The World of Biorational Controls

It wasn’t that many years ago that organic and natural pesticides were virtually non-existent in the retail sphere, so home gardeners, hobby farmers and the like had to make difficult decisions about the products they used. Thankfully, that’s changed greatly and nowadays we have a world of biorational controls to choose from.

There’s no hard and fast definition of biorational controls; the term covers products that have a reduced risk to living things and have little to no impact on the environment. This characterization is especially important when discussing pest control, fungicides and herbicides – all of which have an over-representation of toxic products on the market. Biopesticides (biological pesticides) and biofungicides (biological fungicides), certain minerals, botanical extracts, herbicides and soaps all fall within the biorational parameters. 

Biopesticides/Biofungicides 

Beauvaria bassiana at work

This is arguably the category that’s seen the most innovation in the last 10 years or so. There are many types of biopesticides these days, including:

• Insecticides that use entomopathogenic fungi to kill specific groups of insects, like Beauvaria bassiana which infects a wide range of insects with deadly white muscardine disease and Isaria fumosorosea Apopka Strain 97 that kills mites and soft-bodied insects.

• Insecticides that use targeted strains of bacteria to kill specific insects, like Bacillus thuringiensis israelensis (Bti) that kills mosquito larvae, and Bacillus thuringiensis kurstaki (Btk), which kills Lepidoptera caterpillars.

• Insecticides that come from plant-derived oils and their extracts like Neem Oil and

Pyrethrins. Neem comes from the Neem tree, a native to the Indian subcontinent; it will kill soft-bodied insects and is also useful as a deterrent or repellent. Pyrethrins come from the Chrysanthemum cinerarifolium, a daisy, and can be used to control both soft-bodied and hard-shelled insects.

Biofungicides also use a variety of beneficial microorganisms to control plant pathogens like powdery mildew and botrytis. They work in multiple ways, but generally speaking they overpower the pathogens and out-compete them for resources. The ingredients in some common biofungicides include:

Bacillus subtilis

• Bacillus amyloliquefaciens strain D747, a naturally occurring soil bacteria

• Bacillus subtilis – a bacteria found in the soil and the gastrointestinal tract of certain animals

• Trichoderma – This is a group of soil-dwelling fungi of which certain strains have been developed for maximum efficacy in the plant world. 

• Inorganic compounds like potassium bicarbonate, the active ingredient in Milstop 

• Botanical oils like the Thyme Oil in Thymox Control Organic.

These are deeply researched and complex products that are, nevertheless, easy to use and readily available to any size grower. I strongly encourage you to dig deeper into these categories; there are many products than I have pointed out and there is much more information on each product page. 

Biopesticides and biofungicides are excellent choices for IPM program and because they often only affect targeted pests, using them reduces the effects to non-target organisms. These products also cut down the danger of residual pollution and eliminate the problem of pesticide/fungicide resistance. They are also cost-effective overall as they reduce the need, and thus the cost, of conventional products.

Minerals

Rice Terraces in Southern China

Mineral-based biorational controls are often products that have been around for a long time but are getting new respect as the interest in safe and natural solutions grow. For example, the use of kaolin clay for pest control dates back over 2,000 years. It works as a crop protectant and will also repel pests, cause irritation and confusion, and create an obstacle for feeding and egg-laying. The popularity of the kaolin clay product we carry, Surround WP, shows that modern consumers still see the value in this biorational mineral. Diatomaceous Earth (DE) has been used in China for 4,000 years. DE comes from the fossilized shells of microorganisms known as diatoms that has been crushed into a fine dust. It has innumerable microscopic sharp edges that cling to insects as they pass through it and mortally wound them by cutting up their exoskeletons. It will also absorb the waxy cuticle around the insect, which causes it to dehydrate and die in as little as 48 hours.

Botanical Extracts

Talk about a product line that has exploded in the last few decades! Using botanical oils for pest control is another case of an ancient-but-still-excellent method. Mineral biorationals  may have changed very little over millennia,  but oils have enjoyed a renaissance as newer, more target-specific and user-friendly formulas have been developed. Botanicals can now be found in pesticides, fungicides, bactericides and repellents. For more information on some of the most commonly used botanical extracts, check out my blog on the subject here. Happily, the use of botanicals is becoming main-stream; they’re easy on the environment in general and their use falls well within the principles of IPM.

        Herbicides

We have come a long way from spraying highly-toxic herbicides like DDT all over everything. Nowadays most people understand the need to keep weed control products, not just weeds, in check.  Biorational herbicides use a wide variety of ingredients to great effect. We carry herbicides that use corn gluten meal, botanical oils, iron, barrier controls, d-limonene (citrus oil), ammonium nonanoate (BioSafe Weed & Grass Killer) and citric acid. Biorational herbicides will not produce the quick knockdown of weeds that the toxic sprays can, but they are still highly effective for the patient and conscientious consumer.

           Soaps

Biorational insecticidal soaps are another product line that reflect the modernization and upgrade of an old school DIY form of pest control. Insecticidal soaps these days are potassium salts of fatty acids and are used to control soft-bodied insects and some path pathogens. One of our customer-favorite soaps is M-Pede, which, in addition to its insecticidal properties, is labeled as a curative control for powdery mildew.

As far as our pest control products go here at ARBICO, we have very few that cannot be classified as  biorational (traps come to mind). There are still some hard-to-kill pests that we struggle to find biorational controls for, but we are committed to finding as many as we possibly can and presenting them to you as soon as we do.

Submitted by Pam

Oils For Pest Control - Essential, Botanical, Whatever...

Essential oils are the driving force behind many of the nature-based pest control and fungicide products in the retail world today. Sometimes called botanical oils or horticultural oils, the distinctions between essential and botanicals can be semantic, non-existent, or formulation-driven. Horticultural oils, on the other hand, are generally mineral oils and not plant-based. Essential oils are derived from various plants and have been used to combat pests for hundreds, if not thousands, of years. Neem oil, for instance, is a product of the Neem tree and has been used in India since ancient times. Essential oils work in many ways to control pest creatures and fight pathogens: they smother insect pests, they coat plant surfaces and suppress fungal growth, they breakdown insect exoskeletons, they disrupt reproductive cycles and they are excellent repellents. Sometimes all the different oils can be overwhelming to consider; I’m going to go over some of the products we carry to (hopefully) ease some of that.

Before I go any further, I’d like to address the seemingly infinite websites and articles devoted to essential oils. A quick search will show that most of these relate to health and beauty usages, but there are also a great many that tout DIY essential oils for pest control. I am personally a big fan of most DIY projects, but there are several good reasons that this is not the way to go with pest control:
• When it comes to insect control, oils need to come into contact with the insects and their larvae in order to be effective. This is just not practical, or even possible, when trying to apply via droppers, cotton balls, etc. Additionally, most insects are small and really good at hiding and running, so just finding them can be tricky. Not to mention that, once you have an infestation you need much more than spot treatments.
• To use essential oils as a fungicide, you need to cover all the plant surfaces. Without using the proper formulation and spraying techniques this type of application is impractical and possibly harmful to plants.

• In order to get to all the insects and pathogens as described above, you need to get your oil to spread. Essential oils are not necessarily runny in the right ways. You may need to add a spreader-sticker or similar adjuvant to get it to all the right places. This means an extra step, additional expenses, and real formulation skills.
• Many of these oils are toxic. When used in their undiluted state they can cause skin problems and can be very dangerous to pets (especially cats).
• Essential oils are expensive. Additionally, most essential oils work best when using in combination with other oils. You could spend a not-so-small fortune in oils trying to come up with the right formula.
• Mass-produced essential oils are not regulated, so their inputs and formulation processes cannot be relied upon to be as pure as you might like, much less organic.

The solution to all of the above concerns is to know an oil's strengths and weaknesses and then choose a well-vetted, professionally-developed oil product that has been designed for maximum efficiency, ease of use, and affordability. Luckily, there are lots of good choices out there that you can rely on worry-free.

Castor Oil: This oil is derived from Castor Beans from the Ricinus communis plant and has been used as a repellent for a very long time. These days, Castor Oil is used as the main ingredient in the most popular mammal repellents out there, but it also appears on the ingredient lists of some insecticides as a deterrent ingredient. We carry a number of products with Castor Oil in it (see here), including IV Organic 3-in-1 Plant Guard, which protects trees and plants from environmental extremes and mammal and insect pests. To read a profile of Castor Oil from Cornell University, go here.

Cedarwood Oil: 

This powerfully aromatic oil comes from the wood of two different tree species, Junipers (Juniperus spp.) and Cypresses (Cupressus spp.). While most people find this particular smell appealing, this is not the case for many crawling and flying creatures; they simply don’t like it. Take a look at our products that contain Cedarwood Oil here to see the variety of pests it repels. For example, Mosquito Magician relies on 3% Cedarwood Oil in its highly effective formulation. To read a profile of Cedarwood Oil from Cornell University, go here.

Lemongrass Oil:
This is another extremely fragrant oil, so much so that you can find it in perfumes and air fresheners. Produced from the perennial grass Cymbopogon, this oil has insecticidal, fungicidal, and repellent properties. Within our product offerings, Lemongrass Oil is rampant in our mosquito control products. With its pleasant scent and powerful repelling capabilities, it makes a great alternative to the nasty chemical smells of traditional mosquito repellent. Medella Naturals™ Insect & Mosquito Repellent Spray is a great example of this, it smells so good you will want to spray it everywhere you go. To read a profile of Lemongrass Oil from Cornell University, go here.

Peppermint Oil:
Peppermint is a natural hybrid that is a cross between Spearmint and Watermint. The distinctive smell of oil from these leaves is another example of a scent that humans enjoy but insects and mammals find quite the opposite. Peppermint is often touted as a repellent for everything from mice to spiders, but in truth, it has limited efficacy on its own; it’s best when combined thoughtfully with other essential oils. Review some of our products that contain Peppermint Oil (here) to see the ways in which this is done. For instance, Essentria IC-3, a highly popular and extremely effective insecticide, contains 1% Peppermint Oil in combination with Rosemary Oil and Geraniol. To read a profile of Peppermint Oil from Cornell University, go here.

Rosemary Oil:
This particular oil comes from the same plant (Rosmarinus officinalis) as the seasoning you may have in your kitchen. While it undoubtedly adds deliciousness to your food (yum, Rosemary Chicken!), it is also a potent insecticide for soft-bodied insects. Rosemary Oil works a suffocant and will also breakdown the body of the insect. Like Peppermint Oil, Rosemary Oil is enhanced in blends with other oils. Here are some of our best products containing this useful oil. In particular, I recommend that you take note of SNS 217; it contains a lively amount of Rosemary Oil at 10%. To read a profile of Rosemary Oil from Cornell University, go here.

Thyme Oil:
This is another oil from a kitchen-familiar herb, Thyme (Thymus vulgaris). This oil has multiple amazing abilities – it works much the same as Rosemary Oil, but it also does all that to fungal pathogens. In recent years, we have come across some outstanding Thyme Oil products, notably Thyme Guard and Trifecta. Thyme Guard is a first-rate pesticide/fungicide/bactericide that contains 23% Thyme Oil (the highest of any comparable product out there) and lets the strength of that carry it as its sole active ingredient. Trifecta is also a 3-action product, but it contains 14% Thyme Oil in a medley of other oils. Both are excellent choices to get control of hundreds of insects and pathogens on plants. To read a profile of Thyme Oil from Cornell University, go here.

You may have noticed the lack of organic certifications on the products I’ve mentioned. There are some certified organic essential oil products available (here are some of ours), but the lack of regulations that I mentioned before makes it difficult for manufacturers to source and develop wholly organic oils. While many do, the process is complicated and costly enough to keep others out of that fray. What reputable developers do instead is craft their products as sustainably and cleanly as they can. If this is a concern for you, your best bet is to do your homework on any product and/or manufacturer.
                                                                                                                       
                                                                                                                               

Take care out there.         
    Submitted by Pam