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The Status of Our Industry Regarding Varroa Mgmt and What Can We Do About It?




Contents

Introduction: A Reality Check on the American Beekeeping Industry’s Varroa Control Predicament 2

The Lead Up. 2

The Elephant in the Room.. 2

Our Conundrum.. 3

Our Predicament 3

A Personal Note. 4

Rationalization and Lack of Unreasonable Risk. 4

How the EPA Can Help Us 4

Our Current Arsenal: The Registered Varroacides 5

The Case for Approval of Extended-Release Oxalic Acid (OAE) 5

A Reality Check on Current Options for Mite Control with Natural Miticides 5

Fully Legal Option #1: Use Currently Registered Products 6

Fully Legal Option #2: Personal Use or Sale of Minimal-Risk Pesticides 6

Question #1: “Can I Use Less-Expensive Wood Bleach or Off-the-Shelf Oxalic Acid?” 7

Question #2: “Can I Up the Dose by Using Repeated Oxalic Applications?” 7

Question #3: “Can I Qualify for Experimental Use of Oxalic Acid?”. 7

Question #4: “What if I Say That I’m Using These Treatments for Something Else?”. 7

Question #5: “Can I Feed Aromatic Food Ingredients to Balance my Colony’s Ethereal Energy?”. 8

Question #6: “Am I Going to Get Busted if I Treat my Hives with Generic Oxalic Acid (wood bleach) by the Extended-Release Method?” 8

Coming Next Month. 9

Citations and Notes 9

 

 

The Status of Our Industry Regarding Varroa Management

and

What can we do about it?

Part 1

Randy Oliver

ScientificBeekeeping.com

First published in ABJ July 2023

 

Introduction: A Reality Check on the American Beekeeping Industry’s Varroa Control Predicament

The introduction of the parasitic varroa mite completely changed our industry, leading to a huge increase in rental rates for almond pollination, and a shift for most commercial beekeepers from managing for honey production to focusing upon having enough strong hives in February to fill pollination contracts. Our commercial industry was only saved by its unapproved uses of agricultural miticides. But commercial beekeepers have long known that that would only be a temporary fix. Evolution is catching up with us as varroa evolves resistance to the mainstay of our industry. The times they are a-changin’, and beekeepers are asking, “What are we gonna do?” One problem is that it’s not up to just us to figure out ― we gotta work it out with the EPA.

The Lead Up

The introduction or evolution of a pest, parasite, or pathogen can wreak havoc in agriculture, and the varroa mite did just that for the beekeeping industry. As researchers and beekeepers worldwide desperately scrambled to find efficacious and affordable mite treatments, the frustratingly-slow lag time between discovery and getting a formulated product through EPA’s registration process sometimes left us in the lurch. This occurred first with fluvalinate, granted a Section 18 emergency registration in 1987 to use the neurotoxic miticide for varroa detection by soaking it into wooden strips. Although EPA granted registration of Apistan strips (as a treatment) the following year, the cat was already out of the bag, and commercial beekeepers were soon making up their own inexpensive off-label fluvalinate treatments using the cattle dip Mavrik, which not only became an industry “standard,” but resulted in comb contamination and likely accelerated the evolution of resistant mites.

The situation didn’t improve when, after only about six years, mites started to exhibit resistance to fluvalinate. In response the neurotoxic organophosphate coumaphos got registered as Checkmite strips. Many beekeepers, accustomed to making up treatments at home, very unwisely and unsafely used a cattle dip powder with the same active ingredient (again leading to serious comb contamination).

And when the danged mite very rapidly developed resistance to coumaphos, beekeepers again faced a paucity of registered efficacious treatments, partially triggered by a lawsuit against Miticur (the first amitraz product labeled for honey bees), leading them to start making treatments using amitraz sourced from registered cattle dip products. Off-label use of amitraz soon again became the industry standard, indeed being the sole miticide used for the vast majority of beehives in the U.S. for the last twenty years, despite the registration of Apivar strips in 2013 (in exchange for the concurrent withdrawal of Taktic in 2014). Surprisingly, it’s taken an unexpectedly long time for varroa to show signs of resistance to amitraz.

The Elephant in the Room

Amitraz isn’t the most innocuous thing to be putting into our bee hives. It not only causes adverse effects upon the colony, but also endocrine disruption, neuro-, immuno-, reproductive, and developmental toxicity in mammals such as ourselves [[1]]. EPA was concerned about the total “risk cup” of human exposure to amitraz, and required the registrant to remove its use as a cattle dip in the U.S. in order to register it for use in beehives.

Appallingly, our honey and combs are now contaminated with its degradation products. The elephant in the room is the fact that since 2014 our commercial beekeeping industry has been almost entirely dependent upon the use of amitraz products illegally imported into the U.S.

EPA is aware of this, and issues Stop Sale, Use, or Removal Orders to advertisers on sites such as eBay and Amazon, and has recently taken action (involving fines and prison terms) against some smugglers. Yet, despite the FIFRA Enforcement Response Policy allowing for the issuance of Notices of Warning and penalties of $500 for a first offense, to date there has been little enforcement action taken on the illegal use of pesticides by beekeepers [[2]].

But this may be about to change. The State FIFRA Issues Research and Evaluation Group (SFIREG) has told the EPA, “Working to control and regulate pesticide misuse in the pollinator industry is very urgent” [[3]], and has formally requested “EPA to organize and respond to this important issue topic and to work quickly with SLAs to stop pesticide misuse [by beekeepers].”

The irony of this is that while beekeepers loudly complain about pesticides improperly applied by farmers, they themselves not only are the main source of pesticide exposure to their colonies, but often act as “pesticide scofflaws” themselves ― an irony not lost on the EPA.

But don’t get me wrong — in my opinion, the EPA has been unreasonably restrictive in registering products for us to use for varroa control. An important point not adequately taken into concern by the EPA is that, as opposed to the slaughter of millions of harmless insects, other invertebrates, birds, and aquatic species when farmers treat vast acreages with insecticides, the miticides that beekeepers apply within their hives have virtually no impact on the environment outside those hives. So it’s a valid question as to whether the same rules should apply to miticides that we use for varroa control (other than regulation to minimize any harmful contamination of honey).

A huge frustration to beekeepers is that research has demonstrated that the safe and eco-friendly extended-release application method of oxalic acid could greatly reduce our industry’s dependence upon amitraz, but there’s little sign that an inexpensive and registered formulated product will soon be on the market, leading many beekeepers to make up their own treatments using generic wood bleach (being openly sold by beekeeping supply houses). A few states tried to solve the problem by filing for Section 2(ee) exemptions for extended-release oxalic acid, but those exemptions were predictably rejected by the EPA. Beekeepers are now upset that they lost what they hoped would be a solution to “our varroa problem.”

Our Conundrum

As varroa begins to exhibit resistance to amitraz, our industry is now going into crisis mode, since there are an inadequate number of registered alternative efficacious varroacides on the market to fulfill the widely-varying needs of both recreational and commercial beekeepers ― notably when honey is being produced. Their current label restrictions require excessive time and labor, are physically demanding, and involve unnecessary risk to the applicators when applied to large numbers of colonies during hot weather.

Beekeepers would prefer to be able to control varroa with cost-effective approved miticides. Ideally, we would avoid the synthetic miticides (which contaminate our beeswax and honey with residues), and instead use the more consumer-friendly “natural” treatments. But since there is such a small margin of profit in beekeeping, the often high cost and narrow label application restrictions of registered miticides tempt beekeepers to mix up their own off-the-shelf treatments.

Our Predicament

  • Since beekeepers are such a minor industry, there is little financial incentive for Registrants to update their labels, or for companies to develop and register new or improved formulated products for varroa control.
  • Beekeepers are partly to blame for this, since we’ve shown the pesticide companies that it may not be worth their effort to reformulate or re-label an already-registered agricultural miticide into an expensive product for application to beehives, when they know that beekeepers will likely just prepare their own treatments from the less-expensive agricultural product, or use off-the-shelf chemicals already on the market.
  • So to our dismay, there appear to be few novel varroa control products in the registration pipeline.
  • The commercial beekeepers who manage the vast majority of colonies thus feel forced to use active ingredients out of compliance with the law.
  • Our state lead agencies and bee inspectors are stuck in the conundrum of knowing that our entire industry is dependent upon such unapproved applications, yet do not want to take enforcement action if the beekeepers have no good alternatives. This puts them in a difficult place.
  • Thus beekeepers are highly tempted to use readily available off-the-shelf natural treatments (formic, oxalic, thymol and other plant oils) that present no unreasonable risk to man or the environment and would be of little concern to inspectors, but due to EPA’s stringent requirement to rigidly follow their FIFRA mandate, are not legally allowed.

A Personal Note

As an independent honey bee researcher, supported financially by donations from beekeepers themselves, much of my research (under Pesticide Research Authorizations) involves the development and improvement of “natural” treatments for varroa control. Since I am also a professional beekeeper who successfully shifted from synthetic miticides to natural treatments over twenty years ago (using only oxalic, formic, and thymol in rotation), I’ve been frustrated by some of the shortcomings of the currently-registered treatments and their label restrictions, and publish my research findings on alternative application methods (sometimes collaborating with their Registrants).

But it takes an excruciatingly long time (and sometimes a lot of money) for a Registrant to get a revised application method, or a new formulated product, through the EPA registration process. This frustrating situation precipitated my writing of this “white paper“ as an objective, reality-based status report and assessment of the current predicament that our industry and its regulatory agencies are involved in, the various options that we beekeepers have at our disposal (or are currently using), and potential action items that our industry can take (initially with regard to registration of the extended-release method for application of oxalic acid, but then expanded to see how we might increase the overall availability of additional “natural” treatments for the control of varroa).

Rationalization and Lack of Unreasonable Risk

What our regulators should keep in mind is that people only respect laws that they feel are reasonable. Unreasonable laws tend to be ignored and not enforced.

Humans can rationalize most any behavior, and when a law seems unreasonable, it’s very easy to rationalize “breaking it.” We now have an entire industry that has rationalized using unapproved methods to control varroa.

FIFRA’s mandate is that the application of any pesticide should result in “no unreasonable risk to man or the environment.” It’s obvious to any beekeeper that using oxalic acid, formic acid, or thymol in their hive would in no way create either of those risks. Our regulators need to understand that for us to respect them, EPA’s regulations must make “common sense.”

The EPA’s strict adherence to the letter of the law regarding FIFRA, and to protect themselves from liability or lawsuits, may put them at odds with common sense and beekeeper practical experience. The active ingredients of the organic acids oxalic or formic, or the plant extract thymol, due to their rapid biodegradation, when applied to beehives pose absolutely no unreasonable risk to the environment, and since they all have tolerance exemptions in honey, no risk to the consumer, and with reasonable precaution, no more risk to the applicator than do commonly-used oven or toilet cleaners, bleaches, swimming pool treatments, etc. (Feel free to use this paragraph if you speak to your legislators).

How the EPA Can Help Us

As it is, the beekeeping industry is crying out for help. We simply do not have an adequate number of legal and practical options available to control the mite (notably during the honey flow), especially for the commercial operations that manage the vast majority of honey bee colonies and provide pollination services to the agricultural sector.

Our current situation opens a window of opportunity for the EPA or our legislators to step in to help the beekeeping industry shift from dependence upon a single synthetic miticide, to a range of natural treatments (to better allow us to practice integrated pest management, and to avoid the development of pesticide resistance). It also offers EPA the opportunity to help bring the beekeeping industry into compliance.

I fully support the EPA in its mandate to ensure that the miticides that we are allowed to use present no unreasonable risk to man or the environment, and do not wish for my research findings to encourage unapproved use. That said, potential registrants with whom I’ve consulted find that the procedures and requirements of the EPA make it frustratingly difficult and expensive, not to mention the years of effort involved in the process, to bring to market a registered varroa control product.

Our Current Arsenal: The Registered Varroacides

There are currently only a few registered varroacides on the market (Checkmite + and Sucrocide appear to be unavailable) ― only three of which are approved for application while colonies are producing honey (Table 1) [[4]].

Table 1. Currently-registered varroacides (“natural” pesticides highlighted in green)
Formulated

Product

Synthetic or

“natural”

Active Ingredient(s) Demonstrated

resistance?

Comb

contamination?

Can be used during honey flow?
Apistan Strips synthetic Fluvalinate Yes Yes No
Checkmite+ synthetic Coumaphos Yes Yes Yes
Apivar Strips synthetic Amitraz Yes Yes No
Amiflex synthetic Amitraz Yes Yes No
Api Life Var “natural” Thymol, eucalyptus, menthol No Slight No
Apiguard “natural” Thymol No Slight No
MAQS, Formic Pro “natural” Formic acid No No Yes
Hopguard III “natural” Hop beta acids No No Yes
Api-Bioxal “natural” Oxalic acid No No Yes

 

The three registered xenobiotic synthetic chemicals are not only of concern to consumers who consider honey to be a “natural” product, but their persistent nature has caused serious contamination of beeswax and honey, and due to the evolution of pesticide resistance are all now considered to be ineffective or unreliable. Thus our industry is greatly concerned as to how we are going to manage this destructive parasite, and is showing greater interest in the natural treatments, which although trickier to use, have fewer issues with comb or honey contamination.

The registered natural varroacides highlighted in green above, although great products, have label restrictions that limit their utility, or present unreasonable risks, to many of the diverse range of beekeeping operations.

The Case for Approval of Extended-Release Oxalic Acid (OAE)

There is an application method of oxalic acid that is registered by Aluen CAP in a number of countries, but not yet in the U.S. This application method is highly efficacious when brood is present in the hive, can be used during honey production, eliminates the need to remove and restack honey supers (since it can be applied before they are added), and presents less exposure risk to the applicator than the currently-approved application methods. For more details, please refer to Supplemental Information for OAE [[5]].

A Reality Check on Current Options for Mite Control with Natural Miticides

I initially wrote this document for the benefit of our industry leaders, to be used to inform our regulators and legislators. I am by no means a lawyer, but have interpreted Title 7 and FIFRA as best I can (with some guidance from those with experience in various agencies). Allow me to objectively present the current legal options available individual to beekeepers, as well as answers to some questions that beekeepers have asked me about.

Fully Legal Option #1: Use Currently Registered Products

This is the legal default ― to use only registered products per the label instructions. The recent registration of Amiflex paste takes away the excuse by commercial beekeepers that Apivar strips don’t work fast enough. We now have every reason to expect our state lead agencies to start cracking down on the illegal importation and use of amitraz cattle dips. Until there is inforcement action taken against beekeepers who use inexpensive smuggled amitraz, it creates an unlevel playing field conferring an unfair economic advantage to those who use unregistered products.

For most recreational beekeepers this is doable, as evidenced by my success in our own operation. But it may not be realistic for larger commercial operations, or for beekeepers with short seasons, or other issues.

The problem with the wait: Registrants are reluctant to go through the process of getting changes approved for their labels. Some have asked Chemicals Laif (the registrant of Api-Bioxal) to submit a change in label request to EPA to add the extended-release application method, or to allow a state to apply for a Section 24(c) Special Local Need Registration. The company does not appear to be interested. The reality is that even if it (or another company) eventually gets a label change or formulated product (such as Aluen CAP) approved, beekeepers across the country will already be using this method (using generic oxalic acid), and may be resistant to purchase a far more expensive registered product. Thus there is little incentive for companies to invest in new registrations.

Fully Legal Option #2: Personal Use or Sale of Minimal-Risk Pesticides

EPA offers individuals and companies the option of using pesticides on the Minimal Risk list without need for registration: “Generally, we do not review products that claim to meet the criteria set by 40 CFR 152.25(f) for exemption from pesticide regulation for companies planning to market such a product. We also do not provide a label review of such products. The producer is responsible to carefully read the criteria and make an evaluation of how the product meets (or does not meet) the criteria.” [[6]]

It is up to beekeepers, researchers, and private companies to develop some Minimal Risk ingredients into efficacious and safe varroa treatments.

This option would not immediately solve the urgent during-the-honey-flow problem, but allows beekeepers, researchers, and companies to experiment with and perhaps quickly develop new minimum-risk application methods or formulated products for varroa control.

Exempted products. Products containing the following active ingredients, alone or in combination with some other substances or inerts, are exempt from the requirements of FIFRA provided that all of the criteria of Section 40 CFR 152.25(f) are met. Refer to [[7]].

Minimum-risk Pesticides with potential for varroa control
Thyme oil Citronella oil
Clove oil (eugenol) Geranium oil
Peppermint oil Rosemary oil
Lemongrass oil Cedarwood oil
Cinnamon oil Citric acid

 

All the above oils are readily available and not too expensive. Unfortunately, most of them also exhibit adverse effects on the bees at dosages (typically ~10 mL) adequate to kill varroa [[8]]. One can find plenty of studies on Google Scholar, and some appear to show promise. Our industry should request the USDA and funding agencies to support further research into this list of products for varroa control!

Question #1: “Can I Use Less-Expensive Wood Bleach or Off-the-Shelf Oxalic Acid?”

The only oxalic acid source currently approved for varroa control is that registered and sold by Api-Bioxal, which unfortunately is priced far more expensively than off-the-shelf 99.6% pure oxalic acid. Beekeepers may do dumb things, but they ain’t stupid. To save money, some purchase a bag of expensive Api-Bioxol to keep on hand in case an inspector asks, and then treat their colonies with generic oxalic acid. This is not in any way legal. I’m in no position to guess how likely you are to get busted.

Question #2: “Can I Up the Dose by Using Repeated Oxalic Applications?”

The label for Api-Bioxal states: “Consult state guidelines and local extension experts about best application practices when applying Oxalic Acid Dihydrate when capped brood is present because multiple treatments several days apart will be needed to reduce successive cohorts of adult mites.” But those entities are not allowed to suggest any deviation to the application directions on the label!

There are problems with repeated dribble application, due not only to the labor involved in removing and replacing the honey supers above the brood chambers, but also the known adverse effects that repeated dribbles have upon the colony. This leaves the vaporization method as the only summer option. But vaporization (OAV) with the approved 1-gram dose per brood chamber exhibits very poor efficacy when brood is present, and requires 7-10 applications [[9]]. Recent research has shown that it takes about 3x the approved dosage to attain good efficacy [[10]].

Legality: Since there are no label restrictions for re-application intervals for oxalic vapor, to obtain efficacy when their colonies contain brood, some beekeepers are simply repeating applications every few days (or even during the same day to legally apply a larger dose). Technically, this would be legal. But using off-the-shelf wood bleach instead of Api-Bioxal would be illegal.

Question #3: “Can I Qualify for Experimental Use of Oxalic Acid?”

Until recently, the application of oxalic acid to beehives for pesticidal use remained illegal in California. So to do my research, I obtain a Pesticide Research Authorization from my state lead agency (SLA) each year. But in some states, their SLA defers to the EPA as far as experimental use of pesticides.

The EPA has informed me in writing that the Agency does not require — at the federal level — a beekeeper to obtain an Experimental Use Permit for experimental use of oxalic acid on their own hives (the use must be for experimental purposes only). However, your state may have more stringent requirements. You’d need to check with your state lead agency. It’s not clear to me whether experimental use would apply to generic oxalic acid, or only the use of Api-Bioxal. The beekeeper could not sell any honey produced during the experiments.

Question #4: “What if I Say that I’m Using These Treatments for Something Else?”

When laws appear to be unreasonable, some people skirt the intent of the statute by making disingenuous claims or performing quasi-legal workarounds. I by no means suggest that beekeepers engage in such quasi-legal workarounds, but some beekeepers who feel that they just can’t wait for EPA to approve new application methods for thymol or oxalic acid are covering their backsides by citing Title 40.I.E.152.8, Products that are not pesticides because they are not for use against pests [[11]].

Since Section (b) states that “A product intended to force bees from hives for the collection of honey crops is exempted,” some beekeepers are making the disingenuous claim that they are using thymol as a bee repellent. But if their thought bubble includes killing varroa, they’d be breaking the law.

Others cite Section (b): “The following types of products or articles are not considered to be pesticides unless a pesticidal claim is made on their labeling or in connection with their sale and distribution: (a) Deodorizers, bleaches, and cleaning agents.”

I’ve heard plenty of beekeepers claim that they are “bleaching their top bars,” using oxalic acid dissolved in glycerin as a wood bleach — leaving the pads in the hive between scrubbings. So long as their intent is solely for bleaching, and not for pesticidal use, this practice is technically legal. Again, if your thought bubble contains the word varroa, you’d be breaking the law.

Such clearly-intended workarounds place our state enforcement agents in a tough situation, since they can either wink and turn a blind eye, or pursue a difficult-to-win prosecution (from what I hear, most inspectors are not concerned about either of these ingredients, and are accustomed to seeing various pads in beehives).

Question #5: “Can I Feed Aromatic Food Ingredients to Balance my Colony’s Ethereal Energy?”

The EPA regulates pesticides; the FDA regulates the ingredients allowed to be used in animal feeds for sale. No agency cares much about what food products (or over-the-counter supplements) you feed to your own pets or livestock. Beekeepers are well known for feeding all sorts of things to their colonies to “improve colony health,” and this gets us into a murky area of the law, so long as the feeding is done without the intent of it functioning as a pesticide.

Not surprisingly, any number of plant products that may be found in your kitchen (and that you might even feed to your kids), when introduced into beehives may also inadvertently kill some mites, which would indeed likely improve colony health. Some that come to mind are anise, basil, cinnamon, coconut oil, fennel, garlic, geranium, lemon juice, mustard condiment, oregano, powdered sugar, turmeric, and wintergreen (and this is hardly a complete list). It would technically be illegal to use (or sell) them as varroa control agents, since that would be a pesticidal use, but similar to Honey B Healthy (which contains active ingredients known to exhibit varroacidal properties), it would be legal to feed any of the above food products to one’s colony with the sole intent of “improving colony health,” “stimulating buildup,” or “balancing their ethereal energy.” We clearly need more research on the effects of feeding such food products to our colonies!

Question #6: “Am I Going to Get Busted if I Treat my Hives with Generic Oxalic Acid (Wood Bleach) by the Extended-Release Method?”

Disclaimer: Randy Oliver does not encourage or condone any off-label use of any pesticide.

The sad fact is that beekeepers have unfortunately become accustomed to applying off-label treatments to their hives. Apiary inspectors, understanding our predicament, have long been turning a blind eye toward off-label varroa treatments (although a number are asking EPA for a crackdown on illegal use of smuggled amitraz).

We beekeepers are in the unfortunate situation that the only registered source of oxalic acid costs up to 50 times as much per gram as does readily-available 99.6% pure generic product. And the registered product’s label does not allow for application of it by the extended-release method. One can understand why beekeepers are tempted to skirt the law.

Desperate for an efficacious mite treatment that can be used during the honey flow, beekeepers nationwide are already making up their own extended-release oxalic acid pads (using generic oxalic acid), and will likely continue to do so even if an inexpensive formulated product comes to market. That said, they do face possible enforcement action (most likely a warning) for unauthorized use of generic oxalic acid as a pesticide.

Reality check: It takes no stretch of the imagination to expect that this application method of generic oxalic acid will likely become a “standard” for our industry. This is a bummer, since we would still be pesticide scofflaws, even though it’s obvious that putting some wood bleach into our hives poses “no unreasonable risk to man or the environment.”

Coming Next Month

Our industry leaders have been weighing options for proposed actions that we might take to help with “our varroa problem” and get us into compliance with the law. But similar to the 2(ee) exemptions for OAE requested by a number of states [[12]], we should do our homework before wasting our time (it was obvious that there was no way that the EPA could grant that exemption, since it included an increase in the dosage).

So I took it upon myself to do the homework for our leaders, going over the pros and cons of the various action items proposed for our industry to petition our regulators and legislators for. I’ve been in contact with some leaders as well as our industry lobbyist (and am already sharing information with them). I feel that all of us beekeepers should be fully informed (so that we can express our opinions to our representatives), so will lay out a summary of my assessment of the options for you next month.

Citations and Notes

[1] Del Pino, J, et al (2015). Molecular mechanisms of amitraz mammalian toxicity: a comprehensive review of existing data. Chemical research in toxicology 28(6): 1073-1094.

[2] The Adees did get fined in 2007 for applying fluvalinate and oxalic acid on blue shop towels.

[3] https://aapco.org/wp-content/uploads/2021/08/SFIREG-Letter-to-EPA-for-Managed-Pollinator-Issue-Paper-August-4-2021.pdf

[4] https://www.epa.gov/pollinator-protection/epa-registered-pesticide-products-approved-use-against-varroa-mites-bee-hives

[5] https://scientificbeekeeping.com/scibeeimages/Supplemental-Information-for-OAE.pdf

[6] https://www.epa.gov/minimum-risk-pesticides/minimum-risk-pesticide-definition-and-product-confirmation

[7] https://www.cdpr.ca.gov/docs/registration/sec25/minimum_risk_flowchart.pdf

[8] Imdorf, A, et al (1999) Use of essential oils for the control of Varroa jacobsoni Oud. in honey bee colonies. Apidologie 30(2-3): 209-228.

[9] Oliver, Randy, data sets in prep.

[10] Jack, C. J., van Santen, E., & Ellis, J. D. (2020) Evaluating the efficacy of oxalic acid vaporization and brood interruption in controlling the honey bee pest Varroa destructor (Acari: Varroidae). Journal of economic entomology, 113(2), 582-588.

[11] [66 FR 64763, Dec. 14, 2001, as amended at 73 FR 75594, Dec. 12, 2008]

  • 152.8 Products that are not pesticides because they are not for use against pests.

A substance or article is not a pesticide, because it is not intended for use against “pests” as defined in § 152.5, if it is:

(a) A fertilizer product not containing a pesticide.

(b) A product intended to force bees from hives for the collection of honey crops.

 

[53 FR 15975, May 4, 1988, as amended at 66 FR 64764, Dec. 14, 2001]

  • 152.10 Products that are not pesticides because they are not intended for a pesticidal purpose.

A product that is not intended to prevent, destroy, repel, or mitigate a pest, or to defoliate, desiccate or regulate the growth of plants, is not considered to be a pesticide. The following types of products or articles are not considered to be pesticides unless a pesticidal claim is made on their labeling or in connection with their sale and distribution:

(a) Deodorizers, bleaches, and cleaning agents;

[12] https://agriculture.vermont.gov/sites/agriculture/files/Oxalic%202ee.pdf

 

Category: Varroa Management