies. Deke would say, “Food drives all these systems.” As that understanding sank in, the farmer stopped being fearful and began to show curiosity about how to observe insect ecology. Once he or she recognized that both monitoring information and consideration of alternative actions focused on conserving natural enemies, the farmer rarely ever resorted to chemical pesticides again. These are the same principles, features, and pedagogy that direct our company Rincon-Vitova Insectaries today.


In a 50th anniversary commemoration of what is considered the “most important” pest control paper of the 20th century, a 2009 article in California Agriculture recognizes the scientists behind the framework that became Integrated Pest Management. The 20-page paper explains the damage from pesticides and proposes the consideration of multiple methods that would be more effective and better protect farmworkers and the environment. The commemorative article summarizes IPM principles without giving full credit to their development in the work of field researchers like Everett Dietrick who developed the applied insect ecology strategies first called “Supervised Control”:

  • Recognition that agriculture is part of a larger ecosystem, comprised of all the living organisms of an area and their environment.
  • Supervision of insect levels so that chemical applications take place only when and where they are absolutely necessary.
  • Promotion of beneficial insects through conservation and augmentation.
  • Use of products and application timing to target specific pests, minimizing the effect of treatment on pests’ natural enemies.

Authors of the visionary article, Vernon M. Stern, Ray F. Smith, Robert van den Bosch and Kenneth S. Hagen, are now called ‘the fathers of IPM’. However, Deke would say that the concepts came out of the preceding decade of development of Supervised Control by the larger team of field researchers and consultants. Vern Stern’s primary contribution was that he recognized the collective visionary insights of those around him and led in writing them down.


Deke recalled passing the exam in all categories in 1974. He wrote, 

“There was nothing written or questions asked about the ecological basis of pest management and natural biological control. It seems that IPM is all about chemicals and mortality from these powerful pesticides and not about beneficial insects and the interference of the pesticide applications to the work of these biological control organisms. Applied biological control organisms were not covered, nor was there anything suggesting that natural enemies are destroyed in a blowback and resurgence of pests following a pesticide application.” [Unpublished memoirs]


Clara Nichols and Miguel Altieri in their book chapter entitled “Agroecology: contributions towards a renewed ecological foundation for pest management”, explain the theoretical principles about transition in a farming system framework. They state that the desirable attributes of stability and resource conservation “are connected to the higher levels of functional biodiversity associated with complex farming systems.”  It is clear, they say (referring to Southwood and Way, 1970) that insect population stability depends on “the actual density-dependence nature of the trophic levels”, not just on trophic diversity, specifically on who eats who.

In other words, stability will depend on the precision of the response of any particular trophic link to an increase in the population at a lower level.” 

They also had this to say about biodiversity-based farming systems: 

“Diverse systems encourage complex food webs which entail more potential connections and interactions among members, and many alternative paths of energy and material flow through it. For this and other reasons a more complex community exhibits more stable production and less fluctuations in the numbers of undesirable organisms.”

1994 INTEGRATED PEST MANAGEMENT: THE PATH OF A PARADIGM by James R. Cate and Maureen Kuwano Hinkle. Excerpts from recommendations, pages 30-33:

  • The first need is…a clearly articulated definition of IPM that goes beyond use of monitoring and economic thresholds restoring the ecological basis of IPM.
  • Regulatory incentives can encourage the development and registration of biological alternative products.
  • Pest management should be directed at developing solutions that provide durable, long-term controls [by] a systematic assessment of key pests and the nature of the ecological upset or imbalance that has caused a pest problem.
  • Funding of programs needs to be maintained over a decade or more and implementation projects often require three to six-year commitments. 
  • Funding needs to be allocated in a way that avoids agency competition, turf disputes, and conflicting purposes [in a] competitive grants program of basic research, mission-oriented research, and implementation grants…
  • Adoption by farmers…is best accomplished by having the users be active participants in the development and implementation teams….A team building structure would help to diffuse technological advances quickly and establish a social and cultural receptivity to continued practice and improvement of IPM…
  • The advice should not be influenced by the commercial need to generate sales of specific products. 
  • Inducements could be in the form of crop risk insurance for users and private crop consultants and in the form of IPM program development incentives to users, particularly during the transitional periods when growers are moving to ecologically based management from chemically based management.
  • Inducements could also be in the form of predictive models and information that can be used by consultants and users to forecast pest population models and seasonal growth of crops, pest populations, and populations of biological control agents. 
  • Pest management cooperatives could be encouraged with incentives to assist farmers and neighbors in addressing pest problems in area-wide and systematic ways.
  • Building on the scientific principles that support an ecologically based IPM, and the original concepts of Integrated Control, IPM is a useful organizing principle around which utilization of all technologies can be integrated—biological controls, host resistance to pests, biotechnology, alteration of the cropping system, etc.— to facilitate natural controls or antagonists of the pest or to create a more unfavorable environment for the pest. By focusing on the basic causes… and appropriately addressing different types of pests, we can manage pest populations so they no longer damage crops, goods and human health.

1996 NAS: EBPM

National Academy of Science report (1996), Ecologically Based Pest Management (EBPM) stated that EBPM “should be based on a broad knowledge of the agro-ecosystem and will seek to manage rather than eliminate pests” in ways that are “profitable, safe, and durable.” Its vision was the transition of agriculture to a total-system approach in an agroecological framework.


National Academy of Science (1997) Proceedings paper, “A Total System Approach to Sustainable Pest Management,” went further in calling for “a fundamental shift to a total-system approach for crop protection [which] is urgently needed to resolve escalatory economic and environmental consequences of combating agricultural pests.”  Successful transition to SPM operates in the context of the type of farming system in which one is working. In the context of a new Roadmap for Sustainable Pest Management, we need to be unambiguous about which “system” we are referring to.


As plants developed inherent protective mechanisms against pests, they were assisted by numerous partners in the ecosystem, including:

A total-system approach was then well described in Sustainable Agriculture Research and Education (SARE) Handbook 7, Manage Insects on Your Farm – A Guide to Ecological Strategies (2005) by Miguel A. Altieri and Clara I. Nicholls with Marlene A. Fritz. They wrote that EBPM (EPM for short)

employs tactics that have existed in natural ecosystems for thousands of years. Since the beginning of agriculture— indeed, long before then — plants co-evolved with pests and with the natural enemies of those pests. 

  • Beneficial insects that attack crop-eating insects and mites by chewing them up or sucking out their juices
  • Beneficial parasites, which commandeer pests for habitat or food
  • Disease-causing organisms, including fungi, bacteria, viruses, protozoa and nematodes, that fatally sicken insects or keep them from feeding or reproducing. These types of organisms also attack weeds.
  • Insects such as ground beetles that consume weed seeds
  • Beneficial fungi and bacteria that inhabit root surfaces, blocking attack by disease organisms” [page 2]  


As he explains in this paper, David Headrick, Professor of IPM and Biological Control at Cal Poly SLO, trains PCAs and sees them as a critical link in the transfer of knowledge and skills to the growers for site-specific problem-solving, toward a goal of diverse cropping systems. He also explains that the California State Universities (CSUs) are the primary educational institutions training future PCAs.  So, the CSUs must be included in the discussion regarding implementation. 

Dr. Headrick sees a continuum from chemical-reliant systems to biological-dependent systems, but he supports the framework we have adopted of a continuum of three basic types of farming systems: chemical input-based, biological input-based and biodiversity-based.

Dr. David Headrick in “Scouting for pests – Virtual Avocado Field Day at Cal Poly” 

There may currently be more progress in other parts of the world where public investments are addressing the climate crisis. INRA, the French National Institute for Agricultural Research, began publishing papers in 2015 about a framework for study of farms in transition. Beginning in 2020, it merged with IRSTEA, the French National Research Institute of Science and Technology for the Environment and Agriculture to form INRAE, the French National Research Institute for Agriculture, Food and Environment, creating a critical research mass and pooling of labs and observatories, technical platforms, data repositories, etc. making it uniquely able to perform valuable research on the preservation and restoration of biodiversity and risk anticipation and management, as well as regional agricultural strategies, water resources, digital agriculture, and more. 

The INRA, now INRAE, framework for characterizing farming systems informs the following discussion:


Deke called these systems Conventional Chemical Control (CCC) to distinguish them from Biological Control by Natural Enemies (BC by NE) systems. He often described very different interventions in such systems belonging to neighbors or family members growing the same crops. “Both are right”, he said, “because what works in a BC by NE system won’t work in a CCC system.” 

At one end of the spectrum are chemical input-based systems under eradication programs for invasive species. Since the pest is usually eventually declared established and the state can no longer conduct area-wide eradication, as Dr. David Headrick explains to his Plant Protection students, “Then it’s biological control to the rescue for a long-term solution to avoid economic losses and having to use insecticides.” This leads to a discussion of the problem of pesticide resistance and how to manage that by alternating pesticides with different modes of action. Since their inception, bio-control entomologists have advocated against total eradication programs, because they practically never succeed and the spraying is highly disruptive. 

Another characteristic of chemical input-based farming systems is the degree to which they are embedded in globalized commodity-based food systems that favor large growers and distributors far removed from consumers and end-users. This allows producers to be invisible and thus less accountable for negative health and ecosystem impacts. The Roadmap toward SPM is timely because opposition to the resulting pollution and lack of accountability is steadily growing. 


Distinguishing between biological input-based and biodiversity-based farming systems in the pest management transition continuum is increasingly important. Differences lie not only in the relationship between biodiversity and biological control of pests described above.  We now have insights that increasing biodiversity is correlated with accelerated timelines and community tipping points when sufficient multiple species are growing together. Beneficial increases in measures of soil health, carbon sequestration, plant fertility, pest resistance, water penetration and water-holding capacity, and resilience to climate impacts all result.  Past understandings of risk to benefit ratios and economics are shifting toward a wider scope of valuable characteristics not always found on typical organic farms that are biological input-based systems. 

Biological input-based systems (most organic acreage in California) are still usually relatively simple systems and not evolved to provide much in the way of the above-described biodiversity benefits compared to what is experienced in regenerative farming systems that build on the best practices for soil aeration, hydration, protection and fertility with well-developed and conserved soil microbial biodiversity and habitat enhancements for natural enemies.  Biological input-based farming systems are a middle area of the continuum between chemical inputs and biodiversity-based systems that have more complexity and more resilience with fewer inputs.

The “efficiency/substitution” paradigm analyzed by INRAE scientists, especially when it prioritizes “alternatives” without the end-goal of biodiversity, limits the language and patterns of thinking in contrast to a more biodiversity-based paradigm for transition. Successful consultants in regenerative agriculture within our network quickly recognize the limiting belief that soft chemical or biopesticides are essential for SPM.  Experts holding the paradigm of “efficiency/substitution” are understandably averse to setting goals for transition to organic, because from a farming system perspective it is far from perfect with some strict prohibitions that are not pragmatic. 

However, there is no doubt that the organic label from a policy and economic perspective will drive adoption of SPM. The federal government is investing in transition to organic and the state must do so as well by removing all fees and inspection costs, by providing a full day of expert consultation toward an Organic Farm Plan, and by requiring the public kitchens purpose increasing percentages of local organic products. Organic farming systems are not the objective, but rather a stepping-stone on the path to regenerative biodiversity-based farming systems. The marketing value of the organic label cannot be squandered. It is the ideal metric for incentivizing accelerated soil carbon sequestration and advancing SPM. Buyers can be educated and also in some cases required by their institutions to seek out those inquisitive, determined, pioneering organic farmers that have at least begun to care for the soil and wildlife, have stopped toxic chemical inputs, and are on the path to profitable biodiversity-based farming systems. 

Hence, the SPM Roadmap must feature the recognized co-benefits of biodiversity PLUS the following: 

  1. Biodiversity-based systems offer long-term success that is unlikely when “alternatives” and substitution of soft chemical and biopesticides are disproportionately spotlighted in the middle part of the farming system continuum. 
  2. The organic label is the most powerful metric to drive consumer investment and rapidly scale transition regardless of the scientific rationale of the standards or the net value to farmers of inputs and practices. If there are anomalies or absurdities in the Organic Standard, they can be fixed while focusing investment in transition to organic. 
  3. Regenerative organic agriculture is trending and is powerful in featuring incentives beyond the basic organic label, because of its focus on soil carbon and potential carbon or eco-credits, not to mention it providing the greatest economic and ecological resilience or the farmer. 


We don’t want alternatives. We want to do what is actually most effective for the long term. The limiting paradigm of “efficiency/substitution”-based agriculture and the limits of a “sustainable agriculture” framework are discussed in two papers from the preeminent research team at INRA [Duru 2015; Therond, 2017]. In the Duru paper the limiting aspect of the “efficiency/substitution paradigm” relative to the “biodiversity paradigm” is discussed. Framing transition in an “alternative or substitution mindset” will increasingly limit capacity to do what is most effective in the long-term. “Substitution thinking”, in fact, has already led to unfarmable land because of climate impacts. That is just the beginning of the difficulties that lie ahead.

“Efficiency/substitution” farming systems are often held up as “Best Management Practices” in a hierarchy of recommendations in UC-IPM publications with conventional chemical control presented FIRST and biological control presented as a chemical substitution or alternative. As such, the University of California imposes a top-down hierarchy of upside-down guidelines resulting from partnering with the companies selling patented products for profit.  The aim of these companies, and the researchers funded by them, is increasing efficiency and reducing costs and pollution by comparing a lower-risk alternative with a chemical control in a chemical input-dependent farming system test plot. Where is the biodiversity-based control?

At the meetings where Pest Control Advisor’s pay to receive Continuing Education Units, they generally hear product representatives and Farm Advisors sharing new information about which product killed more pests and what additional crops a pesticide produce label now covers. There is nothing on a chemical label about approved use of a product on a farm in transition away from being chemical input-based, such as potentially spot spraying based on a modified action level. Experts teach that their findings are uniformly applicable across all farms. By contrast, what if there were CEUs given for PCAs to learn how to recognize or build a biodiverse, problem-free system anticipating no need for alternatives to chemical pesticides?

I made a proposal recently to talk about biological control and cover crops that was rejected by DPR for CEUs. Our General Manager with nearly two decades of experience helping customers manage pests biologically was required to take twelve hours of courses in production farming and IPM centered around pesticide laws and regulations. She can now take the PCA exam and little to no questions will reveal the depth of her knowledge about SPM. The current dominance of the “efficiency/substitution” paradigm needs to change.  The pendulum seems to swing back and forth regarding acceptance of CEU’s for ecological approaches.

Farmers who demand urgent availability of “alternative” products before agreeing to consider changes in their practices are seriously hurting themselves. Climate impacts and particularly water shortages will teach them that they should have prioritized transition and said goodbye to pest management tools that hold them back.  The Roadmap should nowhere even faintly suggest that “alternative” inputs are the end-goal for SPM when we know that durable transition is attainable by increasing above- and below-ground biodiversity with its co-benefits, including low incidence of pest problems. 

In the words of Dr. Annemiek Schilder, Director of the Ventura County University of California Cooperative Extension office, 

“In the end, it is all about increasing biodiversity across the system, from the soil and roots to above-ground plant parts to the landscape and region, to increase efficacy and resiliency/robustness of the agroecosystem. There is a lot we don’t know, especially how soil health affects plant health….Within this, there needs to be a focus on understanding ecological principles, interactions and population dynamics of beneficial and pest species, as well as the role of and how to measure farm biodiversity. Also, is all biodiversity good or do we need specific components for a pest/disease-suppressive system?”

Dr. David Headrick, Entomology Professor at Cal Poly San Luis Obispo also encourages research that helps discriminate about how to diversify the cropping pattern: 

“In thinking about the tactic of diversifying the farmscape, I hope that the SPM workgroup can appreciate and acknowledge that diversification of an agroecosystem occurs on a spectrum.  On one end of the spectrum you can have the addition of a single plant to a monocrop; on the other end of the spectrum you can have hedgerows and insectary plantings in a polyculture farmscape.  It would be wrong not to acknowledge the efforts of current growers in Salinas in diversification.  Twenty years ago, the standard method for aphid control in row crops was an early application of Metasystox-R, an extremely dangerous systemic organo-phosphate.  But now many of them plant sweet alyssum to attract syrphid fly predators and get excellent control of aphids. This is thanks to the work of Eric Brennen with the USDA-ARS at his organic research farm in Salinas, and others.  By adding one additional plant – increasing the diversity of the cropping system – they have an excellent tool that invokes the natural aphid control provided by naturally occurring syrphid flies.”  

“So, on one end of the spectrum, we can have a single plant increasing the diversity of a monocrop that eliminates the need for one of the worst insecticides.  To me that is remarkable, worthy of note and is a significant step on the Roadmap toward Sustainable Pest Management and should be acknowledged as such.  This example also shows the successful collaboration of the research and grower communities.  At first, the alyssum was planted in several rows throughout the field, but growers were concerned about reduced productivity.  Dr. Eric Brennan, USDA/ARS Research Horticulturist and specialist in organic and climate-smart farming in Salinas, has been extending research done by Bugg et. al. (2008) showing that alyssum plants could be placed randomly in the fields at much reduced numbers and still maintain excellent aphid control without compromising productivity.”

The guiding principle that lifts SPM beyond IPM is that natural control is the end goal for successful transition. To help understand why this is so, we need to understand how living organisms communicate with each other in diversified agroecosystems. The interconnectedness has never been much of a feature in the practice of IPM. Nature exercises forces that must be part of the SPM knowledge base. The glimmer of knowledge available about heterospecific and conspecific communication in soil and above-ground food webs helps us appreciate pure entomological research AND respect intuitive ways of knowing. Our ignorance about natural phenomena is boundless compared to the tiny, usually biased glimmer we get from peer reviewed papers. 

For example, underlying plant-insect communication, we now know that by monitoring soil and especially also plant sap, practitioners can assess a plant’s health and capacity to resist pests. We can develop biological action levels for customized foliar nutrient and biostimulant sprays or side-dressings that shift the bioavailability of key nutrients to enhance plant defense mechanisms. Dr. Phillip A. Callahan spent decades researching and reporting on these phenomena showing that a healthy plant emits molecules and low energy electromagnetic waves that essentially repel pests while unhealthy, nutritionally out-of-balance plants attract pests. Dr. Tom Dykstra, a student of Dr. Callahan, founded a lab to continue this study and its application in agriculture.  

As I discussed in Part 6: “New knowledge for pest prevention” other research shows that molecules emitted by healthy plants continue for up to five days to protect neighboring plants [Sharma, et. al 2017]. Healthy plants can detect certain terpenoid molecules that cause an influx of calcium ions and membrane depolarization that can impact an herbivorous insect’s chewing ability.  It requires a lively soil biology for plants to access the calcium, sulfur and other minerals that are there in the soil and have such a widespread effect on the entire ecology including insect physiology. 

Moreover, complex plant communities of at least eight species support each other in the root zone to bump up nutrient cycling and fertility. Arbuscular mycorrhizal fungi around plant roots stimulate systemic tritrophic interactions in the soil ecology. Plants living in such lively root systems emit molecules that consistently direct insect behavior. For example,

“All plants synthesize a suite of several hundred terpenoid compounds with roles that include phytohormones, protein modification reagents, anti-oxidants, and more. Different plant lineages also synthesize hundreds of distinct terpenoids, with the total number of such specialized plant terpenoids estimated in the scores of thousands. Phylogenetically restricted terpenoids are implicated in defense or in the attraction of beneficial organisms.” [Pichersky and  Raguso, 2017].

These molecular and bioelectromagnetic phenomena of living ecosystems are important for carbon farming as well as the SPM knowledge base.

The implications of the complexity in biodiversity-based systems seem miraculous. It is a challenge to measure or model the complexity that should characterize living ecosystems. It is generally not a straight-line linear correlation between diversity and systemic functionality such as where tipping points of biodiversity accelerate all healthful functions in the plant, including the amount of deposition of soil organic carbon, nitrogen availability, and molecules involved in defense mechanisms. This hyphal/molecular/bioenergetic/epigenetic world is the boundary where SPM can leave IPM behind.

Board Certified in multiple entomology specialties, my mentor Everett Dietrick studied the scientific literature, attended and sometimes presented at top scientific conferences, and maintained close communication with researchers around the world, but he frequently said that his own repeated observations were equally applicable compared to the knowledge base available in the scientific community. From decades of sweeping with a standard sweepnet and the D-Vac Vacuum Insect Net that he co-invented, his comprehensive monitoring of a field in the farmscape context often yielded exceptional intuitive insights about population dynamics and strategies to tip the balance in favor of natural enemies. Strong training to develop deep curiosity about relationships in the natural world and personal capacity for other ways of knowing will make SPM more successful than IPM in pesticide use reduction. 


Altieri, Miguel A. and Clara I. Nicholls with Marlene A. Fritz. Handbook 7, Manage Insects on Your Farm – A Guide to Ecological Strategies. Sustainable Agriculture Research and Education (SARE), 2005. 

Bugg R.L., R.G. Colfer, W.E. Chaney, H.A. Smith, J. Cannon. 2008. Flower flies (Syrphidae) and other biological control agents for aphids in vegetable crops, University of California, Division of Agriculture and Natural Resources.

Callahan, Phillip (1965-1975). 36 published papers summarized on The Free Library page “Electromagnetic communication and olfaction in insects”.

Duru, M., Therond, O., Martin, G. et al. How to implement biodiversity-based agriculture to enhance ecosystem services: a review. Agron. Sustain. Dev. 35, 1259–1281 (2015).

Dykstra, T. How Insect Pests Identify Unhealthy Plants. Regenerative Agriculture Podcast with John Kempf. 

Headrick, David. The Future of Organic Insect Pest Management: Be a Better Entomologist or Pay for Someone Who Is, Insects 2021, 12(2), 140;

Nichols, Clara and Miguel Altieri, “Agroecology: contributions towards a renewed ecological foundation for pest management” in Ecological Theory and Integrated Pest Management Practice, ed Marcos Kogan, 1986.

Cate, James R. and Maureen Kuwano Hinkle, Integrated Pest Management: The Path of a Paradigm. Audubon Society, 1994.

National Academy of Science-National Research Council, Ecologically Based Pest Management (EBPM)-New Solutions for a New Century, 1996.

Pichersky, Eran and Robert A. Raguso, Why do plants produce so many terpenoid compounds? New Phytol 2018 Nov;220(3):692-702. doi: 10.1111/nph.14178.

Sharma, E., Anand G., & Kapoor, R. (2017). Terpenoids in plant and arbuscular mycorrhiza-reinforced defense against herbivorous insects. Annals of Botany, Volume 119, Issue 5, March 2017, Pages 791–801,

Southwood, T. R. E., and M. J. Way. 1970. Ecological background to pest management. Pages 6–28in R. L. Rabb and F. E. Guthrie, eds. Concepts of pest management. North Carolina State University, Raleigh, NC.

Therond, O., Duru, M., Roger-Estrade, J. et al. A new analytical framework of farming system and agriculture model diversities. A review. Agron. Sustain. Dev. 37, 21 (2017).

Van Lenteren, J., Sharad C. Phatak, James Tumlinson. “A Total System Approach to Sustainable Pest Management,” National Academy of Science – Proceedings paper,1997. 

Warnert J. 2009. The 50th anniversary of a great idea: Landmark article on “integrated control” considered “most important” pest control paper of 20th century. Calif Agr 63(4):160-161.


Our Vision for Successful SPM – Part 6: New knowledge for pest prevention

Ron Whitehurst, PCA and co-owner Rincon-Vitova Insectaries, Inc.

Our vision for successful Sustainable Pest Management is that UCCE Farm Advisors, farmers, PCAs, CCAs, and field scouts – all farm personnel – effectively monitor pests and biological control in a landscape approach for predicting populations and evaluating interventions appropriate to the farming system. They enhance biological control and eliminate or decrease pest problems below economic injury levels. 

We imagine future training and extension of biological control practices and tools available to everyone who is interested. They learn preventive cultural practices, habitat enhancement, and determination of biological action levels for colonization and/or augmentative release of natural enemies and/or application of biological and National Organic Program (NOP) approved pesticides.

PCAs and farmers can reduce pest problems and be more profitable. PCAs will guide farmers to build biodiversity-based systems, i.e. build soil, grow healthy plants that do not attract pests, build reservoirs of natural enemies and anticipate that pest population densities will stay below pesticide action levels resulting in no need for any pesticides because they do not want to disrupt the biological control. .

SPM EDUCATORS AT THE CENTER OF REGIONAL PLANNING:  All of our entomology professor friends who teach Pest Control Advisors (PCAs) cite the need for better support and communication with the Department of Pesticide Regulation and the California Department of Food and Agriculture. PCA’s must get Continuing Education Credits for learning from experts (now largely from the biocontrol industry) what they must know about the centrality of biological control and how it is achieved. 

Ruben Alarcon at CSU Channel Islands said entomology professors at CSUs and community colleges are sometimes brought in as an after-thought. It is usually Farm Advisors and product representatives offering Continuing Education Units (CEUs), not the professors teaching IPM or biological control. The knowledge needed is currently not approved for CEU course content.This must change immediately. 

If entomology professors would be consulted at the start of SPM curriculum development their advice would be to:

  • Include landscape level insect monitoring with a focus on natural enemies of key pests in the farmscape, invertebrate species identification, understanding pests and natural enemies as populations, insect movement (population dynamics), and then the more advanced training on determining pest to beneficial ratios and habitat enhancement for particular beneficials. To reiterate because this is so important, effective monitoring is at the landscape level and includes natural enemies as a prerequisite to biological, cultural and physical interventions.
  • Include protection of non-target animal species, including insectivorous birds, birds of prey, amphibians, fish and predatory mammals.  
  • Include understanding of naturally-occurring biological control and its importance for a healthy ecological system that doesn’t require the use of pesticides. 

RESEARCH AND EXTENSION IS IN DECLINE AND MUST BE ALMOST ENTIRELY REBUILT. While we are seeing a constant influx and threat of invasive species, warmer temperatures and extremes affecting pests and their natural enemies, biological control research is more needed than ever. There is an exponential need to train new biocontrol entomological scientists paid to study what farmers need to know. This is difficult when they depend on pesticide manufacturers for their research funding. 

Dr. Lynn LeBeck, the Executive Director of the Association of Natural Biocontrol Producers observes: 

“Our UC and CDFA biocontrol workforce are currently overextended just providing expertise for ongoing pest problems, but both are involved in “proactive” research initiatives for serious insect pests that are either being intercepted routinely or will be in the near future.  Positions vacant due to recent and pending retirements that are, and have had, biological control duties are not being refilled.”

With the very last few biocontrol entomology professors retiring and not being replaced, a huge priority must be put to rebuild the robust infrastructure for research to support SPM that is California’s legacy from before the influence of chemical pesticides. 

The history of our industry since the 1950’s has been in stark contrast to how it has developed in Europe and British Columbia where Dutch, British, Belgian and Canadian governments and agricultural universities helped their insectaries grow internationally. Most beneficial insects sold in the US are grown in those countries. The small amount of research done is by foreign insectaries in collaboration with their universities. Their business model sometimes puts a higher priority on sales over the multi-pronged approach to help farmers transition away from biological inputs. There can be similar conflicts of interest for biological and chemical input sales people. No Pest Control Advisors should be paid commission for their sales. Inputs of any kind are not in the farmer’s best interest if they don’t need them. There should be incentives for PCAs who sell advice to achieve successful programs with the least amount of products.  

Classical or “introduction” biological control is not given importance commensurate with what it achieved in the last century. It alone can quickly turn new pest invasions into non-pests as California’s state entomologists did effectively from 1907 until 1947 before the well-organized influence of the chemical pesticide industry. When plant-feeding insects arrive without their natural enemies, the most effective first strategy is to go to the native home of the pest and research to effectively reunite the natural enemies with their host insect. Most invasive pests are forgotten within one to four seasons as their natural enemies spread and come into balance.  

Biological input-based systems must be understood as the in-between part of the path from conventional chemicals towards biodiversity-based farming systems. They need help when colonization biocontrol or natural biocontrol is a little slow to build up. Augmentative biological control helps fill gaps apparent when monitoring development and maintenance of a biodiversity-based system. 

The California biocontrol industry has been largely either ignored, actively opposed or faced external competition. Rather than be supported to fill this role in transition away from chemical pesticides, it has survived by overcoming one regulatory, ignorant or corrupt UCCE advice, or market barrier after another. US insectaries have developed our knowledge base with the quiet help of a very few researchers, all of them now retired. Yet, we provide the products and services that work for people who do not want to use toxic pesticides. Worst of all, we must compete with some foreign insectary companies that have questionable sales tactics and product quality.

Our industry’s top product quality leaders and expert trainers have been mostly women developing their businesses in spite of the host of barriers too pervasive too describe here.

In the words of Dr. Lynn LeBeck, our industry association executive director:

“The commercial biocontrol producers and distributors in California (and nationwide) receive inquiries daily about how to use beneficial species in a myriad of cropping systems and sometimes all the data is just not extant for each detailed pest/crop/natural enemy. In addition organic production continues to increase in California, along with sustainable practices in general, but the skyrocketing acreage of a few crops in particular, one crop in particular, will overload resources.” 

Tight regulation and intensive testing of cannabis has resulted in some cannabis growers knowing more about non-toxic pest control than in any other crop. Similarly the horticulturists in zoos, arboreta and casinos who can’t or don’t want to use pesticides indoors have been highly observant and insightful biocontrol practitioners. When chemicals are not an option, because of regulations, risky exposures to people or captive wildlife, or personal preference of a manager, these people acquire the knowledge base to be successful. When chemicals are banned and not an option for anybody, then people in all sectors of agriculture and horticulture can learn and teach others to manage pests in biological input-based systems.

Research is needed in how much of what kind of biodiversity works best. Dr. Annemiek Schilder, Director of the Ventura County University of California Cooperative Extension stresses the importance of biological control for SPM and the need for an entirely new category for continuing education (CE) courses. She explains,

“Within this, there needs to be a focus on understanding ecological principles, interactions and population dynamics of beneficial and pest species, as well as the role of and how to measure farm biodiversity. We need to ask, is all biodiversity good or do we need specific components for a pest/disease-suppressive system?” 

Dr. Headrick has the same questions about how to know how much diversity is advisable. The most appropriate biodiversity may just be adding one new plant species to a system (doubling the number of species). He gives the example in sweet alyssum interplantings in Salinas valley lettuce to attract syrphid flies for aphid control that eliminated use of the worst pesticides in that chemical input-based farming system.

As we wean off from chemicals, Dr. Schilder asks: “There may be a temporary increase in pest pressure before a new balance is reached – how long does that take and how do you know you are going in the right direction? Understanding new action thresholds in all crops and varieties will require a substantial amount of research.” Who will do that?

Dr. Schilder has these additional thoughts about research needs:

“Much more testing and monitoring is needed to accurately assess pesticide burden in food and environment. Also, educating the public on relative pesticide exposure risk in the home or living environment vs. food.”

“There should be more funding for research efficacy trials. For many biological fungicides, data on efficacy on many crops and diseases are limited or lacking. More years of trials may be needed due to  variability due to variable weather conditions. We need additional efforts in finding ways to increase efficacy and reliability of existing materials, for instance with additives or blending products. For instance, from our research, we realized adding Nu-Film P (sticker-extender) helps protect bacteria-based products like Serenade, likely by reducing desiccation and UV-degradation.”

“Research is especially important for soilborne and vector-borne diseases where the vector is widespread and difficult to control. Clean (virus-tested) plants also can play a huge role in preventing diseases, especially viruses and virus-like pathogens. If viruses are absent, some insect vectors may not need the level of control that is required in the presence of viruses (National Clean Plant Network”. This will also relate to parasitic plants such as witch’s broom.

“We need research about spray technology–ways to improve coverage and efficacy as well as reduce pesticide burden and drift. Demonstrations are needed for already known technology.”

Biopesticide research, registration and extension is needed to meet rising demand. The EPA recognizes three major classes of biopesticides: Microbial Pesticides, Biochemical Pesticides, and Plant-Incorporated-Protectants (PIPs). Efficacy compares well with chemical pesticides and is safer for farmworkers and neighbors. Being biodegradable and with low volatiles, they do not pollute land, air or water and generally are low risk for beneficial insects and higher organisms and many are approved for use in organic farming. Just like with natural enemies for biological control, education is needed that they exist, that they work, that they do not pose risks as do chemical pesticides, where to get qualified advice, and where to buy them. 

As explained on the Marrone Bio Innovations website,

“Growers will try a new biopesticide product and compare it with their existing pest management programs in demonstration trials. Conducting demonstrations is the best, if not only way to gain adoption. In addition, University Extension researchers will also test pesticide products and provide their recommendations. Therefore, adoption can be faster as more field trials are conducted….In one California survey, growers and PCAs indicated that biopesticide companies should place a heavy emphasis on education in order to establish sustainable use of the product. They indicated that the companies should target specific markets, either by crop, pest or disease. In turn, companies should be very clear about the protection and value being provided to the grower.”

Biopesticides may support biological control but they are NOT biological control. The latter provides potentially more lasting benefits through classical (exploration and colonization) and augmentative biological control (releasing natural enemies to directly reduce pest populations). Biopesticides are important in the middle of the transition continuum–for biological input-based farming systems. There is a great need for proper education to build capacity for more comprehensive monitoring, integration of cultural practices, habitat enhancement, and the use of biocontrol agents and biopesticides that don’t disrupt natural biocontrol. All five of these features of biological input-based and biodiversity-based farming systems require an entirely different knowledge and skill set compared to planting pesticide-coated seeds and spraying or drenching chemicals. Biopesticides are very valuable tools, but biological control is the endgame.

Molecular biology and electromagnetic signals can help explain why biodiversity- based farming systems have few pests. After over 30 scientific papers explaining insect communication, Dr. Phillip Callahan’s discoveries remain outside of the knowledge base for pest management. Dr. Tom Dykstra founder of Dykstra Laboratories Inc. is continuing research showing how bioelectromagnetics explains the influence of electrical signaling on cell communication, growth and plant and animal health. Dr. Dykstra has a specialization in the complex physiological reasons why insects are attracted to dead, dying, or nutritionally poor, i.e. “sick” plants. He has shown measurable results with plant sap or leaf Brix readings reflecting plant nutrient composition, health and pest and disease decline in less than one season to improve soil, crop longevity, nutrient density and flavor, and profitability for producers. 

Illustration by Jan Dietrick inspired by image from Sharma, E., Anand G., & Kapoor, R. (2017). Terpenoids in plant and arbuscular mycorrhiza-reinforced defence against herbivorous insects.

Swiss scientists have also explained the electrical signals stimulated by insects chewing on plants. Wounds increase systemic plant hormone responses that can attract beneficial insects to attack the plant-chewing insect.  (Farmer, et. al. 2020) Another phenomenon in biodiversity-based systems is plant defensive strategies against herbivorous insects from terpenoids and symbiotic associations with arbuscular mycorrhizal fungi in healthy plants. Fungal hyphal networks in soil serve as electrical conduits facilitating the transfer of defense signals and terpenoids between conspecific and heterospecific plants. Terpenoids increase calcium ions and membrane depolarization causing a protective “priming memory” response lasting up to five days.(Sharma et. al. 2017). This is probably the tip of the iceberg in understanding why it is common that biodiversity-based farming systems are often pest-free and disease-free. We don’t have to have any more data than this to see how to design a Roadmap to achieve SPM goals.

Respect must be paid to all ways of knowing and learning for all SPM farm personnel. How can PCAs trained and experienced in determining chemical action levels learn new knowledge and skills to consider more and different variables when determining biological action levels? Then, also, how do PCAs help farmer clients see new options after they have been inundated by decades of pesticide propaganda? 

INRAE, the French National Research Institute for Agriculture, Food and Environment, is the number two agricultural institute in the world. It has evaluated various learning support tools including games that link principles and actions toward biodiversity-based farming to teach decision-making in situations of uncertainty associated with biodiversity-based farming systems. DPR and CDFA should welcome INRAE’s ideas and consultants in the development of curricula to support SPM.

A group training board game for learning decision-making about conservation ecology land management.

Research will help most current farmers to be more efficient and less polluting with agricultural chemicals being used at the chemical input-based part of the transition continuum. However, as learning and change take place, the need will shift to user-friendly decision-support systems which integrate up-to-date scientific knowledge for more biological inputs and biodiversity-based systems. 

Researchers at INRAE see the need for new teaching methodologies including game-based learning tools. The sociological factors are also critical. The Community Alliance for Family Farmers had an outstanding model in the 1990’s called “Lighthouse Farmer Network” that created a lively space for a monthly breakfast or lunch with a short presentation and give and take discussion with successful practitioners trying new sustainable practices. The participative discussion is much more important than the field day observations. Farmers can see what their neighbors are doing. They need to hear how it was approached and what happened. Certainly university experts giving talks is the least transformative pedagogy; more so when most of the research is in product trials where biological control is not one of the comparisons and the goal is resistance management comparing chemical, biopesticide, and genetically engineered plants. 

Duru, et. al. address the training needs:

“Developing biodiversity-based farming systems and multiservice landscapes raises questions about how to manage the “transformational” transition from specialized systems and simplified landscapes to well-established diversified ones. During this transition, variability in ecosystem services may increase greatly until slow variables reach states which provide ecosystem services at expected levels and degrees of biophysical resilience and stability. Uncertainties…may increase during this transition.” 

The transformation to increasingly biodiversity-based farming systems, where pest prevention is achieved through cultural management and habitat diversification to enhance natural biological control, requires a massive transformation in the educational and research infrastructure. Farmers and SPM educators are at the center of the work. Investment in farmer-led research must replace a research infrastructure that has been a marketing arm of the pesticide industry. This revival of the knowledge of biological control entomology with research and teaching personnel is vital. Diverse ways of knowing and learning and internal methods of validating knowledge must be respected along with the mainstream science of conservation and protection of biodiversity. 


Callahan, Phillip S. (1965-1975). 36 published papers summarized on Free Library “Electromagnetic communication and olfaction in insects”.

Callahan, Phillip S., 1975. Insect antennae with special reference to the mechanism of scent detection and the evolution of the sensilla. International Journal of Insect Morphology and Embryology, Vol 4, Issue 5,(381-430).

Duru et. al. (2015) How to implement biodiversity-based agriculture to enhance ecosystem services: a review, INRA Science & Impact, Agron, Sustain. Dev. 

Farmer, Edward E, Yong-Qiang Gao, Gioia Lenzoni, Jean-Luc Wolfender and Qian Wu, 2020. Wound- and mechanostimulated electrical signals control hormone responses, New Phytologist: 227(1037-1050)

Sharma, E., Anand G., & Kapoor, R. (2017). Terpenoids in plant and arbuscular mycorrhiza-reinforced defence against herbivorous insects. Annals of Botany, ncw 263.

Our Vision for Successful SPM – Part 5: Regional Focus 

Ron Whitehurst, PCA and co-owner Rincon-Vitova Insectaries, Inc.

The SPM Roadmap will be released by the California Department of Pesticide Regulation by the end of 2022. It will be a great step forward. To achieve the SPM goals, we believe the focus should be at a regional level. There is a parallel with federal IPM development with four USDA National Institute of Food and Agriculture Regional Centers that coordinate, enhance, and facilitate the flow of resources and information, including grants management, data acquisition and sharing, and accountability for resources. They help people organize IPM projects, create communications and learning forums, host webinars, moderate meetings, help state or local entities develop and disseminate information or whatever serves local goals. California Regional SPM Centers can play a similar role to expand and extend the knowledge base by such actions as follows:

  1. Reflect the continuum framework, i.e. chemical input-based to biological input-based to biodiversity-based farming systems,
  2. Research low-hazard and low-risk substitution tools necessary for transition,
  3. Facilitate community learning to integrate science, experience, and traditional and intuitive ways of knowing,
  4. Gather data for models that help teach the effects of agroecological practices on biodiversity and ecosystem services,
  5. Support learning for success in a biodiversity-based paradigm through seeing  the limits and false economies in the efficiency/substitution paradigm, 
  6. Facilitate learning that improves consultant and farmer decision-making in situations of uncertainty,  
  7. Improve communication between regulatory agencies and educators at public institutions with early engagement of educators of SPM in the decision process on aligned curricula and training of successful SPM practitioners,
  8. Include PCAs as active and respected players in the information pipeline especially in the area of field research, educational programs, and individualized grower assistance and follow up, and
  9. Showcase farms on their way to biodiversity-based systems that will attract added revenue from carbon and eco-credits. 

Among the opportunities with regional planning and programs, we’ll describe those that have not been discussed as much: Resource Conservation Districts, field scout training, regional food hubs and regional insectaries. 

Resource Conservation Districts are already a primary source of Technical Assistance and many employ people with backgrounds in agroecology and biodiversity conservation. There are 95 RCDs. Their boards of directors are from the region and tuned to local needs and resources. Their mission is natural resource conservation and learning how biodiversity-based farming systems support that mission through farmer-to-farmer learning and relevant farmer-directed research. They are an ideal focal point for stakeholders to consult and agree on strengths, needs, barriers and to make transparent decisions about how to distribute funding.

Wild Farm Alliance 2017 tool for organic farmers to work with RCDs to conserve biodiversity. 

Biological control field scout training is a needed area of development. Local colleges and universities, RCDs and the Cooperative Extension can collaborate to define the knowledge base for field scouts to monitor pest and natural enemy populations and apply biological control practices and tools, including installation and care of hedgerows, border plantings, interplantings, silvopasture, and agroforestry within an agroecological continuum framework. There are opportunities for inclusion and social equity values, for women, lower-income people, people of color, and especially farmworkers. Field scouting, like nursery work, is a path to employability in drug rehab programs. Some farmworkers have strong aptitude and desire to be field scouts. 

Francisco Cornejo Soms teaching Kevin Antongiovanni’s farm workers to scout for beneficial insects 1997

Regional food hubs are important for connecting farmers and ranchers with institutional buyers (restaurants, hospitals, schools, etc) and end consumers. They help farmers gain access to larger markets so they can focus more on farming and less on marketing, distribution, etc. Food hubs channel buyer needs and enable them to prioritize working with those farmers with organic or comparable certification. 

Regional insectaries have a long history in California. San Diego County Department of Agriculture was rearing Cryptolaemus for release into local lemon orchards at an insectary in Chula Vista in 1929 and other county insectaries followed. In the 1950s they were all funded by federal, state or county governments and then some by farmer cooperatives or pest control districts. The Fillmore Citrus Protective District (FCPD), a successful grower cooperative, had been formed to eradicate citrus pests, but an insectary to produce beneficial insects was added when the impracticality of eradication became evident. 

California State Insectarium. One of the world’s first insectaries built in 1907 at the capitol for collecting, breeding, and distributing beneficial insects to control fruit and vegetable pests. In 1923 most activities moved to the Citrus Experiment Station in Riverside.
Insect rearing cages in the state insectary over 100 years ago. . It is now a maintenance facility for Capitol Park in Sacramento.

Regional insectaries are an ideal focal point for collaboration in the training of both insectary workers and field scouts. Insectaries of the future must be grower-led cooperatives while benefiting from researchers to ensure uncompromised quality in biological control monitoring and interventions as well as products. In this model, regional cooperative insectaries can benefit the general community as well as farmers, assist with classical biological control projects, mass-rear and release augmentative biological control agents, and colonize and monitor released organisms. The membership of a regional insectary should democratically set priorities and plans about how to minimize toxic inputs, maximize grower economic sustainability, harmonize the urban-rural interface, and protect farmland. 

The ownership structure for regional insectaries best includes per acre member dues by growers, land-owners, and various districts, along with a financial contribution from local jurisdiction(s). The structure should have a check and balance on potential conflicting interests that may arise between insectary management, researchers and large growers. The manager must juggle the needs and strengths of a broad community of stakeholders to remain relevant and viable. All stakeholders must both inform and follow the lead of the  farmers, PCAs, farmworkers, and specialized agricultural workers and Field Scouts.  Grower-led regional insectaries are the way of the future. 

In my next post we’ll go deeper into how to teach and support Pest Control Advisors and field scouts to achieve biological control and help growers transition to less dependence on pesticides.  

Our Vision for Sustainable Pest Management – Part 4: Biological control action levels–examples from the field

by Ron Whitehurst, PCA and co-owner Rincon-Vitova Insectaries, Inc.

Pest Control Advisors (PCAs) make their decisions based on monitoring to determine an “action level” or “action threshold”. In other words, they look for signs that it is time to do something to prevent a serious pest problem. To align PCAs with the SPM goals, it is important that they understand the big difference between action levels for the conventional chemical input-based farms most of them are familiar with compared to farm systems that are either biological input-based, such as most organic acreage, or biodiversity-based. 

Treatment action levels on chemical input-based farms, of course, do not apply when chemicals are not an option. A new framework is needed for such farms. PCAs need training in determining “biological action levels”.  Entomology professor David Headrick asks his students at Cal Poly San Luis Obispo to think about two separate thresholds, one for chemicals and a different one for biological inputs. The following slide from his Biological Control class helps illustrate the need for early regular monitoring at low pest densities in order to time a natural enemy release to maintain the pest population at a low density. The timing of applications has to be carefully thought through. It is clear that the Economic Injury Level and the Chemical Control Action Threshold happen at a significantly higher pest density. 

Biological action threshold graph, Professor David Headrick, Cal Poly SLO Biological Control Course Lecture

As Dr. Headrick further explains, “Maintaining pest densities at low levels is most easily and effectively done with biological control agents. That is what they evolved to do – find prey when they’re scarce. It is also the most economically sustainable approach.”

Readers of “ACRES USA – A Voice for Ecological Agriculture” have been informed for decades about the potential for insects to find food and mates through subtle phenomena happening at low population densities. Dr. Philip S. Callahan, a regular contributor to ACRES USA, published Tuning In To Nature in 1975 describing experiments demonstrating insect behavior in response to low electromagnetic energies. He wrote, 

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

Biological control practitioners would never consider a biological action, such as releasing a few green lacewing larvae, when pest densities are high. Biological action levels must be earlier, at the first sign of a key pest in the season, when successful biological control is achievable. Consideration is also given to various cultural practices that minimize disruption of biological control. Long-range planning for habitat enhancement is another consideration.  Enhancing habitat in the long term can maintain pest levels at such low densities that monitoring does not need to be as in-depth or as frequent as field scouting shows no sign of reaching a biological action level. The focus of field scouting evolves to be more about continuing to enhance and monitor natural biological control.

Biological control entomology intersects not only with agroecology, including soil ecology, conservation biology and population dynamics, but also increasingly with molecular biology and insect-insect and plant-insect communication. Farmers and their Pest Control Advisors will need to be observant of population dynamics at the landscape scale and how insect and plant volatiles affect plant defenses and insect behavior. 

Dr. Joseph Patt with the USDA-ARS received doctorate degrees in both entomology and botany. His research on releasing parasitoid wasps for control Colorado potato beetle in eggplant led him to measure the accessibility of nectar in different potential habitat plants to make sure there was enough space in the floral architecture for the large heads of the wasps that the New Jersey State Insectary produced. Without nectar, the number of required wasps was unaffordable. By comparing 15 different plants and choosing to plant seed dill and coriander that have many flowers with open nectaries, he ensured adequate nutrition for wasp searchability and reproduction. This minimized the number of wasps that had to be mass-produced for a cost-effective program of one row of floral habitat every tenth row. Unfortunately farmers dropped the biological program when the EPA registered a new chemistry with Colorado potato beetle in eggplant on the label. Research funding in this area also disappeared. 

Diagrammatic representation in lateral view of the floral architectures on which E. puttleri and P. foveolatus were evaluated showing position of the nectar glands (in black) in relation to the other floral parts: (1) Umbels with exposed nectaries; (2) Cyanthia with exposed nectaries; (3) Umbels with partially hidden nectaries; (4) Cup- shaped flowers with partially hidden nectaries; (5) Capitula with hidden nectaries. Wasps are drawn to scale and are 3 mm long. Patt, et. al. 1997.

Many observations go into determining the presence of effective natural biological control. However, Pest Control Advisor training has been nested within a Production Agriculture curriculum, isolated from the sciences that explain population dynamics, and insect and plant physiology, biochemistry and electromagnetic communication to enhance biological control. To be aligned with SPM, the curriculum for PCAs must be equally nested within agroecology and the sciences that explain plant defenses and insect and mite behavior.

Dr. Headrick motivates his students to learn how to manage pests on regenerative organic farms by reminding them of the unsustainability of conventional chemical control. He tells them, “Chemicals are great for instant gratification, but not for long-term success in pest management.” This fact leads his students into the whole subject of pesticide resistance.

To be able to forecast whether population densities are approaching action levels, there is much to learn. Then, they have to be able to help farmers understand these concepts. Much research is needed for both areas of pedagogy. Scientists in France are developing learning models and games that teach decision-making about biological action levels. With such limited current training for PCAs, an entry level field scout requires at least two years of mentored field experience to learn basic skills to recognize action levels. Scouting in a variety of crops and farming systems is more challenging. It takes more years to be able to perceive the population dynamics and consider alternative cultural practices and cost-effective, manageable habitat enhancements and communicate with farmers to understand the options.

I enjoy those experiences when someone buys a rundown chemical farm and contacts me wanting to be organic. We start early in the fall to plan. I now know that measuring the upper and lower levels of compaction levels in the soil is critical to deciding on tillage. What characteristics are needed in a ground cover? Is good quality compost available?  Are ants likely to interfere with biological control? Where should this farm start with permanent habitat installations?

Early in the growing season there might be indications that one or more colonizations in perennial crops might help. Pest populations often stay so low that a biological action threshold is never reached and there is no need for augmentative releases or “treatments” with natural enemies. 

Here are a few examples to illustrate how biological control scouts determine a biological action level. 

Farm & location: Sanford, Santa Rosa Rd, Buellton

Size & farmscape: 12 acres between road and steep hillside, across the road from organic farm and Santa Ynez River, east-west river valley 16 miles from coast, diurnal breeze

Farming system, prior crop(s) & years in transition: at least a decade of chemical input-based lima beans, year 1 transition to organic

Crop(s) and key pest(s) & economic threshold: lima beans, two-spotted spider mite, in past would defoliate if not sprayed at least once, usually 3-4 times with conventional miticides

Cultural adjustments: none

Habitat enhancements: two interplantings ‘Beneficial Blend” with 20+ species plus weedy alfalfa, successional sweet corn, sorghum and sunflowers, perpendicular to prevailing westerly wind, 1) 30 ft from west end, 10 ft wide X 40’ long, 2) middle of 12 ac block, 10’ wide X 80’ long, 

Natural enemy colonizations: none

Monitoring method(s) and frequency: visual appearance of necrosis from spider mite damage, live mites and eggs, weekly across in 3-4 places and along perimeter 

Biological action level: monitoring showed the biological control from the interplantings protected most of the block except the south border on the east end  edges along the hill and drive road becoming infested; without natural enemy release, if there were hot, dry weather the mites could spread into the middle of the field protected by the biological control from the interplantings; mites could blow up requiring a spray to protect the whole block 

Action & result: two weekly releases of Galandromus occidentalis and green lacewing along the south border of the eastern half of the block brought the pest mites under control 

Farm & location: Dairy barn outside of Gunnison, Colorado

Size & farmscape: 10 cows, 1,000 sf open front, 3-sided, free-stall barn; manure moved daily to compost yard

Farming system, prior crop(s) & years of transition: organic cows over ten years

Crop(s), key pest(s) & economic threshold: houseflies annoy cows, reduce milk output

Cultural adjustments: more frequent clean-out, bucket trap near compost

Habitat enhancements: n/a

Natural enemy colonizations: monthly releases 10,000 fly parasites beginning at first sign of flies

Monitoring method(s) and frequency: 3X5 index “spot cards” counted weekly. Start with 4 cards and reduce to as low as 2 cards if counts are within 10%. Place one on the warm side and one on the cool side, one upwind and one downwind if there are differences.

Biological action level: average 100 spots/card, over 65’F so flies are active

Action & result: balEnce Fly Spray (beneficial fungus Beauveria bassiana) on surfaces; average spots/wk below 20.

Farm & location: Anonymous, Edna Valley, San Luis Obispo County

Size & farmscape:  Two fields separated by a seasonal creek: 40 acres and 35 acres, sandy loam soil.

Farming system, prior crop(s) & years of transition:  Standard, previously farmed as vegetables, conventional production, but no synthetic pesticides used.  I was hired to manage the crop start to finish using only biological control.  

Crop(s), key pest(s) & economic threshold:  Hemp for CBD, key pests:  western flower thrips, spidermites, noctuid caterpillars, botrytis.  CBD products are supposed to be made from plants without any pesticide residues and with as few contaminants as possible.  In this case having biological control agents on the plant surfaces at the time of harvest was deemed acceptable for the CBD extraction process.

Cultural adjustments:  Typical row crop approach, plastic mulch on beds, 40 inches on center, transplants at 2 foot spacing.  Transplants grown in a greenhouse from certified seeds.

Habitat enhancements: None.

Natural enemy colonizations:  In the greenhouse setting, the following natural enemies were released at standard rates so that they were actively foraging and reproducing on plants before they were placed in the field – a “pre-transplant inoculum”: Orius releases were made for thrips, Stratiolaelaps scimitus (Hypoaspis miles) was inoculated onto the transplant container soil surface for fungus gnats, lacewing eggs for whiteflies and small lepidoptera and Aphidoletes aphidimyza for aphids.  

In the field, subsequent releases were made based on monitoring.  Spot treatments of Neoseiulus californicus was made for spidermite control.  Bacillus thuringiensis was applied as a spray for caterpillar control.

Monitoring method(s) and frequency: Greenhouses were monitored with visual inspections, tap method and yellow sticky cards.  Monitoring was done once a week until plants reached about 8 inches tall, then twice a week until transplanted.  

Fields were monitored with visual inspection and beat sheet.  

Field monitoring was conducted once a week along rows, every 6th row but different rows each time, and always checking the first three upwind rows and two downwind rows each time.  

Biological action level:  All biological control agent releases (greenhouse and field) were made only if the target pest was present.  Thresholds were set “at first sight of pest”, with the idea that pests at low population densities are more easily controlled.  Most mite issues started on the upwind rows, predatory mites were applied as spot treatments.  N. californicus was chosen due to the hot, dry conditions and its ability to feed on prey other than T. urticae.  Bt sprays were applied to the entire field as soon as adult moths were observed being disturbed by the beat sheet monitoring methods.  Lepidopteran eggs were impossible to locate on the dense and trichome-laden foliage and flowers and waiting until feeding damage was readily observed was too late to gain control of the caterpillars.  The concern with caterpillar feeding was not so much the foliage, but the flowers.  When caterpillars fed in the dense flower clusters, they were virtually impossible to see and the feeding damage resulted in Botrytis infections.  Botrytis is a devastating fungal pest and will ruin a crop because it negatively affects the terpenoid extractions.  Closer to harvest, Bt sprays were conducted once a week as per the growers request.  

Action & result: I achieved excellent results with a 100% harvestable crop.  The greenhouse inoculation program was an effective and cost-efficient approach to having natural enemies evenly spread throughout the field and working on pest populations before full exposure to field conditions and new pest populations.  The approach of applying biological control agents on mature plants in the field can often lead to losing many of them during the process.  The Bt sprays were effective, but caterpillar control needs to be re-evaluated and diversified to avoid resistance.  Additionally, making spray applications on the dense flowers can itself lead to conditions that aid fungal growth.  Consistent, systematic, monitoring from crop onset and application of appropriate biological control agents when pest populations were extremely low was the recipe for success.  

Farm & location: Millennium Grove, Santa Paula, CA

Size & farmscape: 5 acres, landfill on long side

Farming system, prior crop(s) & years of transition: biological input-based;  sandy rocky, not organic

Crop(s), key pest(s) & economic threshold: Haas avocado (flowers Feb-May), persea mite; 8% leaf damage can cause defoliation

Cultural adjustments: 3-6 inches mulch, seaweed+high quality compost extract foliar 5X between Feb & June (flowering period), no artificial nitrogen or mineral fertigation 

Habitat enhancements: one “predator food station” every 8-12 trees, 1-2 stations/acre (with 12-20 plants of corn/acre (early, middle, late varieties planted monthly in April, May & June with Johnson grass and/or native creeping ryegrass or other grass with summer through fall flowering); maintain by watering each monitoring visit, cutting some bloom from grass patches when flowers are done to stimulate new flowering for continuous production of pollen blowing onto surrounding trees to maximize reproduction of predator mites

Natural enemy colonizations: none

Monitoring method(s) and frequency: spring & summer every other week, fall & winter monthly. Machlitt method: number of random leaves with one or more persea mite.  Number of Euseius hibisci  mites feeding on Persea mites on 50 random leaves 

Biological action level: Release N. californicus (Nc) predator mites by blower. Number depends on month, heat, humidity: 

  • April-June below 85’F, 25 leaves out of 50 w 1+ Persea, <10 Euseius: 100 Nc/tree first release
  • July-Sept below 85’F,  same levels as above: 150 Nc/tree first release
  • Forecast of Santa Ana winds (<10% humidity):same levels as above:  200-250  Nc/tree if first release
  • Forecast of heat wave over 100’F for 3+ days: no release since Persea die

Action & result: One June release of 100 Nc/tree resulted in <2% leaf damage; monitoring in August showed 15 Euseius/50 leaves; some corn and grass still producing pollen; Persea stayed below action level 

Millennium Grove. Trials of cover crops, grasses, weeds, and occasional corn hills to supply pollen to increase reproduction of predatory mites.

Farm & location: Christmas tree farm, Decatur, Illinois

Size & farmscape: 50 acres edge suburb, riparian native woodland east side, monocropped farm blocks three sides 

Farming system, prior crop(s) & years of transition: biological input-based Christmas trees for 20+ years

Crop(s), key pest(s) & economic threshold: 30 acres in Mugu and Scotch pine trees, pine needle scale, average 5 covered scales per needle on 10% of needles after pruning out the current year’s infested needles 

Cultural adjustments: Pruning infested branches

Habitat enhancements: permanent border of pine trees, mowed grass cover crop, one strip native flowering annuals per ten acres east-west

Natural enemy colonizations: none; Chilocorus lady beetles well established

Monitoring method(s) and frequency: double-sided tape around branch on warmest (south) side of tree, red nymph crawlers stuck on tape or on white paper on a clipboard when branch is hit over the paper once

Biological action level: average more than 1 nymph per tape or on white paper, release Lindorus lopanthae predatory beetles with 40/ac 1st release, 30/ac 2nd release two weeks later, and 1 or 2 more releases if crawlers continue to appear

Action & result: 2022 released total of 100 Lindorus per acre in four releases over 5 weeks during crawler emergence prevented development of noticeable armored scale


Patt, Joseph, George Hamilton, James Lashomb, 1997. Foraging success of parasitoid wasps on flowers: Interplay of insect morphology, floral architecture and searching behavior  Entomologia Experimentalis et Applicata, vol 83


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