Posts Tagged 'SPM'

Our Vision for Sustainable Pest Management Part 2: Defining how SPM actions relate to each other- Rev 9/23/22 

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


We sometimes hear people talk about “biologicals” as if the word is interchangeable with biological control. It is an example of lack of understanding about the full meaning of biological control in the transition away from conventional chemical control. Agreement on the vocabulary for agroecology, insect ecology and biological control is essential for productive conversations and successful pest management. 

We like to use definitions from Biological Control by Natural Enemies (1974) by Paul DeBach modified by Huffacker and Dahlston to include antagonists of plant pathogens. These align with those used by David Headrick, Professor of Agricultural Entomology, Biological Control of Agricultural Pests, Vertebrate and Insect Pest Management in the Plant Protection Science Program at Cal Poly San Luis Obispo. 

In a recent personal communication, Dr. Headrick wrote:

“Definitions are critically important, and I am particularly frustrated by the blurring of the lines on what is and isn’t biological control throughout the industry.  I agree with the definitions of biological control that you have provided below.  It is important to consider the difference between natural control and human-aided biological control, with biological control being the use of populations of natural enemies (imported or naturally occurring) to control or reduce populations of pests with various methods.”

Our mentor Deke’s understanding about biological control drew on countless hours of discussions over many years including on skin-diving trips. Here are UC entomology researchers Everett “Deke” Dietrick (l) with Paul DeBach (center) and Blair Bartlett (r), Moro Beach ~1948.

Our mentor Everett J. “Deke” Dietrick favored Paul DeBach’s terms and ideas. Deke, Paul, Blair Bartlett and a few other eminent biocontrol entomologists shared a love of not just biological control, but also enjoyed a long friendship and lively discussions while searching for the perfect skin diving cove between Laguna and Cabo Pulmo. Such conversations animated their lunch hour handball games at the Riverside Citrus Experiment Station (now UCR) as well as field trips including with Evert Schlinger, Robert van den Bosch, Fred Legner, Dan Gonzales, and others. This cadre of biocontrol entomologists helped Deke develop the clarity and confidence to leave the University of California and become the first consultant in California relying solely on biological control by natural enemies to manage pests.  This was before the invention of the term “IPM or Integrated Pest Management”. He called what he and enthusiastic consultant associates did for farmers “Supervised Control”. 

The birth of IPM and EBPM (Ecological-Based Pest Management) and the ‘Path of a Paradigm’ will be a later deep dive in this series for those interested in a sufficiently broad conceptual framework for talking about transition. But first, let’s agree on the terminology.   


Biological control, when considered from the ecological viewpoint as a phase of natural control, can be defined as the action of parasites, predators, and pathogens and antagonists in maintaining another organism’s population density at a lower average than would occur in their absence. [DeBach, 1974]

  • Note:  It can be measured, human manipulation is not implicit and it does not include plant selection for resistance to pests.  Biological control by natural enemies is central to transition from chemical input-dependent systems. When monitoring shows that there are enough natural enemies so that biological control is working, the complexity of phenomena may be too costly to measure and assess what actions are critical. The greater the biodiversity, the greater the complexity of interactions, the greater likelihood of a good ratio of natural enemy populations over pest populations. (See monitoring)

Applied biological control is the study, importation, conservation, and augmentation of natural enemies for the regulation of population densities of other organism’s abundance below the level of economic injury. Applied biological control can be achieved in differing degrees of economic importance which have been distinguished as partial, substantial or complete.

Natural control (sometimes called naturally occurring biological control) may be defined as the regulation of populations within certain more or less regular upper and lower limits over a period of time by any one or any combination of natural factors. [DeBach, 1974] 

Augmentative biological control is the mass collecting or rearing and release of natural enemies (predators, parasites and pathogens) to control pests in a timely seasonal or inundative manner to prevent population increases, or to suppress a pest population, sometimes called inundative releases to differentiate from colonizations.

Classical or importation biological control is the foreign exploration, importation and colonization of natural enemies of a pest of exotic origin that lacks natural enemies to suppress their populations. 

Conservation biological control is about conserving natural enemies either by reduction/elimination of toxic pesticides or enhancing/modifying the environment to invoke/enhance/supplement natural control.  

  • Note: This is a useful definition that covers all of the newer terms like ecological pest management in regenerative organic agriculture, farmscaping, biodiversity-based agriculture, and so on, that work by conserving biological control.  

Biological control monitoring consists of skills and tools to assess the ratio of the pest and natural enemy populations to indicate whether biological control is increasing or decreasing. Each farming and cropping system has relevant observable phenomena that can be identified, counted, recorded, and compared with samples from other sites or time scales. Sometimes visual inspection, sticky or pheromone traps are sufficient. Sometimes a sweep net is essential and sometimes a vacuum insect net is the only way to observe the presence of important natural enemies. Identification of organisms follows monitoring of the insect ecology. The required accuracy in counting sample contents and the precision in identification depends on the level of consequence for cost-effective decision-making. 

Biological action level is the density of key pests relative to the biological control at a particular stage in the crop cycle and the pest cycle that suggests that the application of one or more natural enemies will help ensure that the pest population stays below economic injury levels.

  • Note: David Headrick explains that the timing of applications of natural enemies, i.e. the biological control action levels, has to be carefully thought through and monitoring has to be more intensive than for chemical control action levels.

Economic injury level is the number of insects (amount of injury) that will cause yield losses equal to the cost of insect management – generally used for pesticide application decisions. 

Chemical action level or threshold is the pest density at which the pesticide application should be done to prevent an increasing pest population from reaching the economic injury level. 

Beneficial organisms in the context of SPM are predators, parasites, and pathogens and their antagonists contributing to biological control. The term does not typically include fish, amphibians, birds, reptiles, and mammals, but it can.

Natural enemies in the context of SPM refers collectively to all of the predators, parasites, and pathogens and their antagonists that reduce numbers of pest insects and mites, and may include fish, amphibians, birds, reptiles, and mammals, e.g. bats and other rodents. Organisms can have key roles as predators and may also transport beneficial parasites and pathogens in biodiversity-based farming systems. [UC-IPM

Biologicals are products derived from naturally occurring microorganisms, plant extracts, insects or other organic matter that may be categorized as 1) biostimulants to enhance plant growth and productivity, 2) biopesticides to protect plants from pests, or 3) biofertility or plant nutrition products.  

Note: A “biological” is an input whereas “biological control” is its larger sense a characteristic of the ecosystem. Biologicals are often products viewed as alternatives to chemical pesticides. They may still disrupt biological control by negative impacts on natural enemies.

Biopesticides are certain types of pesticides, 1) biochemicals, 2) microbials, and 3) Plant-Incorporated-Protectants (PIPs) derived from such natural materials as animals, plants, bacteria, and certain minerals.  [US-EPA] 

Biological control entomology is the applied branch of zoological study dealing with  insects and loosely including other arthropods (e.g. spiders and mites) for the purpose of controlling pests through conservation, importation, colonization and augmentation of beneficial organisms. Biological control deals principally with insects because most pest species are insects and most insect pests have natural enemies.

Biological control phytopathology and entomo-pathology are branches of study dealing respectively with the interaction between pathogens and plants and between pathogens and insects.

Biodiversity-based farming systems rely on re-designing the site-, space-, and time-specific practices and production approaches to create a high biological diversification and intensification. It is knowledge-intensive with outcomes of greater productivity and fertility from less exogenous inputs, and greater resilience to external impacts. This approach introduces a paradigm shift in expectations. It requires integration of interconnected processes, including influences of chemicals and/or low and very low short low-frequency waves, as well as integration of organization levels in ecological systems, such as landscape level populations and communities. [Duru, et. al. 2015]

Biological input-based farming systems rely on external biological more than chemical inputs to increase efficiency in combination with incremental substitution changes or system adaptations, such as organic fertilizers, and low-risk biological and botanical pesticides that mimic natural phenomena in biodiverse agroecosystems. This approach may integrate conservation, colonization and/or augmentation biological control [Duru, et. al. 2015]

Chemical input-based farming systems rely on external chemical inputs and technologies for improved efficiency and yield, that often include the use of Haber-Bosch-based nitrogen, potassium, and phosphorus fertilizers and chemical pesticides that optimize yield while limiting pollution. This approach may integrate conservation, colonization and/or augmentation biological control. Prohibition of nitrogen run-off may lead to use of cover crops in sensitive areas or in landscape features to prevent water pollution. Larger farm sizes and economies of scale may be required to afford the cost of technologies, such as sensors, spray equipment with targeting ability, drones, robots, satellites, cultivars and animal breeds. [Duru, et. al. 2015]

Efficiency/substitution approaches are economically driven practices within a chemical or biological input-based farming system. They are often top-down, developed by companies selling products or advisors that have evaluated products to meet expectations of greater profits by greater efficiency and use of technologies and innovations that reduce costs. [Duru, et. al. 2015]

Integrated Pest Management (IPM) IPM is an ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties. Pesticides are used only after monitoring indicates they are needed according to established guidelines, and treatments are made with the goal of removing only the target organism. Pest control materials are selected and applied in a manner that minimizes risks to human health, beneficial and nontarget organisms, and the environment. [UC-IPM]

Sustainable Pest Management (SPM) is an agroecological approach within a spectrum of continual improvement to prevent, minimize, and manage pests in ways that protect human health and are environmentally sound, socially equitable and just, and economically viable. Pests are managed by combining biological, cultural, physical (including the use of new technologies that can improve detection, precise interventions, and plant resistance to pests), and, only when absolutely necessary, chemical tools, in a way that minimizes economic, health, and environmental risks.

Organic as a labeling term indicates that the food or other agricultural product has been produced by approved methods. USDA organic regulations require the application of a set of cultural, biological, and mechanical practices that foster cycling of on-farm resources, promote ecological balance, and conserve biodiversity. These include maintaining or enhancing soil and water quality; conserving wetlands, woodlands, and wildlife; and avoiding use of synthetic fertilizers or pesticides, sewage sludge, irradiation, and genetic engineering.

Regenerative agriculture has been called a land management philosophy. It involves the development of biodiversity-based farming systems focused on agroecological principles and practices that 

  • minimize soil disturbance; 
  • cover soil by mulching and multi-species cover crops or pasturage to prevent erosion and minimize weed growth; 
  • rotate crops to increase nutrient cycling, soil fertility, and water retention; 
  • increase plant diversity to conserve wildlife, pollinators and biological control and  increase soil microbial abundance; 
  • keep living roots in the soil as much as possible to protect soil microbes and retain water and nutrients; and, 
  • integrate animals into the farm as much as possible that adds nutrients and builds soil organic matter.

It draws on knowledge from agroecology,  agroforestry, organic practices, and holistic and rotational grazing. It offers increased yields and profit, improved watersheds, and enhanced ecosystem services, such as restoration of small water cycles, carbon drawdown and potential for accreditation for carbon and “eco” credits, resilience to climate instability, and better health and vitality for farming communities.

Regenerative organic encompasses organic farming and then raises the bar, prioritizing building soil health as a way to fight climate change. A holistic system, regenerative organic sees the well-being of earth, humans and animals as interconnected. High standards for animal and worker welfare are critical. It does not mean that the farm has Regenerative Organic Certification; it means that the farm is striving to apply these principles. [Patagonia Provisions]

Regenerative Organic Certification (ROC) is a label that can be added to organic certification for farms that meet higher standards in three areas: Soil Health & Land Management, Animal Welfare, and Social Fairness. Producers can choose to meet a beginning set of criteria (Bronze), an intermediate (Silver) or the highest achievable level of regenerative organic production (Gold). There are additional fees for ROC certification.

Real Organic Project (ROP) is a label that can be added to organic certification for farms that grow their plants in healthy, living soil and raise their animals humanely and on pasture to help consumers differentiate farms that are growing their animals and crops to both the letter and spirit of the certified organic standards. There is no fee for ROP certification.

Demeter Biodynamic Certification is a label that indicates that a comprehensive organic method has been used that requires the creation and management of a closed system minimally dependent on imported materials, and instead meets its needs from the living dynamics of the farm itself. The standard reflects the characteristics  of biodiversity-based farming systems. There are fees to become certified.


DeBach, P., Biological Control by Natural Enemies, Cambridge University Press, 1974.

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).

Huffaker, C.B. and D. L. Dahlsten, “Scope and Significance of Biological Control”, in Bellows, T. S. and T. W. Fisher, Ed: Handbook of Biological Control, Academic Press, 1999.


Our Vision for Successful Sustainable Pest Management – Part 1: The Centrality of Insect Biodiversity 

by Ron Whitehurst, PCA, with Jan Dietrick, MPH, Co-owners Rincon-Vitova Insectaries, Inc.

Everett J. “Deke” Dietrick
Robert van den Bosch

Appreciation to Deke & Van

We draw on what we learned from our mentor, Jan’s father, Everett J. “Deke” Dietrick, and Robert “Van” van den Bosch who dedicated their lives to biological control of pests, as we envision how SPM can work

In his memoirs Deke wrote: “There were such political challenges to carrying out the research I was doing to promote biological control by natural enemies that at this critical juncture in 1960 when modern organic chemistry was leading the “war on bugs”, I saw an opportunity to start a professional consulting service that sold pest management based on biological control. Having spent 15 years in classical biological control research, I was ready to try to reach growers with the news that biological methods are better than chemical methods.”  

Van summed it up: “The evolution of a rational pest-control strategy very much depends upon the outcome of this conflict…between those who are seeking change and those who want things to remain as they are.” From The Pesticide Conspiracy (1978) p. 91.

Part 1 – The Centrality of Insect Biodiversity

I am honored to have the opportunity to serve on the Sustainable Pest Management (SPM) Work Group advising the California Department of Pesticide Regulation on the development of a Roadmap to transition away from reliance on toxic pesticides. The group has 25 members. There are a few people like me who manage pests without chemical pesticides. There are also several experts in Integrated Pest Management, several who struggle with the idea of losing access to chemical pesticides, several representing farmworkers and a couple representatives of indigenous stakeholders, in this case Pomo Indians and another tribe, as well as toxicology exposure scientists, biodiversity and food protectors, and Houston Wilson, Director of the new University of California Organic Agriculture Institute. 

Good news! After well over a year of meetings, the consensus Roadmap is starting to come together. Meanwhile I have been collecting more ideas from friends about what it needs to be successful. Thanks to 22 friends who took time to give me some feedback, we have a great collection of important ideas that I’m forwarding to the SPM Work Group. Entomologists (professors and researchers) shared what I believe are the most important ideas. Four of them teach biological control to Pest Control Advisors (PCAs) and have a lot to say! Several PCAs and consulting agroecologists shared insights. The thoughts from organic farmer and field research friends Phil McGrath, Larry Jacobs, Steve Sprinkle, and Arianna Bozzolo of Rodale Institute confirm what we know to be true about the benefits and that farmers need help. I’m especially grateful to Annemiek Schilder at the Ventura County UC Cooperative Extension; Jo Ann Baumgartner, Director of Wild Farm Alliance; Daniel Gluesenkamp, Executive Director, California Institute for Biodiversity; and Nik Bertulis, Co-Founder California Center for Natural History, also a Permaculture Designer and Teacher, for their detailed suggestions. If you want to see the discussion draft or just have thoughts about what’s in this blog, let me know.

Out of the gate, my biological control friends agree that Sustainable Pest Management or SPM is a big step up from Integrated Pest management or IPM because it aims for long-term prevention of pests and their damage in a framework of increasing biodiversity. It is achieved by conservation biological control (including habitat enhancement and adjustments in cultural practices) as well as consideration of mechanical controls and use of resistant plant varieties. Chemical pesticides are used ONLY when other methods aren’t adequately managing pest populations. Definitions are critically important, which I’ll post about next. The Roadmap is easier to navigate when we understand what others are talking about! 

Our biological control sector lifts up the importance of increasing biodiversity–not just because it is the way to wean off of toxic pesticides–but also because we want the Roadmap to offer a positive vision of increasingly biodiverse farming systems that are more resilient with fewer problems and less costly inputs. This is what agroecology looks like. 

Experts in agroecology and biological control agree that the goal of the Roadmap is to move along a biodiversity continuum with metrics and targets for both below and above ground biodiversity. Jo Ann Baumgartner has already been traveling this road more on the above-ground level. Check out the publications by the Wild Farm Alliance that help organic farmers comply with the USDA National Organic Standards. The organic law requires that organic farms “foster cycling of resources, promote ecological balance, and conserve biodiversity.” Jo Ann published Positive Organic Indicators and Red Flags–Inspecting for Natural Resources and Biodiversity on Farms to standardize concepts for increasing compliance with the organic standard. Her work is expandable beyond organic to SPM. Another Wild Farm Alliance publication How to Conserve Biodiversity on the Farm: Actions to Take on a Continuum from Simple to Complex suggests what we know from science, that with complexity there is more biological control of pests. I plan on diving dive into this in my seventh post in this series. 

Organic farmers are leading the way to SPM. Every crop in California can be grown organically without artificial toxic inputs. Organic and especially regenerative organic farms have greater resilience to drought and floods and tend to reduce and sometimes nearly eliminate the need for costly fertilizer and pest control. Weeding, mulching, and the possible need for on-farm composting can require more labor. The farmer might need new types of equipment and inputs to build healthier soil and suppress pests, but before long the farm is more profitable and the benefits become evident. The first couple or three seasons building biological balance might keep the farmer awake at night, but, the way one of our customers put it, “Farming is fun again when I left the spray rig in the barn.”  For most organic farms, the focus is on increasing biodiversity within the root zone of the crop plants and then learning what kinds of above-ground biodiversity fit with the cropping system and meet the particular goals. 

The first idea from a few friends was about the necessity for regular landscape scale biodiversity monitoring as part of the principles and practice of agroecology. As Daniel Gluesenkamp, Director of California Institute for Biodiversity (CIB) explains, “We currently don’t even have a baseline inventory for insects. We don’t know how many insect species occur in California, maybe 50,000 to 200,000 with only 40,000 to 60,000 having been described by science.  We have no maps or good site-specific characterizations. We are blind. There are technical challenges in catching/viewing insects, especially the many tiny forms.”  We also need to know the negative impacts that affect non-target vertebrate species–insectivorous birds, birds of prey, amphibians, fish, and predatory mammals that is documented in this film: The great death of insects | DW Documentary. . We want a robust monitoring program rolling out in 2023. Numeric goals and target dates for establishing baselines and databases and monitoring infrastructure must be a top priority in the Roadmap.

CIB is doing DNA barcoding to establish baselines for insects and the Dietrick Institute for Applied Insect Ecology specializes in training women, farmworkers, and students in monitoring insect populations where farmers have installed habitat enhancements for natural enemies. The California Center for Natural History can pilot and train teachers and NGOs to organize citizen scientists to help count non-target animal species. Getting baselines is a costly initial undertaking, whereas the on-going monitoring will not be expensive. What areas need the most help? How well are we restoring biodiversity in priority regions? How does that correlate with pest pressures?

From United Nations Environment Programme, Foresight Brief No. 011, 2019, 
We are “Losing the Little Things that Run the World”

This important work to inventory California’s insects builds on my father-in-law, Everett (Deke) Dietrick’s work with Robert van den Bosch from 1953 to 1960 in the University of California Department of Biological Control cataloging all the insects in an alfalfa field using sweep nets, vacuum nets, and soil/duff samples. Dr. van den Bosch and Everett Dietrick observed that most of the insects in California agriculture could be found in untreated perennial alfalfa fields.

Working on the SPM Roadmap gives me hope. I’m excited to share in upcoming posts more about what I’ve learned with the Work Group. My partner Jan Dietrick is helping me organize our ideas with the input from our friends into a series of articles on the following topics.    

Part 2: Defining how SPM actions relate to each other 

Part 3: Incentivize regenerative organic and ban disruptive chemical pesticides

Part 4: Biological control action levels–examples from the field

Part 5: Regional SPM focus with RCDs, field scouts, food hubs and insectaries

Part 6: New knowledge for pest prevention

Part 7: What has to be different for SPM? [Hint: life]

Part 8: Myths and truths about pest control

Part 9: SPM for city people


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