Sunday, May 19, 2013

The Yin and Yang of Pest Control

The most important concept to remember is that weeds proliferate in unbalanced soils, and insects and diseases feed on unhealthy plants. A garden or field full of pests is not normal.
Once you know that, it’s all about implementing the steps in this book. When we stop spraying toxins, provide sufficient water, increase humus and improve the soil food web, balance soil nutrients and ensure there is proper energy in the system, pests go away. 

- Phil Nuata  (The Holistic Gardening Hardbook)

If you really want a full understanding of pathogenis response in plants An Overview of Plant Defenses against Pathogens and Herbivores provides an easy to understand yet in depth view of how plants fend for themselves.

I took my bug zapper down after finding praying mantis, and lace wings stuck to the wires.  Zappers kill indiscriminately.  I found it interesting that spiders figured out that there are a lot of bugs by the light. The webs were thick near the zapper.  It stands to reason that a high concentration of bugs will attract other beneficial insects into the killing zone as well.

Zapping the good guys is not good, and tiny insects like whitefly and aphid are probably too small to be zapped anyway.

So far my garden is doing well with nothing but compost tea.  I bought some insect frass and BT (Bacillus thuringiensis) several weeks ago, but I have not used it yet. The beneficial insects, and the good health of my plants seems to be enough so far.   I had a lot of aphids for a short while, but then the ladybugs flew in, and ate them.  It was beautiful.  I had hundreds of ladybugs come to my garden and then most of them left after the aphids were gone.  They laid a lot of eggs, and I had lots of baby ladybugs too.

insect frass contains chitin which stimulates the plant's auto-immune system to create plant secondary metabolite s (PSM s or “exudates ”) such as Chitinase Enzyme, Terpenes, Flavinoids, Alkaloids and Amino Acids, which protect plants from Pests and Pathogens
Plants often wait until pathogens are detected before producing toxic chemicals or defense-related proteins because of the high energy costs and nutrient requirements associated with their production and maintenance. This phenomenon is called systemic acquired resistance (SAR) and represents a heightened state of readiness in which plant resources are mobilized in case of further attack. Underground messaging systems also allow neighboring plants to invoke herbivore defenses before attack. Researchers have learned to artificially trigger SAR by spraying plants with chemicals called plant activators (insect frass ). These substances are gaining favor in the agricultural community because they are much less toxic to humans and wildlife than fungicides or antibiotics, and their protective effects can last much longer.

Ants can be particularly difficult but Keveen Gabet  wrote this in his article Ants – From Warship to Worship (Mexico).

Despite the few occasional bites and their compulsive leaf-cutting and seed-robbing habits, ants are wonderful allies. If you find the mother nest, you will be blessed with a mound of great compost-like soil as well as tiny gravels that will improve soil drainage. Now that’s a great bonus. They also offer long hours of entertainment; watching them fight other colonies, communicate or carry bulky items is like entering a Nat Geo documentary for a bit. As for their destructive temper, I guess all they want is food. If food it is they want, food they shall have!

Mango peels to keep my ants pacified
I now have opted for a more conscious approach and instead of making them my enemies, I have declared them worthy of my adoration. Everyday, I spread a bit of our food (fruit peels and sugary stuff like raisins for instance) close to their nest or on their way to my garden as my offering. I do it almost ritually just because it’s fun.
Overall, I call it a multilateral success as peace reigns over our little oasis once again, and they seem to have lost interest in ‘my’ share of the garden. 

I planted quite a few beneficial plants to attract bugs.  I have asylum, nasturtium, poppy, and marigolds scattered throughout my garden.  I love to spend my time in my beautiful garden of vegetables, flowers, bees and I'm willing to let the bugs eat some of my crop knowing that there is balance.

Please be careful not to kill the pollinators. Modeled after nicotin,  neonicotinoids only sound natural and safe.
"Scientists studying the massive global bee die-off have unearthed a slew of evidence on the devastation across the food chain caused by the most widely-used pesticide on Earth, neonicotinoids. Once they enter the water supply, neonicotinoids wipe out dragonflies, snails and other waterborne life. The few hardy species that survive are left so toxic that they're killing birds -- and Lowe's and Home Depot are putting this toxic product right in our back yards. ... Up to a third of all honeybees vanish each winter, beekeepers are saying that we are "on the brink" of not being able to pollinate all our crops."-(Sum Of Us)
Insecticides such as Acetamiprid, Thiacloprid, Methiocarb, Abamectin, Imadicloprid are forms of neonicotinoids.

I hope everyone will go to this site  (Sum Of Us) and sign the petition 
and discourage the use of bee-poisoning neonicotinoids. 

Sevin and many other insecticides including bifenthrin, and permethrin (Eight), will kill the Aphids but also are deadly to many beneficial insects such as bees, other pollinators, and Lady Bugs that eat Aphids.

Here's some good news.  This site says that Neem Oil does not kill bees or other beneficial insects.  The insect must eat the plant in order to die.  Ladybugs and bees are left unharmed.
I have heard of people adding neem flour to thier soil and some even use neem flour as their media to ward off pests.   I have been wondering if this would destroy the beneficial organisms in the soil.  I asked the worm farm where  I buy my compost and castings to run a test, but they never did.  So I asked for a microscope for my birthday.  I should have an answer near the end of July.

According to Insecticidal soap does not kill bees or hard bodied insects and only kills soft bodied insects when it is wet.  Unfortunatly it does kill some beneficial insects such as syrphid fly larvae and beneficial predatory mites.

Molasses offers good protection, and it will not hurt the beneficial insects.  It can also be mixed with Essential Micro Nutrient (EM) to create a health boosting shield against the insects we which to keep away.
Chamomile tea, horsetail tea, copper and sulfur products are often used for fungicides.  I have not looked to see if they are friendly towards the beneficial insects.   Milk garlic and baking soda are also used and I would imagine that they are pretty safe.

There are different strains of B.t. (Bacillus thuringiensis), each with specific toxicity to particular types of insects:
B.t. aizawai (B.t.a.) is used against wax moth larvae in honeycombs;
B.t. israelensis (B.t.i.) is effective against mosquitoes, blackflies, fungus gnats and some midges;
Most of the BT   formulations contain Bacillus thuringiensis var. kurstaki. .
B.t. kurstaki (B.t.k.) controls various types of lepidopterous insects, including the gypsy moth and cabbage looper.
A new strain, B.t. san diego, has been found to be effective against certain beetle species, Colorado potato beetle, and the boll weevil.
In order to be effective, B.t. must be eaten by insects in the immature, feeding stage of development referred to as larvae. It is ineffective against adult insects. Monitoring the target insect population before application insures that insects are in the vulnerable larval stage (9). More than 150 insects, mostly lepidopterous larvae, are known to be susceptible in some way to B.t. (5).   - Extension Toxicology Network

The package label will say for which insects the product is effective.  There are about 150 species of pest moths and butterflies that are susceptible to Bt in their larval stage, including tomato hornworm, corn earworm, cabbage looper, imported cabbageworm, and the diamondback moth.

Target pests of Bacillus thuringiensis var. kurstaki

The following pests are susceptible to B.t. var. kurstaki, the most common commercially available species. Be sure to read all labels before treatment to make sure your target pest is included.
Cabbage looper
Diamondback moth
Fall cankerworm
Fall webworm
Gypsy moth
Imported cabbageworm
Indianmeal moth
Mimosa webworm
Sod webworm
Spring cankerworm
Tent caterpillars
Tomato/tobacco hornworm

It's important to learn how to identify the bugs in your garden so you know whether they are beneficial or not.   This is one of my favorite sites for insect identification.

This PDF  offers many ways to protect your garden without pesticides and is a good place to start.
Insect Frass is also a great way to protect your garden and provide extra nutrients as well.  Here is more information about Frass.
or read the post I made about Frass a few days ago

Boric acid which is nontoxic to birds, fish, aquatic invertebrates, and relatively nontoxic to beneficial insects is effective in killing fire ants, spiders, cockroaches, fleas, termites, beetles, silverfish, and cockroach colonies.

Spinosad has high efficacy, a broad insect pest spectrum, low mammalian toxicity, and a good environmental profile. This is a unique feature of an insecticide, compared to others that are currently used for the protection of grain products.[5] Spinosad is considered a natural product and approved for use in organic agriculture by numerous national and international certifications.[8]    - Wikipedia
Spinosad is a novel insect control agent derived by fermentation of the Actinomycete bacterium, Saccharopolyspora spinosa. Spinosad controls many caterpillar pests in vines, pome fruit and vegetables (including tomatoes and peppers), thrips in tomatoes, peppers and ornamental cultivation and dipterous leafminers in vegetables and ornamentals. Application rates vary between 25 to 100 g of active substance per hectare (g as/ha) and 4.8 to 36 g of active substance per hectolitre (g as/hL) depending on the crop and target pest. It is important that plant protection products are authorized for use only in ways that do not pose an unacceptable risk of harm to honeybees. For this purpose testing was performed to enable the safety of spinosad to be evaluated. The effects of spinosad to honeybees have been extensively researched. Testing has been performed under a variety of conditions in a range of countries globally. Studies to determine the acute toxicity of spinosad under laboratory conditions were conducted to generate LD50 or LC50 values for oral and contact routes of administration. These demonstrated that spinosad was highly toxic to worker honeybees under worst case laboratory conditions and that the oral route of exposure provided the greater risk. Residue tests conducted under laboratory, semi-field and field conditions on worker honeybees foraging on treated foliage indicated that dry product residues were harmless. Therefore the effects seen in the laboratory acute toxicity tests did not translate to a more realistic exposure scenario indicating that safe use patterns for the product can be developed. Semi-field cage studies have also demonstrated that spinosad was safe to bees when applied to flowering crops during periods of bee activity. The majority of studies conducted have indicated that spinosad does not adversely affect honeybee behaviour, brood or queen. It can be concluded that spinosad when used according to the approved product label recommendations, would be safe to foraging worker bees, queen and brood. Additional levels of safety could be achieved by avoiding situations where bees would forage primarily on aphid honey dew. - Dow AgroSciences

This product uses an Octopamine Blocker which is a lot like adrenaline to an insect.  It over excites their nervous system and kills them.  I became interested in this product when I had a severe outbreak of ants in my aquaponic green house.  While it is safe for mammals and fish I would worry about using it around crustaceans.   It is broad spectrum so you must also be careful not to kill beneficial insects like ladybugs and bees.

I used this product in my house and green house.  I did find one dead cockroach in the garage where I dumped a very large amount of Essentria_IC3 mixed at the lowest recommended strength of 1/2 oz per gallon of water.   This same ratio did nothing to the ants and aphids I wanted to kill.

I then mixed 6 oz per gallon (the maximum recommended dosage) and sprayed heavily in the green house, and on a heavy infestation of aphids on my cabbage. Once again the product failed to kill anything including the aphids which received a heavy drenching.  I waited 5 days and then mixed the Essentria_IC3 at  96 oz per gallon.  Sixteen times the recommended strength.   The good news is it did not harm the fish and it did kill both the aphids and the ants.  The bad news is it destroyed many of my plants.  It may be a better herbicide than it is a pesticide.

I would not recommend Essentria_IC3.  It's was ineffective in my green house and garden.  The smell is horrid, and required that I air my house out for two days when mixed at the lowest ratio.
Diatomaceous earth (DE) is non toxic and far better than many poisons.  But it kills all bugs including bees, and other beneficial insects so it's not always the best choice.
It's only effective until it becomes wet.  This is a really good thing because it allows you to use DE for a specific period of time.  Bees tend to come around in the morning and afternoon.  Dusting DE in the evening will avoid getting it on the bees.  But you still risk killing many other beneficial insects.
DE kills due to its sharp edges, and will only kill the insects that come in contact with it so it will not kill the other bees in a hive.  It's safe for humans and other mammals, but it would not be my first choice because it's an indiscriminate killer.
For more information

Make Your Own Bug Sprays
 Nicotine -  Extremely toxic to insects. Nicotine tea is short lived, retaining its toxicity for only a few hours after spraying. It is relatively nonhazardous to bees and lady beetles because of its short persistence, but timing is required.
Pyrethrum - The dried, powdered flowers of the pyrethrum daisy, Tanacetum cinerarifolium, were used as early as 1880 to control mosquitoes.
Capsaicin - Black pepper, chili pepper, dill, ginger, paprika, and red pepper all contain capsaicin, a compound shown to repel insects.
Herbal Sprays - Extracts of Hyssop, Rosemary, Sage, Thyme,  White Clover, Wormwood,  Nasturtiums, Catnip, Chives, Feverfew, Marigolds, or Rue can be used.
Garlic Oil - Combine with mineral oil and pure soap
Tomato Leaf - Soak chopped leaves. Contains toxic compounds called alkaloids and attracts natural pest enemies.Alcohol Sprays - Alcohol sprays work on aphids, mealy bugs, scale insects, thrips and whiteflies
 For more information about these homemade sprays - Comfy Country Creations

More Links:
Sierra Club - Imidacloprid Fact Sheet
The Basics of Organic Gardening in 15 minutes
Key to Major Beneficials and Pests

Update 5/26/13 Some of my cucumbers leaves are showing damage.  I could not find the pest, but I suspect a worm, so I sprayed BT kurstaki.

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