- Organic pesticides
- Use pest-specific pesticides
- List of organic pesticides
- See also
- External links
- Getting Straight on Glyphosate
- Organic Basics
- Spray What, Now?
- The Approved-Materials List
- The Organic Difference
- The Role of Biodiversity
- List of Organic Pesticides
- Bacillus Thuringiensis
- Beauveria Bassiana
- Kaolin Clay
- Neem Oil
- Plant Oils
- Types of Pesticides
- What Are Organic Pesticides And Are Organic Pesticides Safe To Use
- What are Organic Pesticides?
- Types of Natural Pesticides
- Homemade Organic Pesticides
- Gardening How-to Articles
- Natural Pesticides
- Microbial Pesticides
- Horticultural Oils
- Insecticidal Soaps
- Botanical Insecticides
- 5 Natural Pesticides You Could Use To Grow Your Own Kitchen Garden
- Organic pesticides not always ‘greener’ choice, study finds
- All Pesticides Are Toxic
- Integrated Pest Management (IPM)
- Requirements or Mandates
- If you think organic pest management might be the right approach for you, contact Modern Pest Services for more information, to get a quote or schedule your service. Our highly trained professionals are ready to discuss how our organic, low-impact, environmentally conscious methods can meet your pest management needs.
- Most recent
Organic pesticides are pesticides made from naturally occurring substances or self-made mixtures made from organic soaps and/or ethanol.
Organic pesticides can allow farmers to control pest and diseases in plants without resorting to conventional pesticides. This does not necessarily mean that they are safer to use. Organic presticides can be as damaging to the fauna/flora in the environment as chemical pesticides . However, in comparison to chemical pesticides, they can be much more easily decomposed by the environment.
This page lists the organic pesticides you can make locally, and discusses against which pest/disease it is effective. The recipes themselves can be found at organic pesticide recipes.
Use pest-specific pesticides
The key to using pesticides appropriately is to use pesticides that are (as much as possible) is to know exactly what the problem or pest/disease is that is causing problems. Some problems may not be pests/diseases at all, rather nutrient deficiencies. If it is a pest/disease, try to identify it before using any pesticides at all.
Here are some resources that can help you identify the problem:
- Texas Plant disease Handbook- This excellent resource has a list of common crops in Texas and commonly associated pests and diseases. Pictures included
- A guide to Natural Enemies in North America – List of predators with pictures. Useful guide but some latin may be required!!
- Household and Structural Pest Identification – Follow the key to identify common pests.
List of organic pesticides
Note: Where a plant is named as a potential pesticide, this plant the substance is derived from can often be intercropped to have the same pesticidal effect
|Organic Pesticide||Against which pests & diseases ?||Notes and academic articles|
|Baking soda, sodium bicarbonate||fungi, powdery mildew, rose black spot, anthracnose, downy mildew, brown patch||http://attra.ncat.org/attra-pub/bakingsoda.html|
|Black Jack seeds||Aphids, caterpillars||?|
|Bordeaux mixture||Aphids, caterpillars||Bordeaux mixture is a mixture of copper sulphate and slaked lime. It works preventively to fungal attacks. It is a very old mixture. The copper ions on the leaf prevent the germination of the fungal spores and the calcium also increases the pH.|
|Chinaberry leaves||Aphids, caterpillars||?|
|Cornmeal, cornmeal solutions||yellow leaves on photinia, brown patch, algae in seedlings, leaf spots on roses||?|
|copper sulphate /copper hydroxide /copper oxide||?||?|
|Dead bug spray||Any insects||http://wiwi.essortment.com/homemadeorgani_renu.htm|
|Garlic, garlic solutions, garlic oil||Aphids, thrips, mosquitoes, onion flies, rabbits (on potatoes), other chewing and sucking insects||When using garlic on soil with thrips, it will cause the thrips to come to the surface. Once they are at the surface, fermented water/plant mix (from stinging nettle) can be used. Garlic can also be intercropped to repel similar insects|
|Human/animal urine||Aphids, caterpillars||Has dual use as it acts both a fertiliser and a pesticide|
|Kaolin Clay||Protects mainly against insects, but also some diseases. May also reduce damage from birds since there are less insects to attract them.||Non toxic to humans, and not known to hamper activities of beneficial insects such as honey bees.|
|Milk, milk solutions||Mildew, blight||Abstract, Crop Science (Vol. 18, 1999, pp. 489-92)|
|Neem leaves, neem oil||Aphids, Bull worm, caterpillars||Neem can have multiple functions such as for medicinal use. See Neem article|
|Paprika, hot pepper||cats, dogs, insects, bugs, snails and snails (on leaves)||often used in combination with spearmint to improve effectiveness|
|Pyrethrum||?||this plant-based insecticide is a strong neurotoxin to all cold-blooded creatures. It is virtually harmless to warm-blooded creatures however. Pyrethrum breaks down within 48 hours. Other plant-based insecticides are Koppert Rotenon and Koppert Plantschoon.|
|Rock meal||bacteria, fungi, some insects||Seaweed calcium, basalt and lava meal increase the acidity which protects crops from bacteria/fungi. The fine rock meal has a dehydrating effect and damages the wax layer of many insects. By dusting or spraying, the plants are covered with a thin layer of dust. Treatment is done in the evening and it should not rain for 12 hours (maximally done for up to 2 times per month). Dosage= 250g/are.|
|Silicic acid||?||spraying of this increases the plant defenses|
|Soap, soapsuds, soap solutions||Slugs, aphids||Solutions can be sprayed on any plant leaves or used near affected plants|
|Spearmint||insects, bugs, chewing insects||often used in combination with hot pepper to improve effectiveness|
|Sulphur||several fungi (mildew and scab)||one sprays pure sulphur. It is harmless to humans and animals. Bio-S is a commercial sulphur product.|
|Tobacco, nicotine, nicotine solutions||Caterpillars, aphids, many types of worms, fungus gnats, symphylids, centipedes, root lice, other underground pests||Solutions can be sprayed on any plant leaves or used near affected plants|
|Tomato leaves||common insects, blight|
|(Wood) ash||Common insects||repellant substances as wood ash can be placed around the edge of vegetable areas to reduce pests. It is presumed that this materials is avoided by insects and small rodents
Herbal repellents from Soberbio Veto
|Soberbio Veto||Rat, Lizard, Roach, Snake||. This is formula with organic extracts of Margosa, eucalyptus, holy basil, clove oil etc do it yourself technique with convenience of just keep the extract in a area and with the diffusion in air it irritates and repels pest.|
- http://www.bna.com/webwatch/organicpesticide.htm Organic pesticides]
- Organic pesticide recipes
- Fertiliser – some fertilisers also work as a pesticide against some pests
- Chemical pesticides – persistent pesticides, only allowed in conventional farming
People believe a lot of things that we have little to no evidence for, like that vikings wore horned helmets or that you can see the Great Wall of China from space. One of the things I like to do on my blogs is bust commonly held myths that I think matter. For example, I get really annoyed when I hear someone say sharks don’t get cancer (I’ll save that rant for another day). From now onward, posts that attack conventionally believed untruths will fall under a series I’m going to call “Mythbusting 101.”
Ten years ago, Certified Organic didn’t exist in the United States. Yet in 2010, a mere eight years after USDA’s regulations officially went into effect, organic foods and beverages made $26.7 billion. In the past year or two, certified organic sales have jumped to about $52 billion worldwide despite the fact that organic foods cost up to three times as much as those produced by conventional methods. More and more, people are shelling out their hard-earned cash for what they believe are the best foods available. Imagine, people say: you can improve your nutrition while helping save the planet from the evils of conventional agriculture – a complete win-win. And who wouldn’t buy organic, when it just sounds so good?
Here’s the thing: there are a lot of myths out there about organic foods, and a lot of propaganda supporting methods that are rarely understood. It’s like your mother used to say: just because everyone is jumping off a bridge doesn’t mean you should do it, too. Now, before I get yelled at too much, let me state unequivocally that I’m not saying organic farming is bad – far from it. There are some definite upsides and benefits that come from many organic farming methods. For example, the efforts of organic farmers to move away from monocultures, where crops are farmed in single-species plots, are fantastic; crop rotations and mixed planting are much better for the soil and environment. My goal in this post isn’t to bash organic farms, instead, it’s to bust the worst of the myths that surround them so that everyone can judge organic farming based on facts. In particular, there are four myths thrown around like they’re real that just drive me crazy.
Myth #1: Organic Farms Don’t Use Pesticides
When the Soil Association, a major organic accreditation body in the UK, asked consumers why they buy organic food, 95% of them said their top reason was to avoid pesticides. They, like many people, believe that organic farming involves little to no pesticide use. I hate to burst the bubble, but that’s simply not true. Organic farming, just like other forms of agriculture, still uses pesticides and fungicides to prevent critters from destroying their crops. Confused?
So was I, when I first learned this from a guy I was dating. His family owns a farm in rural Ohio. He was grumbling about how everyone praised the local organic farms for being so environmentally-conscientious, even though they sprayed their crops with pesticides all the time while his family farm got no credit for being pesticide-free (they’re not organic because they use a non-organic herbicide once a year). I didn’t believe him at first, so I looked into it: turns out that there are over 20 chemicals commonly used in the growing and processing of organic crops that are approved by the US Organic Standards. And, shockingly, the actual volume usage of pesticides on organic farms is not recorded by the government. Why the government isn’t keeping watch on organic pesticide and fungicide use is a damn good question, especially considering that many organic pesticides that are also used by conventional farmers are used more intensively than synthetic ones due to their lower levels of effectiveness. According to the National Center for Food and Agricultural Policy, the top two organic fungicides, copper and sulfur, were used at a rate of 4 and 34 pounds per acre in 1971 1. In contrast, the synthetic fungicides only required a rate of 1.6 lbs per acre, less than half the amount of the organic alternatives.
The sad truth is, factory farming is factory farming, whether its organic or conventional. Many large organic farms use pesticides liberally. They’re organic by certification, but you’d never know it if you saw their farming practices. As Michael Pollan, best-selling book author and organic supporter, said in an interview with Organic Gardening,
“They’re organic by the letter, not organic in spirit… if most organic consumers went to those places, they would feel they were getting ripped off.”
What makes organic farming different, then? It’s not the use of pesticides, it’s the origin of the pesticides used. Organic pesticides are those that are derived from natural sources and processed lightly if at all before use. This is different than the current pesticides used by conventional agriculture, which are generally synthetic. It has been assumed for years that pesticides that occur naturally (in certain plants, for example) are somehow better for us and the environment than those that have been created by man. As more research is done into their toxicity, however, this simply isn’t true, either. Many natural pesticides have been found to be potential – or serious – health risks.2
Take the example of Rotenone. Rotenone was widely used in the US as an organic pesticide for decades 3. Because it is natural in origin, occurring in the roots and stems of a small number of subtropical plants, it was considered “safe” as well as “organic”. However, research has shown that rotenone is highly dangerous because it kills by attacking mitochondria, the energy powerhouses of all living cells. Research found that exposure to rotenone caused Parkinson’s Disease-like symptoms in rats 4, and had the potential to kill many species, including humans. Rotenone’s use as a pesticide has already been discontinued in the US as of 2005 due to health concerns***, but shockingly, it’s still poured into our waters every year by fisheries management officials as a piscicide to remove unwanted fish species.
The point I’m driving home here is that just because something is natural doesn’t make it non-toxic or safe. Many bacteria, fungi and plants produce poisons, toxins and chemicals that you definitely wouldn’t want sprayed on your food.
Just last year, nearly half of the pesticides that are currently approved for use by organic farmers in Europe failed to pass the European Union’s safety evaluation that is required by law 5. Among the chemicals failing the test was rotenone, as it had yet to be banned in Europe. Furthermore, just over 1% of organic foodstuffs produced in 2007 and tested by the European Food Safety Authority were found to contain pesticide levels above the legal maximum levels – and these are of pesticides that are not organic 6. Similarly, when Consumer Reports purchased a thousand pounds of tomatoes, peaches, green bell peppers, and apples in five cities and tested them for more than 300 synthetic pesticides, they found traces of them in 25% of the organically-labeled foods, but between all of the organic and non-organic foods tested, only one sample of each exceeded the federal limits8.
Not only are organic pesticides not safe, they might actually be worse than the ones used by the conventional agriculture industry. Canadian scientists pitted ‘reduced-risk’ organic and synthetic pesticides against each other in controlling a problematic pest, the soybean aphid. They found that not only were the synthetic pesticides more effective means of control, the organic pesticides were more ecologically damaging, including causing higher mortality in other, non-target species like the aphid’s predators9. Of course, some organic pesticides may fare better than these ones did in similar head-to-head tests, but studies like this one reveal that the assumption that natural is better for the environment could be very dangerous.
Even if the organic food you’re eating is from a farm which uses little to no pesticides at all, there is another problem: getting rid of pesticides doesn’t mean your food is free from harmful things. Between 1990 and 2001, over 10,000 people fell ill due to foods contaminated with pathogens like E. coli, and many have organic foods to blame. That’s because organic foods tend to have higher levels of potential pathogens. One study, for example, found E. coli in produce from almost 10% of organic farms samples, but only 2% of conventional ones10. The same study also found Salmonella only in samples from organic farms, though at a low prevalence rate. The reason for the higher pathogen prevalence is likely due to the use of manure instead of artificial fertilizers, as many pathogens are spread through fecal contamination. Conventional farms often use manure, too, but they use irradiation and a full array of non-organic anti-microbial agents as well, and without those, organic foods run a higher risk of containing something that will make a person sick.
In the end, it really depends on exactly what methods are used by crop producers. Both organic and conventional farms vary widely in this respect. Some conventional farms use no pesticides. Some organic farms spray their crops twice a month. Of course, some conventional farms spray just as frequently, if not more so, and some organic farms use no pesticides whatsoever. To really know what you’re in for, it’s best if you know your source, and a great way to do that is to buy locally. Talk to the person behind the crop stand, and actually ask them what their methods are if you want to be sure of what you’re eating.
Myth #2: Organic Foods are Healthier
Some people believe that by not using manufactured chemicals or genetically modified organisms, organic farming produces more nutritious food. However, science simply cannot find any evidence that organic foods are in any way healthier than non-organic ones – and scientists have been comparing the two for over 50 years.
Just recently, an independent research project in the UK systematically reviewed the 162 articles on organic versus non-organic crops published in peer-reviewed journals between 1958 and 2008 11. These contained a total of 3558 comparisons of content of nutrients and other substances in organically and conventionally produced foods. They found absolutely no evidence for any differences in content of over 15 different nutrients including vitamin C, ?-carotene, and calcium. There were some differences, though; conventional crops had higher nitrogen levels, while organic ones had higher phosphorus and acidity – none of which factor in much to nutritional quality. Further analysis of similar studies on livestock products like meat, dairy, and eggs also found few differences in nutritional content. Organic foods did, however, have higher levels of overall fats, particularly trans fats. So if anything, the organic livestock products were found to be worse for us (though, to be fair, barely).
“This is great news for consumers. It proves that the 98% of food we consume, which is produced by technologically advanced agriculture, is equally nutritious to the less than 2% derived from what is commonly referred to as the ‘organic’ market,” said Fredhelm Schmider, the Director General of the European Crop Protection Association said in a press release about the findings.12
Joseph D. Rosen, emeritus professor of food toxicology at Rutgers, puts it even more strongly. “Any consumers who buy organic food because they believe that it contains more healthful nutrients than conventional food are wasting their money,” he writes in a comprehensive review of organic nutritional claims13.
Strong organic proponents also argue that organic food tastes better. In the same poll where 95% of UK organic consumers said they buy organic to avoid pesticides, over two-thirds of respondents said organic produce and meats taste better than non-organic ones. But when researchers had people put their mouths to the test, they found that people couldn’t tell the difference between the two in blind taste tests14, 18.
So, in short, organics are not better for us and we can’t tell the difference between them and non-organic foods. There may be many things that are good about organic farming, from increased biodiversity on farms to movement away from monocultures, but producing foods that are healthier and tastier simply isn’t one of them.
Myth #3: Organic Farming Is Better For The Environment
As an ecologist by training, this myth bothers me the most of all three. People seem to believe they’re doing the world a favor by eating organic. The simple fact is that they’re not – at least the issue is not that cut and dry.
Yes, organic farming practices use less synthetic pesticides which have been found to be ecologically damaging. But factory organic farms use their own barrage of chemicals that are still ecologically damaging, and refuse to endorse technologies that might reduce or eliminate the use of these all together. Take, for example, organic farming’s adamant stance against genetically modified organisms (GMOs).
GMOs have the potential to up crop yields, increase nutritious value, and generally improve farming practices while reducing synthetic chemical use – which is exactly what organic farming seeks to do. As we speak, there are sweet potatoes are being engineered to be resistant to a virus that currently decimates the African harvest every year, which could feed millions in some of the poorest nations in the world15. Scientists have created carrots high in calcium to fight osteoperosis, and tomatoes high in antioxidants. Almost as important as what we can put into a plant is what we can take out; potatoes are being modified so that they do not produce high concentrations of toxic glycoalkaloids, and nuts are being engineered to lack the proteins which cause allergic reactions in most people. Perhaps even more amazingly, bananas are being engineered to produce vaccines against hepatitis B, allowing vaccination to occur where its otherwise too expensive or difficult to be administered. The benefits these plants could provide to human beings all over the planet are astronomical.
Yet organic proponents refuse to even give GMOs a chance, even to the point of hypocrisy. For example, organic farmers apply Bacillus thuringiensis (Bt) toxin (a small insecticidal protein from soil bacteria) unabashedly across their crops every year, as they have for decades. It’s one of the most widely used organic pesticides by organic farmers. Yet when genetic engineering is used to place the gene encoding the Bt toxin into a plant’s genome, the resulting GM plants are vilified by the very people willing to liberally spray the exact same toxin that the gene encodes for over the exact same species of plant. Ecologically, the GMO is a far better solution, as it reduces the amount of toxin being used and thus leeching into the surrounding landscape and waterways. Other GMOs have similar goals, like making food plants flood-tolerant so occasional flooding can replace herbicide use as a means of killing weeds. If the goal is protect the environment, why not incorporate the newest technologies which help us do so?
But the real reason organic farming isn’t more green than conventional is that while it might be better for local environments on the small scale, organic farms produce far less food per unit land than conventional ones. Organic farms produce around 80% that what the same size conventional farm produces16 (some studies place organic yields below 50% those of conventional farms!).
Right now, roughly 800 million people suffer from hunger and malnutrition, and about 16 million of those will die from it17. If we were to switch to entirely organic farming, the number of people suffering would jump by 1.3 billion, assuming we use the same amount of land that we’re using now. Unfortunately, what’s far more likely is that switches to organic farming will result in the creation of new farms via the destruction of currently untouched habitats, thus plowing over the little wild habitat left for many threatened and endangered species.
Already, we have cleared more than 35% of the Earth’s ice-free land surface for agriculture, an area 60 times larger than the combined area of all the world’s cities and suburbs. Since the last ice age, nothing has been more disruptive to the planet’s ecosystem and its inhabitants than agriculture. What will happen to what’s left of our planet’s wildlife habitats if we need to mow down another 20% or more of the world’s ice-free land to accommodate for organic methods?
The unfortunate truth is that until organic farming can rival the production output of conventional farming, its ecological cost due to the need for space is devastating. As bad as any of the pesticides and fertilizers polluting the world’s waterways from conventional agriculture are, it’s a far better ecological situation than destroying those key habitats altogether. That’s not to say that there’s no hope for organic farming; better technology could overcome the production gap, allowing organic methods to produce on par with conventional agriculture. If that does occur, then organic agriculture becomes a lot more ecologically sustainable. On the small scale, particularly in areas where food surpluses already occur, organic farming could be beneficial, but presuming it’s the end all be all of sustainable agriculture is a mistake.
Myth #4: It’s all or none
The point of this piece isn’t to vilify organic farming; it’s merely to point out that it’s not as black and white as it looks. Organic farming does have many potential upsides, and may indeed be the better way to go in the long run, but it really depends on technology and what we discover and learn in the future. Until organic farming can produce crops on par in terms of volume with conventional methods, it cannot be considered a viable option for the majority of the world. Nutritionally speaking, organic food is more like a brand name or luxury item. It’s great if you can afford the higher price and want to have it, but it’s not a panacea. You would improve your nutritional intake far more by eating a larger volume of fruits and vegetables than by eating organic ones instead of conventionally produced ones.
What bothers me most, however, is that both sides of the organic debate spend millions in press and advertising to attack each other instead of looking for a resolution. Organic supporters tend to vilify new technologies, while conventional supporters insist that chemicals and massive production monocultures are the only way to go. This simply strikes me as absurd. Synthetic doesn’t necessarily mean bad for the environment. Just look at technological advances in creating biodegradable products; sometimes, we can use our knowledge and intelligence to create things that are both useful, cheap (enough) and ecologically responsible, as crazy as that idea may sound.
I also firmly believe that increasing the chemicals used in agriculture to support insanely over-harvested monocultures will never lead to ecological improvement. In my mind, the ideal future will merge conventional and organic methods, using GMOs and/or other new technologies to reduce pesticide use while increasing the bioavailability of soils, crop yield, nutritional quality and biodiversity in agricultural lands. New technology isn’t the enemy of organic farming; it should be its strongest ally.
As far as I’m concerned, the biggest myth when it comes to organic farming is that you have to choose sides. Guess what? You don’t. You can appreciate the upsides of rotating crops and how GMOs might improve output and nutrition. You, the wise and intelligent consumer, don’t have to buy into either side’s propaganda and polarize to one end or another. You can, instead, be somewhere along the spectrum, and encourage both ends to listen up and work together to improve our global food resources and act sustainably.
See more on this, in response to critiques: In the immortal words of Tom Petty: “I won’t back down”
More Mythbusting 101:
Sharks will cure cancer
*** Oh, it turns out Rotenone got re-approved for organic use in 2010. See for yourself.
Regarding the use of GMOs: perhaps Andy Revkin from The New York Times says it better.
Based on the responses, I just want to make this clear: this is NOT a comprehensive comparison of organic and conventional agriculture, nor is it intended to be. That post would be miles long and far more complex. My overall belief is that there shouldn’t be a dichotomy in the first place – there are a variety of methods and practices that a farmer can use, each with its pros and cons. The main point here is that something “organic” isn’t intrinsically better than something that isn’t, and that you have to approach all kinds of agriculture critically to achieve optimum sustainability.
Ok, and while I’m adding in notes: stop citing Bedgley et al. 2007 as evidence that organic farming produces equal yields: this study has been shown to be flawed (see my comments in the follow up post to this article), and was strongly critiqued (e.g. this response article).
This blog post is part of a special series called “The Truth About Organic.” Want more? Download the full “The Truth About Organic” guide here.
Getting Straight on Glyphosate
Many families choose organic to avoid exposure to toxic chemicals. Enter glyphosate.
Glyphosate is the chief ingredient in the weed-killer RoundUp, one of the most commonly used herbicides worldwide. Glyphosate is so ubiquitous in our food, water, and air that it is regularly found in human urine.1
The toxicity of glyphosate is hotly debated. The EPA says glyphosate is safe2; the International Agency for Research on Cancer says glyphosate is a probable carcinogen3. Questions about Monsanto’s influence on studies proclaiming its safety abound.
RoundUp has been potentially linked to instances of cancer4, celiac disease5, Parkinsons6, and more. In two separate cases, a jury determined that the use of RoundUp contributed to occurrences of non-Hodgkins lymphoma.7
Dewayne Johnson, a groundskeeper who sued Monsanto/Bayer on charges that their Roundup product caused his non-Hodgkin’s lymphoma, was awarded $39 million in compensatory and $250 million in punitive damages. Source: Getty Images/New York Times
Glyphosate, which is patented as a broad-spectrum antibiotic, may damage beneficial bacteria in your microbiome. If you’d like to take a deeper dive into possible connections between glyphosate, GMOs, and gut health, we recommend this podcast.
Meanwhile, glyphosate and RoundUp applications have increased around the globe. Despite precision techniques, we’re using more herbicides than ever before8, and we’re sicker than we’ve ever been.
For consumers who aren’t okay with eating RoundUp, there’s organic.
A product with the USDA Certified Organic seal must be grown or produced with no synthetic herbicides, pesticides, or fertilizers—and that means no RoundUp and no glyphosate.
But organic is more than that. Organic not only bans synthetic herbicides like RoundUp—it prohibits the use of hundreds of chemical additives, preservatives, colorings, and more. See a full list of chemicals you’ll never have to eat if you buy organic here.
Spray What, Now?
When consumers find out that organic farmers do sometimes use sprays and other “inputs,” they’re understandably confused.
Do organic farmers spray? And why do some people say that organic sprays are even more toxic than conventional?
The key word is “synthetic.” Generally, organic farmers use no synthetic (read: man-made) inputs. However, they are allowed to use natural ones. But the story is more nuanced than that.
The Approved-Materials List
The National Organic Standards Board and the National Organic Program (read more about who they are and what they do here) maintain a list of materials approved for use in organic production.
The national list is determined with input from board members including farmers, business owners, and consumer advocates. The public—that’s you—is invited to submit opinions on what makes the list. Anyone can file a petition to have materials added or removed. Learn more about that process here.
Organic farmers are restricted in what materials they can use on their farms. Photo: DoDo Phanthamaly
Once the NOSB and NOP add a material to the national list, third-party organizations like the Organic Materials Review Institute (OMRI) evaluate new products to make sure they’re in compliance. It’s a process that involves hundreds of technical experts. Organic certifiers rely on OMRI to know which product a farmer or business can use and in what way (more on this later).
The general rule for the national list is that naturally occurring materials are allowed, and synthetic materials are prohibited. There are, however, exceptions to that rule.
Dr. Andrew Smith, our chief scientist, explains the basic distinction between approved and non-approved materials this way:
“Approved substances are naturally derived and quickly degrade by weather, or else they are easily broken down by microbes in the environment, lowering the chance of human exposure. Chemical pesticide formulations and other synthetic materials are manipulated in laboratories and persist for longer periods of time in the environment. They are foreign to the human body, which might see the compounds as intruders.”
So, how does the USDA, the NOSB, and the NOP go about determining which materials are allowed?
Synthetic vs. Non-synthetic
First, when considering a material for use in organic production, the USDA determines whether it is synthetic or non-synthetic. They define non-synthetic as “a substance that is derived from mineral, plant, or animal matter and does not undergo a synthetic process. Non-synthetic is used as a synonym for natural.”
Almost all natural materials are approved for use in organic. Take, for example, neem oil. Neem oil is derived from the seeds of the neem tree. It has been used for hundreds of years to minimize pests and plant diseases. Neem oil is natural and approved for use in organic.
Most synthetic materials are prohibited on organic farms.
Only a handful of natural substances are prohibited in organic production, including arsenic and tobacco dust.
Synthetic is defined as “a substance that is formulated or manufactured by a chemical process or by a process that chemically changes a substance extracted from naturally occurring plant, animal, or mineral sources.” Glyphosate, a laboratory-manufactured chemical, falls under this category and is thus prohibited.
Most synthetics are prohibited in organic—unless there is no naturally occurring alternative. Copper sulfate is one such synthetic. Copper can be dangerous if it accumulates in the body or the soil9, but it has been approved for use in organic for a few reasons:
- No natural alternative exists that can effectively target the same plant diseases as copper sulfate.
- Before approval, the USDA evaluated copper for its environmental impact, effects on human health, and more. Copper was determined safe with restrictions on its use (more on this below). Read about the review process here.
- Farmers can only use copper once they’ve exhausted all other options, including preventative management. It can only be applied in specific amounts and specific cases.
The national list of approved materials is divided into categories including crops, livestock, and processing. Each is further separated into “use class.” Examples of use class include “crop fertilizer” and “disease control,” among others. If a material is designated for fertilizer, it can’t be used in any other way.
Organic farmers can only use inputs after all other options have been exhausted. This photo shows mechanical trapping of insects, an organic method that avoids sprays.
Copper sulfate is designated for plant disease control and disease control only. Organic farmers can only spray copper if there is a documented case for its need. That means the farmer must also show that they have exhausted all other options for combating the disease issue. A certifier will review the documents and information and only approve copper’s use if there is nothing left to be done and a farmer’s crop is at risk.
Additionally, the certifier will work with the farmer to make sure only the minimum amount of the material is applied. Preference is always given to biological and preventative methods before a synthetic material is introduced, and exposure is always minimized as much as possible.
The Organic Difference
That’s a key difference between organic and conventional farming: Whereas conventional methods often encourage or recommend the use of chemical sprays to remedy problems as soon as they appear, organic philosophy encourages and requires a farmer take all other approaches first.
The idea in organic is always management before inputs. Take, for example, the organic approach to fighting pests. An organic farmer’s first line of defense is always prevention. Healthy soil creates strong plants that are naturally resilient to pest pressure.
Pollinators and natural predators help organic farmers reduce their need for sprays or other inputs.
For more persistent pest issues, farmers can encourage populations of natural predators and beneficial insects like ladybugs by planting wildflowers or pollinator habitat. Other strategies include crop rotation and selecting pest-resistant varieties of crops. When pests become a more serious problem, organic farmers might use natural pheromones to disturb pest mating cycles, or mechanical controls like trapping.
Only when all other methods have been exhausted and a farmer is faced with a potential significant loss will targeted sprays of organic-approved pesticides be used. Broad sprays of non-specific pesticides are always a last resort.
When it comes to fertilizers and plant nutrition, the same idea applies. Organic farmers start with the soil and use natural processes like composting to encourage fertility instead of chemical sprays. The idea is always to work with nature’s own processes first.
The Role of Biodiversity
As the organic industry booms, the kinds of farms growing organic products is changing. More and more large farms are joining the movement, and those large farms often grow just a single crop for efficiency.
Monoculture farms grow just one thing in large swaths, decreasing biodiversity. Photo: Johny Goerend
Complex ecosystems have more natural defenses than monoculture farms. A smaller farm that grows vegetables, raises some livestock, encourages pollinators, and creates habitat for wildlife will experience less pest pressure and disease than a large farm growing just one thing.
Large farms are more likely—though by no means guaranteed—to use more organic-approved sprays because fewer tools and defenses are available in the natural landscape. If you are concerned about avoiding even organic-approved sprays, do some research on the farms that grow the produce that you and your family enjoy.
What It All Means for You
The bottom line is this:
- Organic is a surefire way to avoid the most dangerous chemicals on the market, including glyphosate, which has been implicated in human health concerns.
- Organic-approved inputs are generally natural and safer than conventional.
- Organic-approved inputs go through a rigorous review to determine their safety and have many restrictions on their use. Materials are reviewed every few years, so the process is never stagnant.
- Organic farmers only use inputs as a last resort.
- If you’re especially concerned about exposure to sprays, even organic-approved sprays, it’s best to know and talk to your farmer.
- If you’re concerned about the safety of an approved material, speak up. The NOSB and NOP want to hear from you. Anyone can file a petition here.
- Organic is about more than pesticides and fertilizers. Organic also prohibits dozens of artificial preservatives and additives and enhances biodiversity and natural ecosystems. If you want to minimize your family’s exposure to harmful chemicals, organic is the obvious choice.
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List of Organic Pesticides
grasshopper image by pearlguy from Fotolia.com
Using organic materials for gardening or yard care is appealing to many home owners or gardeners because they are generally considered safe to use. This isn’t always the case. Some organic pesticides can harm both your body and the environment if not used properly. The U.S. Environmental Protection Agency recommends that you read and follow the instructions and warnings on the label to ensure safe and proper usage.
Bacillus thuringiensis, more commonly referred to as Bt, is a biological pesticide, which means it is a living organism that is in some way lethal to garden or yard pests. Bt is ingested by insects and produces a protein that is toxic to some insects. Different strains of Bt are used to control different types of insects, including moths, beetles, flies and mosquitoes. Researchers at the Aroian Lab on the campus of the University of California, San Diego report that Bt was first used as a pesticide in the 1920s.
Another biological pesticide, Beauveria bassiana, is a fungus that infects aphids, caterpillars, grasshoppers, ants and other insects and multiplies until it kills its host. The organic farming book, “Resource Guide for Organic Insect and Disease Management,” reports that this fungus occurs naturally in some soils but is cultivated specifically as an organic pesticide.
Kaolin clay is a type of clay that, according to the U.S.EPA, was approved as an organic pesticide in 1998. It is used on various types of produce to protect against mites, insects, fungi, and harmful bacteria. It is sprayed on plants or trees in a powdered form to act as a physical barrier between pests and the plants.
Neem oil is a brown oil with an unpleasant taste and smell that acts as a repellent for insects and is non-toxic to humans and beneficial insects such as honey bees. The U.S. EPA reports that neem oil is pressed from the seeds of the neem tree, which is native to India.
Although pyrethrum is a natural botanical pesticide that comes from dried flowers, not all forms of this pesticide are approved for organic use because of the levels of toxicity it can contain, states the “Resource Guide for Organic Insect and Disease Management.” Mixtures of pyrethrum that have been approved for use in organic farming will be labeled as such.
There are several different types of plant oils that are used as organic pesticides. The U.S. EPA lists orange oil, canola oil, mustard oil, castor oil and soybean oil among them. They are used to either kill or repel insects and are also used to repel larger pests, such as cats, dogs or deer. Of all the plant oils approved for use as organic pesticides, only wintergreen oil is noted for having a toxic effect on humans in high doses.
While much about modern farming techniques center around the use of synthetic pesticides (a catch-all term that includes herbicides, insecticides, and fungicides) on large acreage, organic producers of all sizes also use a variety of chemicals to control weeds and bugs on their farms. This article contains a list of organic pesticides approved by the United States Department of Agriculture for use on non-conventional farms.
The selections about which substances are allowed under the USDA’s National Organic Program are made by a board that includes organic growers, handlers, retailers, environmentalists, scientists, USDA-accredited certifying agents, and consumer advocates. Contrary to popular belief, pesticides approved for use on organic farms do include some synthetic substances, though the vast majority are natural toxins. That said, it should be clear that not all natural toxins are permitted — for example, strychnine and arsenic are natural but not allowed to be used in organic farming.
Of course, genetic engineering is not allowed in organic production. To meet the USDA organic regulations, farmers and processors must show they aren’t using GMOs (in this case, meaning high-tech modern plant breeding techniques) and that they are protecting their products from contact with prohibited substances from farm to table.
Just because a pesticide product is natural doesn’t mean it is less toxic than it’s synthetic counterpart. The dose, frequency of application, and mode of action all contribute to toxicity, and the severity is determined by the United States Environmental Protection Agency.
Below are many of the substances, both synthetic and non-synthetics, used in organic farming (this list includes the rule update that was finalized in January 2019). A full list of allowed synthetic substances and prohibited natural substances can be found here.
List of major substances
Boric acid: Structural pest control, no direct contact with organic food or crops.
Copper: Copper hydroxide, copper oxide, copper oxychloride, includes products exempted from EPA tolerance, provided that copper-based materials must be used in a manner that minimizes accumulation in the soil and shall not be used as herbicides.
Copper sulfate: Application rates are limited to levels which do not increase baseline soil test values for copper over a timeframe agreed upon by the producer and accredited certifying agent.
Cydia pomonella granulosis
Lime sulfer: Including calcium polysulfide
Minerals such as elemental sulfur, bicarbonate, or kaolin clay
Non-detergent insecticidal soaps: As a pesticide, fungicide, or algaecide for food crops
Oils, including petroleum, vegetable, and fish oils: Types include dormant, suffocating, and summer oils
Peracetic acid: For use to control fire blight bacteria. Also permitted in hydrogen peroxide formulations at a concentration of no more than 6% as indicated on the pesticide product label
Pheromones and pheromone traps
Plant-derived substances such as neem, caraway oil, seed fennel, quassia, or ryania
Streptomycin sulfate and tetracycline
Vitamin D3: As a rodencide
This article was originally published in April 2018 and was updated in August 2019. If there are any corrections or updates that we are missing, please email us at .
Tags: organic pesticides, organic farming, synthetic pesticides, GMOs, organics
Types of Pesticides
There are many different types of pesticides, each is meant to be effective against specific pests. The term “-cide” comes from the Latin word “to kill.”
Algaecides are used for killing and/or slowing the growth of algae.
Antimicrobials control germs and microbes such as bacteria and viruses.
Biopesticides are made of living things, come from living things, or they are found in nature.
Desiccants are used to dry up living plant tissues.
Defoliants cause plants to drop their leaves.
Disinfectants control germs and microbes such as bacteria and viruses.
Foggers (total release foggers) are used to kill insects that are in the open and touch the pesticides.
Fungicides are used to control fungal problems like molds, mildew, and rust.
Herbicides kill or inhibit the growth of unwanted plants, aka weeds.
Illegal and Counterfeit Pesticides are imported or sold illegally.
Insecticides are used to control insects.
Insect Growth Regulators disrupt the growth and reproduction of insects.
Minimum Risk Pesticides are exempt from EPA registration, but many states require them to be registered.
Miticides control mites that feed on plants and animals. Mites are not insects, exactly.
Molluscicides are designed to control slugs, snails and other molluscs.
Mothballs are insecticides used to kill fabric pests by fumigation in sealed containers.
Natural and Biological Pesticides control pests using things found in nature, or man-made versions of things found in nature.
Ovicides are used to control eggs of insects and mites.
Pheromones are biologically active chemicals used to attract insects or disrupt their mating behavior. The ratio of chemicals in the mixture is often species-specific.
Plant Growth Regulators are used to alter the growth of plants. For example, they may induce or delay flowering.
Repellents are designed to repel unwanted pests, often by taste or smell.
Rodenticides are used to kills rodents like mice, rats, and gophers.
Synergists make certain pesticides more effective, but they are not effective when used alone.
Treated Seeds are coated with a pesticide to limit crop damage from fungus and insects.
Wood Preservatives are used to make wood resistant to insects, fungus and other pests.
Last updated January 28, 2020
What Are Organic Pesticides And Are Organic Pesticides Safe To Use
Keeping ourselves and our children safe from toxic chemicals is a no brainer, but not all products on the market are as safe as they purport to be. Organic pesticides are a safer alternative to chemical formulas, but even these need to be used with caution. What are organic pesticides and are organic pesticides safe?
What are Organic Pesticides?
Organic pesticides for plants are considered to be those made from natural ingredients. That doesn’t mean they are free from chemicals, just that the chemicals are derived from botanical and mineral sources. They must still be used carefully, but the chemicals break down more quickly than commercial sources and are deemed less threatening.
Chemicals assault the body at almost every hour of the day. They may come in the air, the food we eat, the products we use on our bodies, and even in our drinking water. Toxic buildup of these chemicals have been shown to cause damage in the body and minimize health. Many of the modern pesticides used today commercially persist in soil for years and compound the store of toxins in our soil, air and water.
There are many types of natural pesticides which are not products of chemical engineering and return to the earth with
less impact and reduced danger. Pesticides for organic gardens must meet certain criteria set forth by the USDA and bear a logo stating they are certified.
Are organic pesticides safe to use in the home landscape? The bonuses with using organic pesticides for plants are their specific target range, slow mode of action, shorter persistence, low residue levels and safer use than conventional pesticides. These attributes are a win-win for consumers and the earth alike, but as with any formula you must pay strict attention to time and mode of application and follow any precautions.
Types of Natural Pesticides
The wide variety of organic pesticides encompasses biochemical, microbial, botanical or mineral based. Many of these come from plants themselves, insects, or naturally occurring minerals.
- Biochemical – Biochemical pesticides are fascinating in their simplicity and sneakiness. Pheromones are one form which is sometimes naturally sourced or manmade. They can disrupt mating behavior and control insect populations.
- Microbial – Microbial agents stem from bacteria, fungi, algae, naturally occurring viruses or protozoans. These either introduce a disease to a certain insect population, produce a toxin or limit reproduction. Milky spore is an example of this type of natural pesticide.
- Botanical – Botanical pesticides come from plants. Nicotine, Neem, Rotenone, Sabadilla and Pyrethrins are all derived from other plants. Pyrethrins for instance, come from the chrysanthemum plant and are effective on flying insects and to flush out larvae and grubs.
- Mineral – Mineral based controls include sulfur and lime-sulfur. Both are sprayed as part of the control of common insect pests.
Homemade Organic Pesticides
Folk wisdom had a cure all for everything before modern technology and science came to the fore. Pest control in the field was accomplished using companion plants and herbs, good cultural practices (such as crop rotation and field burning) or the result of home concocted sprays and dusts.
- Garlic can deter beetles and some larvae. Pennyroyal, feverfew and tansy have excellent repellent properties and add lively color, scent and texture to the garden.
- Encouraging beneficial insects, such as ladybugs and wasps, are a natural way to reduce the populations of unwanted pests.
- Vegetable oil mixed with organic dish soap is a common pesticide useful on small sucking insects.
- Sticky traps are easy to assemble with fly paper and effective in controlling flying insects on fruit trees.
- The internet abounds with homemade organic pesticides and successful methods of controlling insects.
Gardening How-to Articles
By | August 1, 1994
Most yard and garden pesticides available today are synthesized chemicals. Because some of these pesticides have been associated with health and environmental hazards, interest in alternatives has been increasing in recent years.
Microbes are one natural source of pest control. Many bacteria, fungi and other organisms cause diseases that kill or cripple insect pests. These are called microbial pesticides.
Combinations of natural products have also proved effective pest controls. For example, combining vegetable oils with an alkaline substance, such as potassium hydroxide, produces soaps that can be used to control mites and insects. These products are known as insecticidal soaps. Vegetable oils or, more commonly, refined petroleum oils, yield horticultural oils that can be highly effective for pest management.
Plants themselves have proven to be sources of some of the most potent pest-control products. Many plants produce a host of chemical defenses that they use to naturally resist attack from various pests. Some plants are especially rich in chemicals that can be extracted and used for insect control. These products are known as botanical insecticides or, simply, botanicals.
Pesticides derived from natural sources, like those that are manufactured from petrochemicals, have a wide range of effects. Most botanical pesticides, for example, do less ecological damage than synthetics because they break down rapidly when exposed to heat, light and water. Others are as acutely toxic (or sometimes more toxic) than common synthetic garden pesticides. (Acute toxicity is a measure of the damage they can do to you if they’re ingested, inhaled or absorbed through the skin.) All pesticides—synthetic and natural—are regulated as pesticides by the Environmental Protection Agency and the states, and by law must be used strictly in accordance with all instructions on the product labels.
The microbe most commonly used for garden pest control is the bacterium Bacillus thuringiensis, better known as Bt. Different strains of Bt, which occurs naturally in soils around the world, produce toxins that affect different insects. For example, the “kurstaki” strain of Bt (Btk) kills caterpillars, such as gypsy moth, hornworms and cabbageworms. Leaf beetles, such as the Colorado potato beetle, are susceptible to the “tenebrionis” strain (Btt).
To be effective, Bt must be eaten by the pest. Susceptible insects stop eating soon after ingesting Bt, as it destroys the lining of their gut. Death often follows in a few days.
The primary advantage of Bt is its highly selective action. Most Bt products only kill caterpillars that eat it. This means that most beneficial insects are spared the adverse effects. Bt is considered quite safe to humans, and most products can be used right up to harvest.
Bt does have some limitations, however. Because it must be eaten, thorough coverage of the affected plant is critical. Bt also breaks down rapidly upon exposure to sunlight and water, rarely lasting more than a few days. What’s more, Bt kills not only the larvae of pests, but also the larvae of butterflies. Know the insect you are spraying for and keep away from plants where butterfly larvae feed.
Another bacterium long used for insect control is Bacillus popilliae, which produces the “milky spore” disease of Japanese beetle grubs, a major lawn pest. This bacterium has become distributed widely throughout eastern North America, originally through government programs and subsequently by the insects themselves. Milky spore is sold through many garden catalogs.
Microbes may sometimes be used for indirect control of plant pests. Perhaps the best example is the product Clandosan, sold for control of nematodes. This product consists primarily of crab shells and related material that is mixed with the soil. It stimulates the growth of microbes that feed on chitin, the main component of crustacean shells. Nematodes also are covered with chitin and so are susceptible to the microbes as well.
Microbial pesticides are applied as sprays, dusts or granules, just as conventional pesticides are.
Refined petroleum oils have long been used for managing insects and mites. Oils smother insects by plugging the orifices, called spiracles, through which they breathe. They may also be toxic to some insects and mites. Oil products developed for use in pest management are typically referred to as either horticultural oils or dormant oils. They are usually used as sprays, mixed with water in a 1 to 3 percent solution.
The primary problem with oils is that they can damage your plants if used improperly. The first oils to be used horticulturally were the “dormant oils,” which could only be used safely on plants in a dormant state. However, our understanding of what makes oils useful as pesticides and what causes plant injury (phytotoxicity) has increased, and oil products that can be used safely on many plants, even when they’ve leafed out, are now available. Some plants, such as walnut, certain maples and cedar, do remain “oil shy” even to the most refined horticultural oils. Read the label for details on sensitive plants and on when not to spray (spraying under certain environmental conditions can cause injury).
Oils have remained a popular pest-management option because they are quite effective for many difficult problems. They’re most commonly used as dormant sprays to control insects and mites that spend the winter on trees and shrubs. However, the refined oils now on the market are also useful for controlling whiteflies, young scales, mites and many other plant pests present during the growing season. Oils have also proven useful in managing some plant diseases.
Horticultural oils are considered quite safe to humans and other wildlife. Adverse effects on beneficial organisms are also minimal, particularly those of dormant season sprays, which are applied when most beneficial insects are not yet present in the garden. Like soaps, horticultural oils act strictly through contact action and have no residual effects, so thorough coverage is essential.
Soaps have been used as insecticides for over 200 years, but recently their use has increased exponentially. This is largely because there is now a better understanding of which types of soaps make the most effective insecticides, yet do not damage plants.
Insecticidal soaps are applied as dilute sprays (1 to 3 percent concentration) and work primarily by damaging the cell membranes of insects and mites. A wide range of insects are sensitive to soaps—primarily small, soft-bodied species such as aphids, leafhoppers and spider mites. But some larger insects, such as Japanese beetles, are also susceptible. Effects are rapid, usually resulting in death of susceptible insects within a few minutes after exposure. Soaps are sometimes sold in mixtures with other insecticides, such as pyrethrins, to increase their effectiveness.
The selective action of soaps and their high degree of safety to humans are their major advantages. Generally, they have a minimal impact on beneficial species. (One significant exception is that soaps kill predator mites, often an important control of spider mites.) Most insecticidal soaps are registered for use on a wide range of vegetable and ornamental plants.
One of the main limitations of soaps is that they work strictly on contact and have no residual effects. This means that they must be applied directly on the target pests, and so good spray coverage is essential. Also, soaps are more sensitive to certain environmental conditions than other insecticides are. For example, the minerals in hard water react with soaps to reduce their activity. And soaps may be less effective if applied during periods when they dry very rapidly.
Although the insecticidal soaps have been developed with plant safety as a major consideration, some plants are sensitive to soaps and can be injured. Most of these are listed on the product labels under the section outlining hazards associated with use. Indeed, research has also identified soaps that are particularly injurious to plants, and these herbicidal soaps are now marketed as contact “weed killers.”
Many household soaps and liquid dishwashing detergents can be used effectively as insecticides. These should be applied as dilute sprays. Their main disadvantage is that their effects on plants and insects have not been tested and there is a greater chance that they’ll cause accidental injury to your plants.
Alcohol affects many types of insects, apparently by causing them to dry out and die. Although there are no commercial alcohol insecticides, alcohol is an ingredient in some insecticidal soaps and “ready-to-use” insecticides.
Alcohol is often used to control mealybugs on houseplants. Usually, it is applied directly onto the insects with a cotton swab in order to avoid injuring the plant. However, many plants tolerate alcohol well, and insects can be controlled with a spray of alcohol and water in equal parts. Try spraying the alcohol solution on a small part of the infested plant first to make sure it does no damage. If after a few days the plant shows no adverse effects, go ahead and spray the entire plant.
The most widely used of the botanical insecticides are extracts from the flowers of the pyrethrum daisy, Chrysanthemum cinerariifolium. Powdered pyrethrum flowers are rarely sold for pest control, but there are numerous products containing the extracted active ingredients, pyrethrins. Formulations sold for garden use often combine pyrethrins with other ingredients such as soap, diatomaceous earth or rotenone, another botanical insecticide.
Pyrethrins have some unusual insecticidal properties. Perhaps most striking is the rapid “knockdown” effect they have, which causes most flying insects to drop almost immediately upon exposure. Pyrethrins are also highly irritating to insects and can therefore be used as a “flushing agent” to disperse pests. They also rapidly degrade when exposed to light or moisture and so do not persist for long in the environment.
Most insects are highly susceptible to pyrethrins, so quite low concentrations are applied. At the same time, pyrethrins are quite non-toxic to most mammals, making them among the safest insecticides in use. The short persistence and low toxicity of pyrethrum-derived insecticides have enabled federal regulators to permit their use on a wide variety of crops, typically with little or no interval required between application and harvest. Pyrethrins also are among the few insecticides that are cleared for use around food handling and preparation areas.
In the past few decades, synthetic pyrethrins, or pyrethroids, have been developed. The pyrethroids have the basic chemistry of pyrethrins but are synthetically modified to improve persistence, insecticidal activity and other features. Few pyrethroids are available for yard and garden use, although they are used widely in commercial agriculture.
Rotenone is one of the oldest botanical insecticides. Records suggest that it was first used against insects in 1848. (For centuries before that it was used as a fish poison.) Most rotenone is derived from South American species of the genus Lonchocarpus. Rotenone is used most commonly as a dust prepared by grinding the plant roots or extracting the active ingredients and coating dust particles. Several rotenone/pyrethrins mixtures are marketed.
The Environmental Protection Agency has permitted use of rotenone on a wide variety of vegetables and small fruits. It is both a contact and stomach poison to insects. Rotenone is used primarily for control of various leaf-feeding caterpillars and beetles, such as cabbageworms and Colorado potato beetle. Some insects with sucking mouthparts, such as aphids and thrips, are also susceptible to rotenone. It is a relatively slow-acting insecticide, often requiring several days to actually kill susceptible insects, although they stop feeding shortly after exposure.
Gardeners should be aware of the fact that rotenone is the most acutely toxic of the widely available botanicals—more toxic than most common synthetic pesticides. It is moderately toxic to most mammals, and highly toxic to fish and aquatic life.
Ryania is the powdered extract from the roots and stems of the shrub Ryania speciosa, native to South America. It is sold primarily as a wettable powder. Ryania is also available in some combination formulations with pyrethrins and rotenone.
Ryania has shown promising insecticidal action against many insects. It is sold primarily for control of codling moth. Many caterpillars, leaf beetles and thrips also are susceptible to ryania extracts. Ryania affects these insects either on contact or when eaten. However, it has minimal effects on many beneficial insects, so it can be used with these and other biological controls. Ryania breaks down more slowly after application than other botanical insecticides. It is considered relatively non-toxic to mammals.
Sabadilla is an insecticide produced by grinding the seeds of the sabadilla plant, Schoenocaulon officinale. For several years sabadilla products were not available in the U.S. However, they are now sold by several mail-order suppliers, and garden centers have begun to carry sabadilla products as well.
Sabadilla is both a contact and stomach poison and has shown greatest promise against several of the “true bugs,” such as squash bug, chinch bug, harlequin bug and stink bugs. It has proven effectiveness against leaf-feeding caterpillars, Mexican bean beetles and thrips. Use of sabadilla on certain vegetables, including squash, cucumbers, melons, beans, turnips, mustard, collards, cabbage, peanuts and potatoes, is permitted by the EPA..
The ground seeds of sabadilla sold for garden use are considered among the least toxic of the various botanicals. However, sabadilla dusts can be highly irritating to the respiratory tract, often provoking a violent sneezing reaction if inhaled. Be sure to wear a dust mask when applying it and, as with all pesticides, follow precautions listed on the product labels. In addition, several of the alkaloids in sabadilla can cause rapid depression of blood pressure in mammals.
The newest of the botanical insecticides are those derived from seeds of the neem tree, Azadirachta indica. Extracts from neem seeds and other parts of the tree have long been used for pharmaceutical purposes, for example in toothpaste, particularly in India. Recently, neem has received a great deal of attention because it is so safe to humans and has unusual properties against insects.
Sprays of neem applied to leaves often deter feeding. Furthermore, neem apparently affects the hormones many insects need to develop, killing them as they attempt to molt or emerge from eggs. Many leaf-chewing beetles and caterpillars can be controlled with neem insecticides. Aphids and most other sucking insects generally are less susceptible.
Because of its demonstrated safety, neem was recently exempted by the EPA from food-crop restrictions, enabling manufacturers to market it for use on any edible or ornamental plant.
5 Natural Pesticides You Could Use To Grow Your Own Kitchen Garden
Nowadays people like growing their own vegetables and fruits; basically, owning their own kitchen gardens. And, why not? Who wouldn’t love organic produce from their own garden without having to worry about the dangerous implications of harmful chemical pesticides and insecticides? Pesticides are not just toxic to the environment, but also to humans and animals. Exposure to these chemically-loaded pesticides has been associated with serious illnesses and a cause of number of health effects; ranging from respiratory disorders to cardiovascular issues.
If you are thinking, how you would even save your plants from bugs and insects, then you must know that there are some natural wonders present in your kitchen that can make for effective and natural pesticides – they’d be natural and chemical-less. We list down some of our favourite, all-natural, inexpensive, organic methods for making pesticides for your kitchen garden.
1. Neem Leaf
Neem has long been used for its medicinal and culinary properties. It is also known to be used as a deterrent to pests. This medicinal herb has a bitter taste and strong odour that may keep the bugs away from your plants, but non-toxic to animals, birds, plants and humans. It’s best to spray neem oil on young plants where it is said to be effective for about 22 days. Add some neem oil to a dash of liquid soap and some warm water and stir slowly. Add it to a spray bottle and use immediately.
(Also Read – 10 Wonderful Benefits and Uses of Neem: A Herb That Heals)
Neem has long been used for its medicinal and culinary properties
2. Salt Spray
One of the best and most natural ways to make pesticides at home is salt spray. In fact, not only does it help deter pests, it will also help increase nutrition absorption like magnesium and help plants take up vital nutrients like phosphorus and sulphur. You can add some salt in water and stir the solution well. Add it into a spray bottle and sprinkle on the plants. You can also sprinkle salt around the base of your plants, reapplying every week.
3. Onion And Garlic Spray
Take about one clove of garlic and one medium-sized onion and add some water to them. Let it stay for a while before you add a teaspoon of cayenne pepper and a dash of liquid soap to the mix. Use it on your plants to ensure that no bug infests your produce.
The strong smell of onions and garlic help keep bugs away
4. Eucalyptus Oil
The strong smell of eucalyptus oil deters insects and bugs. All you need to do is to spray some oil on your plants and see the results. Make sure you use it regularly.
5. Chrysanthemum Flower Tea
Chrysanthemum flowers are said to hold a powerful plant chemical compound known as pyrethrum. This substance is believed to damage the nervous system of insects and pests. All you need to do is to boil some dried flowers in to a pan full of water for about 20 minutes. Strain, cool and add it into your spray bottle. This solution can be stored up to two months. In order to make it more effective, you can add some neem oil to it.
Save your kitchen garden from bug infestation and grow organic food at the comfort of your home like never before!
This is part four of a four-part series attempting to separate fact from fiction regarding pesticide use on organic farms. In the first installment, we looked at the common claim that organic farms actually use more pesticides and more dangerous pesticides than convention farms through the lens of a few simple observations and talking to actual organic farmers. In part two, we looked at the factoids that have been taken out of context and twisted into a dishonest narrative. In part three, we looked at the special cases of pest control in organic orchards and vineyards. Here, we take a critical look at a widely circulated article purportedly busting myths about organic farming that managed to create a few myths.
For a lot of people, a lot of keyboard warriors, the entirety of their knowledge of pesticide use in organic production comes from a single Scientific American blog post titled “Mythbusting 101: Organic Farming > Conventional Agriculture” written by Christie Wilcox and published on July 18, 2011.
The article sets about to dispel a number of widely held misconceptions about organic farming, but after clearing up the initial misunderstanding Wilcox makes a hash of the whole affair in playing up every “Dog Bites Man” bit of information she comes across for dramatic effect, along with heavy doses of unwarranted chemophobia (and here the dose does make the poison), leaving most readers more misinformed by the end than when they started. This is unfortunate, as we are all hard-wired to accept just-so stories or those that confirm our biases based on little evidence, but once accepted, those just-so stories are notoriously hard to dislodge, with the goalposts for standards of evidence moved down the field as needed in order to maintain a belief that was initially accepted based on flimsy evidence and reasoning.
The errors in the piece are legion, but I’m going to confine myself largely to the section on pesticides, although I can’t help but point out that the entire thing gets off on the wrong foot from the first sentence.
“Certified organic didn’t exist ten years ago. Yet in 2010, a mere eight years after USDA’s regulations officially went into effect, organic foods and beverages made $26.7 billion.”
Certified organic products have been sold in the U.S. since shortly after the formation of Organic Crop Improvement Association (OCIA) in 1985. What the USDA was tasked with was creating a national standard for certification. That began with the 1990 Organic Food Production Act and the National Organic Program Final Rule was first published in 2000. But the OCIA and other groups had been certifying organic farms prior to that. It’s a small thing, but it shows a writer out of their depth.
When informed by her boyfriend at the time that organic farms do in fact use pesticides, Wilcox didn’t want to believe it:
His family owns a farm in rural Ohio. He was grumbling about how everyone praised the local organic farms for being so environmentally-conscientious, even though they sprayed their crops with pesticides all the time while his family farm got no credit for being pesticide-free (they’re not organic because they use a non-organic herbicide once a year). I didn’t believe him at first, so I looked into it: turns out that there are over 20 chemicals commonly used in the growing and processing of organic crops that are approved by the US Organic Standards.
So far, so good. It also sounds like the boyfriend’s farm was a no-till operation with a serious commitment to conservation agriculture principles. Unfortunately, it goes off the rails in the next sentence:
Shockingly, the actual volume usage of pesticides on organic farms is not recorded by the government. Why the government isn’t keeping watch on organic pesticide and fungicide use is a damn good question, especially considering that many organic pesticides that are also used by conventional farmers are used more intensively than synthetic ones due to their lower levels of effectiveness.
ALL pesticides used by ALL farmers on ALL types of farms are subject to exactly the same EPA, state and county rules and regulations. All organic-approved pesticides are available to conventional farmers as well. One of the things that surprised me in researching this story was that I could not find a single organic-approved pesticide that wasn’t used in a significant way by conventional farmers somewhere. The vast bulk of organic-approved pesticides sold are used on conventional farms. That’s not surprising, but my expectation was that for all the talk of some of the mineral and horticultural oils being less effective and more expensive, there would be a list I could put together of products used exclusively on organic farms. I couldn’t. In talking to a range of experts, there wasn’t a commonly used organic pesticide that conventional farmers don’t also find useful under the right circumstances.
Chart by Steve Savage.
The actual volume usage of pesticides on organic farms is recorded by the government as part of their record-keeping on the pesticide use on all farms. It’s just not broken out separately for organic farms. As far as the USDA National Agricultural Statistics Service or CalPIP (the California Pesticide Information Portal) which keeps meticulous records, if you have an organic farm, it’s just a farm and how you market your product is not of interest to them. Your survey information on total pounds used, acres applied to, number of applications, application rates, etc. goes into the database with everyone else’s.
That might be annoying to people who would like to do head to head comparisons (and I include myself in that group) but it’s not a dastardly plot. It’s not a cover-up. Here’s the data on the most widely used pesticides approved for organic in California for the year 2015:
And here are the most widely used pesticides not approved for organic in California that year:
That spreadsheet is available here. (Special thanks to Steve Savage for assembling that data.)
We can see that sulfurs are the most widely used chemicals in California at 5.6 million acres, tied with glyphosate at 5.6 million acres. In 2015, organic acreage in California stood at 790,413. So, even if we were to assume that sulfur was used on every acre of organic production, that would leave 4.8 million conventional acres. Likewise, of the 2.1 million acres where various copper-based products were applied, assuming copper was applied to every acre of organic production – an even less plausible assumption – that leaves copper products applied to at least 1.4 million conventional acres, nearly double organic acreage. Pyraclostrobin, the top synthetic fungicide in California, was only applied to 1.2 million acres, so sulfurs and coppers are applied to more conventional acres than the top synthetic fungicide (at least according to the CalPIP database).
While it’s true that organic farmers use greater applications of these fungicides because the conventional farmers who use them are often complementing them with synthetics, it’s become clear to me that the difference in use has become exaggerated for polemic effect in the organic/conventional debate.
Wilcox blunders on:
According to the National Center for Food and Agricultural Policy, the top two organic fungicides, copper and sulfur, were used at a rate of 4 and 34 pounds per acre in 1971. In contrast, the synthetic fungicides only required a rate of 1.6 lbs per acre, less than half the amount of the organic alternatives.
For starters, there were vanishingly small numbers of organic farms in 1971 – coincidentally the year Chez Panisse was founded and created the first commercial demand for organic produce. As late as 1992, the year of the first survey tracking organic farms in California, there were only 45,493 acres. In 1971, I’d be surprised if there were more than 1000 acres of what we would recognize today as organic farms. That means the outdated application rates she cites for coppers and sulfurs were for the conventional farms of the time. As we can see from the spreadsheet, 3.31 is the upper bound on rates for coppers and the rate for sulfur is 8.89. Anyone who is taking data from 1971 and thinks it tells us anything about pesticide use in 2011 or 2018 doesn’t know what they are talking about.
Also note that the main organic insecticide, Spinosad, is widely used by conventional farmers as well. Dow sells the organic version under the Entrust label and the conventional version (different adjuvants) is sold under the name Success. Spinetoram, a synthetic derivative chemistry, is sold as Radiant.
But now with all of the concern over copper accumulation in soils and the restrictions on copper use from organic certifiers, a new option recently hit the market. It is a low load copper soap called Cueva . Using Cueva instead of Basic Copper Sulfate or Cuprous Oxide cuts the actual amount of copper applied per acre by 90-98%. More importantly, it is so safe it has a very short re-entry of 4 hours compared to the 12-48 hour periods for other popular copper products.
Take the example of Rotenone. Rotenone was widely used in the US as an organic pesticide for decades. Because it is natural in origin, occurring in the roots and stems of a small number of subtropical plants, it was considered “safe” as well as “organic“. However, research has shown that rotenone is highly dangerous because it kills by attacking mitochondria, the energy powerhouses of all living cells. Research found that exposure to rotenone caused Parkinson’s Disease-like symptoms in rats, and had the potential to kill many species, including humans. Rotenone’s use as a pesticide has already been discontinued in the US as of 2005 due to health concerns***, but shockingly, it’s still poured into our waters every year by fisheries management officials as a piscicide to remove unwanted fish species.
Rotenone is an excellent example of a natural substance that is very dangerous, especially if not handled properly — a point Wilcox clarifies in her next paragraph. But as she originally noted, it had been removed from agricultural uses in 2005, so it was no longer a good example of how organic-approved pesticides could be more dangerous than their conventional counterparts, with a 2006 report on botanical insecticides finding that recent amounts used in California had been about 400 pounds statewide. This seems to frustrate her, so she takes a gratuitous and probably unfair swipe at the people who manage lakes in wild lands. The strikethrough and asterisks are further evidence of how far out of her depth she is, without realizing it. See the second installment of this series for a further discussion of the rotenone story.
*** Oh, it turns out Rotenone got re-approved for organic use in 2010. See for yourself.
What Wilcox has stumbled upon here, and didn’t understand, is the Organic Materials Review Institute’s page for rotenone. What she is seeing is that rotenone is on the list of approved products by the National Organic Program. That essentially allows organically-grown imported bananas to be sold under the NOP label. Rotenone has not been re-approved for use by the EPA. And it’s an easy mistake to make. When I followed her link to see for myself, I was confused, because I would have heard that rotenone was back. So I asked some people who would know before shooting my mouth off. That’s not just journalism, it’s pretty good rule of thumb in life.
Rotenone use in the US since 1992.
Just last year, nearly half of the pesticides that are currently approved for use by organic farmers in Europe failed to pass the European Union’s safety evaluation that is required by law. Among the chemicals failing the test was rotenone, as it had yet to be banned in Europe.
This was actually a pretty big deal. Thirteen of twenty seven organic approved substances up for review got the ax in 2009. Important to note, despite the increased application of precaution and higher standards, copper hydroxide, copper oxide, copper oxychloride, copper sulfate, and Bordeaux mixture (copper sulfate and calcium hydroxide) were all re-approved. Another important bit of context: earlier in 2009, the EU had banned 22 conventional pesticides. They were doing an across the board house cleaning, and due to the political climate surrounding both agriculture and chemicals in Europe, the event may well say more about the application of the precautionary principle in Europe than the relative safety of the pesticides pulled from the market. It’s worth noting that of the thirteen organic products that the EU banned, ten are banned in the US as well, with neem oil, lime sulfur, and mineral oil still approved for use in the US.
Furthermore, just over 1% of organic foodstuffs produced in 2007 and tested by the European Food Safety Authority were found to contain pesticide levels above the legal maximum levels – and these are of pesticides that are not organic. Similarly, when Consumer Reports purchased a thousand pounds of tomatoes, peaches, green bell peppers, and apples in five cities and tested them for more than 300 synthetic pesticides, they found traces of them in 25% of the organically-labeled foods, but between all of the organic and non-organic foods tested, only one sample of each exceeded the federal limits.
This is all true, but what does it really tell us? We aren’t given any comparison with conventional produce. We aren’t told if the levels suggest drift from conventional neighbors or cheating. In testing, organic produce routinely are found to have lower pesticide residues. But the tests are only for synthetic pesticides and not all of those either. They current still don’t have a test for glyphosate residues. But they don’t test for organic pesticide residues. The whole thing is such a mess, it’s hard to get worked up about since the vast majority of produce tested finds residues well below threshold levels, and those are set very conservatively.
Not only are organic pesticides not safe, they might actually be worse than the ones used by the conventional agriculture industry. Canadian scientists pitted ‘reduced-risk’ organic and synthetic pesticides against each other in controlling a problematic pest, the soybean aphid. They found that not only were the synthetic pesticides more effective means of control, the organic pesticides were more ecologically damaging, including causing higher mortality in other, non-target species like the aphid’s predators.
Let’s parse this.“Not only are organic pesticides not safe.”As a blanket statement, this is just false. Most organic pesticides are considered very safe. They are all regulated in the same way that conventional pesticides are. Some are more risky than others and were removed from use in 2009 by the EU. Same goes for conventional pesticides.
“They might actually be worse than the ones used by the conventional agriculture industry.” Again, as a blanket statement this is false. Some organic pesticides are more risky than their synthetic counterparts. That’s true. But those products are also used by conventional farmers.
The Canadian study she cited as evidence that organic pesticides are “worse” was a theoretical exercise – not based on any data about how organic farmers actually control aphids in soybeans. Rob Wallbridge, former organic farm inspector and vegetable, berry, and grain producer, current organic agronomist and consultant in Ontario, Canada, pointed out to me that the study did not test actual organic pest control strategies as practices by farmers in the real world. As best as I’ve been able to gather, that true.
So, the evidence that organic pesticide use is more dangerous is application rates of sulfur from 1971. An insecticide that was phased out starting around a decade earlier (from 2011) and then banned by the EPA in 2005. The EU removed a number of products in 2009, ostensibly to make organic farming safer, as they also did that year for 22 synthetic products. And a laboratory study that shows that two organic pest strategies that nobody uses could possibly be worse for the environment three conventional products.
And notice how the at each step of the way the particular becomes universal. “Rotenone was banned in 2005, but is a good example of how dangerous natural compounds can be” and “Some risky organic pesticides were taken off the market” turns into “Not only are organic pesticides not safe” ignoring that the not safe ones were just removed but applying that property to the remaining organic pesticides that are considered relatively safe. Which in turn gets “They might actually be worse than the ones used by the conventional agriculture industry.” layered on top of it. But that’s spreading a little too much mustard on the sandwich. An organic pesticide can have a somewhat worse risk profile than a synthetic counterpart and also be relatively safe. It also might be applied to more conventional acres than organic. Which is the point of the first chart. There’s no need to fear monger to get the point across that some organic pesticides have higher risk profiles than their synthetic counterparts. The vast majority of pesticides used today are Category IV “essentially non-toxic”.
CORRECTION: The initial draft as published took issue with Ms. Wilcox’s opening sentence,“Certified Organic didn’t exist ten years ago. Yet in 2010, a mere eight years after USDA’s regulations officially went into effect, organic foods and beverages made $26.7 billion.” I pointed out that organic farms had been certified by various agencies since 1985, and it was only the USDA’s National Organic Program that went into effect eight years prior.
A reader pointed out that in the capitalization of C and O shows that she was referring to the NOP label in particular and not to organic certification in general. I regret the error – MB
POSTSCRIPT May 26, 2018:
It has been brought to my attention that at the time Scientific American published a response to Christine Wilcox’s “Mythbusting 101: Organic Farming > Conventional Agriculture“ by an urban organic farmer named Jason Mark titled “Myths: Busted–Clearing Up the Misunderstandings about Organic Farming” and then a response to Mr. Mark by Ms. Wilcox, “In the immortal words of Tom Petty: “I won’t back down” where she manages to pile on more errors.
She tried to compare the top organic insecticide to the top conventional insecticide and the top organic fungicide to the top conventional fungicide but ended up doing two insecticide vs. fungicide comparisons.
She used the LD50 of the compound copper sulfate which is only used as an aglaecide (sused to kill algae) rather than the LD50 of an copper based fungicide formulations approved for use in agriculture (they are all much lower). The LD50 of Basic Copper 53 , a very popular product, is 1502 mg/kg, much less toxic than straight copper sulfate at 30 mg/kg. (Remember, the higher the number, the lower the toxicity.)
The correct comparisons show organic fungicide to be more toxic than the conventional fungicide, and the organic insecticide less toxic than the conventional insecticide. (OA = organic approved)
Basic Copper 53 (OA): 1503 mg/kg
Chlorothalonil: 10,000 mg/kg
Pyrethrins (OA): 200 mg/kg to greater than 2,600 mg/kg (Pyganic, perhaps the most popular pyrethrins is 2000 mg/kg
Chlorpyrifos: 95 to 270 mg/kg
Here are some match ups from our spreadsheet above of the most widely used chemicals.
Copper hydroxide (OA): 1000 mg/kg
Pyraclostrobin: 5000 mg/kg
While both copper hydroxide and pyraclostrobin are considered moderately toxic pyraclostrobin is significantly less toxic . However, looking at insecticide match ups, spinosad, like pyraclostrobin is at the lower bound of moderately toxic, on the tipping point of slighly toxic where we find stylet oil and Bt, while the top three insecticides are highly toxic. In fact, abamectin is considered extremely toxic.
Nor does she address that conventional farmers use those organic pesticides.
Here are some Environmental Impact Quotient (EIQ) comparisons (the lower the number, the lower the impact) for rotenone and a few other relevant insecticides.
Bt – 8
Spinosad – 17
Pyganic – 18 (pyrethrin based)
Rotenone – 33
Abamectin – 38
Imidachlorprid – 37
Chlorpyrifos – 43
Disulfoton – 104
It remains the case that for a lot of non-ag readers the initial blog post was essentially the source of bulk of what they thought they knew about organic pesticide use and people continue to share the link to this day as evidence that organic pesticide use is more concerning than conventional use.
Marc Brazeau is the GLP’s senior contributing writer focusing on agricultural biotechnology. He also is the editor of Food and Farm Discussion Lab. Follow him on Twitter @eatcookwrite
Organic pesticides not always ‘greener’ choice, study finds
A new University of Guelph study reveals some organic pesticides can have a higher environmental impact than conventional pesticides because the organic product may require larger doses.
Environmental sciences professor Rebecca Hallett and PhD candidate Christine Bahlai compared the effectiveness and environmental impact of organic pesticides to those of conventional and novel reduced-risk synthetic products on soybean crops.
“The consumer demand for organic products is increasing partly because of a concern for the environment,” said Hallett. “But it’s too simplistic to say that because it’s organic it’s better for the environment. Organic growers are permitted to use pesticides that are of natural origin and in some cases these organic pesticides can have higher environmental impacts than synthetic pesticides often because they have to be used in large doses.”
The study, which is published in the journal PLoS ONE, involved testing six pesticides and comparing their environmental impact and effectiveness in killing soybean aphids — the main pest of soybean crops across North America.
The two scientists examined four synthetic pesticides: two conventional products commonly used by soybean farmers and two new, reduced-risk pesticides. They also examined a mineral oil-based organic pesticide that smothers aphids and another product containing a fungus that infects and kills insects.
The researchers used the environmental impact quotient, a database indicating impact of active ingredients based on such factors as leaching rate into soil, runoff, toxicity from skin exposure, consumer risk, toxicity to birds and fish, and duration of the chemical in the soil and on the plant.
They also conducted field tests on how well each pesticide targeted aphids while leaving their predators — ladybugs and flower bugs — unharmed.
“We found the mineral oil organic pesticide had the most impact on the environment because it works by smothering the aphids and therefore requires large amounts to be applied to the plants,” said Hallett.
Compared to the synthetic pesticides, the mineral oil-based and fungal products were less effective, as they also killed ladybugs and flower bugs, which are important regulators of aphid population and growth.
These predator insects reduce environmental impact because they naturally protect the crop, reducing the amount of pesticides that are needed, she added.
“Ultimately, the organic products were much less effective than the novel and conventional pesticides at killing the aphids and they have a potentially higher environmental impact,” she said. “In terms of making pest management decisions and trying to do what is best for the environment, it’s important to look at every compound and make a selection based on the environmental impact quotient rather than if it’s simply natural or synthetic. It’s a simplification that just doesn’t work when it comes to minimizing environmental impact.”
There has been a growing trend in the recent decades for individuals and companies to “go green” or be more environmentally friendly. There has also been a sentiment that natural and organic products are healthier or safer. The pest control industry has responded to these changes in our culture and business markets with innovations in products, materials, and methods.
Requests for “organic” based services have grown to a point where most pest control providers offer services that use only natural pesticides. However, words like, organic, natural and green have started to become cliché. So what does it really mean in regards to pesticides? For the sake of clarity, natural pesticides refer to products that are derived strictly from sources in nature with little to no chemical alteration. Synthetic pesticides are products that are produced from chemical alteration.
RELATED: Green Is the New Clean: Eco-Friendly Pest Control
As in most industries, consumers have numerous choices. Many may ask themselves, “what is the right choice for me and my family or my business?”. Here are some things to consider when making a choice between natural and synthetic pesticides:
All Pesticides Are Toxic
The suffix -cide is latin for killer (pesticide means killer of pests). There is an assumption that natural pesticides are safer, healthier, or more environmentally friendly than synthetic products. Yet the underlying truth with natural pesticides is that they are still toxic substances to some degree. In fact, some naturally procured pesticides are deadlier or carry a higher risk than synthetic options.
Nicotine is a good example. Nicotine is a substance that is naturally produced by some plant species (most notably tobacco). They do so, for the purpose of defending themselves from insects. However, it is hazardous to most other organisms, in relatively small quantities. Although completely natural, nicotine can be very deadly.
Many synthetic pesticides today are designed to target specific species. Therefore, they carry little health risk for non-target species. What is toxic for an insect may have little to no effect on a mammal. On the flip side of this argument, there is due cause for concern when some synthetic pesticides are known to be carcinogens, teratogens, or mutagens. Yet, it is important to note that this is not true of all synthetic or artificially created pesticides. As previously stated, the intent of pesticides is toxicity, but often, the risk is reduced by the way it is used.
Integrated Pest Management (IPM)
Integrated Pest Management (or IPM) has become the cornerstone of the pest control industry. IPM employs several different tactics to control pest issues, after properly identifying the pest and determining the level of pest infestation. The use of mechanical traps, habitat alteration, and exclusion methods result in a lesser reliance on pesticides in general. If rodents can be efficiently trapped or excluded from the building, there is less of a need for rodenticides to be used. If an area can be sanitized of attractive food sources, there is little or no need of insecticides to kill roaches and flies. Utilizing several tools for the control of pests means pesticides can be used more sparingly, instead of the “spray and pray” method of previous generations.
When pesticides are needed as a tool in the full spectrum of control, they are used responsibly, in smaller quantities, and in targeted areas. In regards to structural pest control (in homes and commercial buildings), most material applications do not require a pesticide to be sprayed in a widespread or open area. In fact, minuscule amounts are used and typically placed in cracks and crevices where most insects like to hide. This drastically reduces pesticide exposure to a building’s inhabitants. With this in mind, the difference in natural or synthetic is almost negligible. This is because neither material is accessible if used correctly.
Both natural and synthetic pesticides are effective at controlling pests. However, their modes of action can differ greatly. They often result in a drastic difference in the length of time it takes to see the intended results. Pest management professionals often get requests from their organic clients to “use the good stuff” (meaning synthetic pesticide option). This comes after some frustration with dealing with an infestation longer than expected. Synthetic pesticides often act quickly because they are chemically engineered to target and disrupt specific biological functions within the intended pest. While natural or organic pesticides will also work if given enough time and patience. The down side with natural options is that it may require more visits and multiple applications to achieve the same result. Many folks who are dealing with a pest infestation, seem to prefer the issue to be resolved quickly. They are unwilling to wait for the organic materials to do their job.
Requirements or Mandates
In many industries, consumers are given a vast array of choices in products and services. Under certain situations, the choices are limited due to requirements from 3rd party authorities. In the pest management industry, organic or natural pesticides may be required in order to comply with a client’s goal of meeting a set of standards or regulations, such as the USDA National Organic Program. The elimination of pesticide use or the use of natural pesticides may be mandated by the program standards so that a supplier can label and market their goods as “organic”.
In recent years, varying levels of government have passed laws and ordinances to restrict the use of pesticides for homes and businesses. The town of Ogunquit, ME passed such an ordinance in 2014 that restricted the use of synthetic pesticides on the exterior of businesses and private homes. Similar ordinances have been proposed or passed in other towns and cities in the state. Although the intent of these legislative measures is to do good, the result is fewer choices for resolving pest problems. Even for trained professionals.
In some situations, “organic” materials are a necessity. But for the average consumer, the choice lies strictly with their preference and conviction. The confusion of consequences from the widespread use of pesticides in decades past has produced a weary and concerned culture today. Understandably, so. However, improvements in science and pest management industry standards, practices, and training have not eliminated, but considerably reduced the negative effects of pesticide use. The key takeaway is that all pesticides should be used with caution and respect, whether or not they are of natural origin.
With the growing demand for organic foods in the U.S., there has been a backlash from agribusiness groups, companies and individuals who see organic as a threat to their interests. These critics accuse the organic industry of using deceptive marketing practices to get consumers to pay more money for organic food. Another line of attack has been that organic farmers use lots of pesticides, some of which are more toxic than those used by conventional farmers.
The reality is that some organic farmers do use pesticides but such products are primarily derived from natural substances, go through a strict regulatory approval process to ensure they are not harmful to the environment and human health and are only allowed to be used when other pest control methods aren’t successful.
The fact is that the organic farming and food movement is based on producing healthier foods without the use of toxic pesticides.
25 Organic-Approved Synthetic Pesticides vs. 900 Conventional
However, organic farmers, like their conventional counterparts, face challenges with weeds, insects and diseases. To help address those challenges, the National Organic Program allows the use of certain natural-based and synthetic substances as pesticides. The National Organic Program’s National List of Allowed and Prohibited Substances details about 25 synthetic products that are allowed to be used in organic crop production. These include alcohols, copper sulfate and hydrogen peroxide. By contrast, there are some 900 synthetic pesticides approved for use in conventional farming.
There are also many natural-based substances used as pesticides that are allowed in organic farming. These include neem oil, diatomaceous earth and pepper.
“When you look at the substances themselves and not at the use rates, organic represents the least toxic set of substances,” said Nate Lewis, farm policy director at the Organic Trade Association. “The difference is pretty striking.”
Most pesticides allowed for use in organic farming are derived from plants or bacteria. “They have their roots in nature,” said Charles Benbrook of Benbrook Consulting Services, an organic consulting firm.
The majority of organic-approved pesticides are used in fruit and vegetable production, said Lewis. Very few are used in organic grain production.
“Least Toxic Pesticides Available”
According to Lewis, pesticides approved for organic crop production must go through the most rigorous review of all pesticides. All pesticides must first be reviewed by the U.S. Environmental Protection Agency (EPA) to determine their toxicity. EPA sets tolerances, “which are the maximum amount of a pesticide allowed to remain in or on a food.” If it is a synthetic pesticide to be used for organic farming, the National Organic Standards Board then reviews it and will recommend whether or not to allow it to be added to the National List. Then, the Organic Materials Review Institute (OMRI) or the Washington State Department of Agriculture will review the product to ensure it complies with the national organic standards.
According to Lewis, just one synthetic pesticide approved for organic farming has been assigned an EPA tolerance—spinosad, an insecticide derived from a soil microorganism. Other synthetic pesticides on the National List, as well as the natural-based substances, are considered safe enough that they don’t even need an EPA tolerance.
“The EPA considers organic-approved pesticides to be the least toxic and most safe pesticides, so safe they don’t even need to establish a tolerance for what’s healthy or what’s safe on crops,” Lewis said.
One of the most widely spread myths about organic-approved pesticides is that organic farmers use Rotenone, a broad-spectrum insecticide known for its toxicity. While it has been used in the past, the current reality is that the EPA has banned Rotenone for use in the U.S, though Lewis says it is still used in some countries that grow organic bananas. “The NOSB has passed a recommendation to prohibit it outright. We are awaiting NOP action on that.”
Critics also cite the use of copper-based pesticides, which are used as fungicides in organic and conventional fruit production.
Copper does have issues. Kelsey McKee, OMRI’s review program and quality director, cites documents from the U.S. Department of Agriculture and EPA that describe concerns with the use of copper.
“In general, these concerns include adverse effects on soil microorganisms as well as adverse effects on human, aquatic and terrestrial life during farm level application or from residuals in food,” she said.
In an October 2015 review of copper, the National Organic Standards Board acknowledged that it is “both harmful in the environment when misused and absolutely necessary to grow many crops to protect against disease.”
The National Organic Standards Board called for additional study on copper for the next review of the material to see if it should continue to be on the National List.
In a comment to a Scientific America article on organic pesticides, Rob Wallbridge, an organic farmer in Quebec, said that copper is not absorbed by plants and washes off “which is good for risk of consumer exposure.” He also said that organic certification standards “require monitoring and restrict producers from using copper sulfate if copper is accumulating in the soil at excessive levels.”
Copper is also exempt from an EPA tolerance and is an essential nutrient, according to Brian Baker, consultant at Belcairn Concerns and former research director at OMRI.
Baker emphasizes that conventional farmers also use copper. “If they think it is so bad, why don’t they stop using it?”
Pam Marrone, CEO and founder of Marrone Bio Innovations, agreed. “Organic growers get flak about copper, but conventional farmers use a lot more copper than organic farmers.”
She also said the copper formulations used by conventional farmers contain higher risk inert ingredients than formulations used in organic production. “The inert ingredients in organic approved copper have to be on the approved list for organic and are food-grade and low risk,” she said.
Marrone, whose company develops biopesticides for organic production, said there are organic and OMRI-approved alternatives to copper on the market. These include Zonix and Polyversum and her company’s Regalia. The OMRI Products List also includes non-synthetic alternatives such as biological fungicides and botanical extracts such as cinnamon oil and clove oil.
Foliar Spray Bt Not the Same as GMO Bt
Then there is the debate over organic-approved Bt insecticide versus genetically engineered Bt crops. Critics say the organic industry is hypocritical by allowing the use of a foliar Bt spray to kill insects while opposing GMO crops containing genes from the Bt or bacillus thuringiensis bacterium.
Benbrook called such criticism spin. “It’s a completely different situation. Bt toxins in GM sweetcorn are inside the kernel and remain there when the corn is cooked and eaten. People who eat that sweetcorn will get a high dose of Bt toxins.”
By contrast, the Bt foliar spray breaks down quickly and doesn’t remain on the plant. “There is zero human exposure to foliar Bt spray,” Benbrook said. “Implying that the GMO Bt is the same as the foliar spray is a lie.”
Pesticides May Be Used Only as a Last Resort
Perhaps the most important point in the discussion about the use of pesticides in organic agriculture is the fact that the organic rules require that approved synthetic pesticides be used only as a last resort.
“The standards say you must apply practices like having cover crops and crop rotations and things that create health in the whole ecosystem and your farm,” said Dag Falck, organic program manager, Nature’s Path. “After you’ve demonstrated and documented to your certifier that you’ve done these steps, if they are not adequate to control the problem, then only are you allowed to use things from the National List.”
According to Falck, many organic farmers don’t even consider using synthetic substances from the National List. “They say, ‘that’s not how I do things,'” he said.
For many consumers pesticide residues on food are a big concern and organic foods have been shown to contain far less pesticide residues than conventional foods. Benbrook, who has done extensive work on pesticide residues in organic foods, said: “When you compare organic versus conventional food, it is absolutely inarguable that organic food reduces dietary exposure to pesticides by 98 percent.”